This operator's manual contains a description of the engine, its
specifications, and detailed information on how to operate and maintain
Such maintenance procedures
it. with periodic inspections are also included. This manual is intended foruse by owners, pilots and maintenance Avco Lycoming powered aircraft. are contained nel should refer to these for such procedures.
Neglecting to follow
periodic
and power loss. Also, if power and speed limitations specified in thismanual are exceeded, for any reason, damage to the engine and personalinjury can happen.
ty.
SERVICE BULLETINS,
Although the information contained in this manual is up-to-date attime of publication, users are through Avco ters which factory by subscription. L114 for subscription information.
in Avco Lycoming overhaul
SAFETY WARNING
the operating instructions
maintenance procedures
Consult your local FAA approved
Lycoming Service Bulletins,
are available from all Avco Lycoming
Consult the latest edition
that may be required in conjunction
Modifications and repair
can result in poor engine performance
INSTRUCTIONS
urged to keep abreast of later
AND
personnel responsible
manuals; maintenance person-
and to carry out
maintenance facili-
AND LETTERS
Instructions and Service Let-
distributors or from the
of Service Letter No.
for care of
procedures
information
SPECIAL NOTE
illustrations, pictures and drawings
The
typical of the subject matter they portray; in no instance are they to be
interpreted as examples of any specific engine, equipment or part
thereof.
shown in this publication
are
TEXTRON LYCOMING OPERATOR'S MANUAL
IMPORTANT
Proper service operation by operations. Some of specially and as recommended.
It is important tain various Warnings order to minimize the risk of vice methods that may damage the engine or render it unsafe.
It is also important to are evaluate or advise
vice might be done be involved. satisfy themselves ty will be
of all aircraft engines. The service
Textron Lycoming
designed for the task. These
not all inclusive. Textron
and repair is essential
are effective
these service operations require
to note that most Textron Lycoming
and Cautions which
understand that these Warnings
the service trade of all conceivable
or of the possible hazardous
Acordingly,
jeopardized
anyone who
thoroughly
by the service
SAFETY
personal injury or the use of
Lycoming could not possibly
that neither
NOTICE
to increase the safe, reliable
procedures recommended
methods
special tools must be used
uses a service
procedure
for performing
the use of tools
publications con-
must be carefully read in
improper ser-
and Cautions
ways in which ser-
consequences that may
procedure must
their safety
nor aircraft safe-
they select.
service
when
know,
first
NEWAND REMANUFACTURED
(LIMITED)
RECIPROCATING AIRCRAFT ENGINE
WHAT TEXTRON
Textron Lycoming warrants each new and remanufactued reciprocating engine sold by it to be free from defects inmaterial and acceptance testing The date of first operationmust not exceed two (2) years from the date ofshipment from TextronLycoming.
change basis, of the engine or any in material or workmanship. Lycomig will also bear the cost for labor in connection with the repair or replacement as provided in TextronLycoming's
the period from the date of first operation, whichever occurs first, Textron Lycoming will reimburse you for a pro rata portion of thecharge for the repair or replacement (at its choice) with Textron Lycoming parts,ofparts required tobe repairedorre-placed, or a replacement during the proration period extends to major parts of the engine, which are limited to crankcase, crankshaft, camshaft,cylinders, connecting rods, pistons, sump, accessory housing and gears. The proration policy does not extend to labor orto accessories, including but not limited to magnetos, caburetors or fuel injectors, fuel pumps, sarers, alternators andturbochargers and their controllers.
Lycoming distributor within 30 days of the appearance of the defect in material or workmanship.
the part of Textron Lycoming set forth above are your exclusive remedy and the exclusive liability of Textron Lycoming.This warranty allocates the risk of product failure between you and Textron Lycoming, as permitted by applicable law.
been subject to accident or used, adjusted, altered, manual, or if non-genuine Textron Lycoming parts are installed in or on the engine and are determined tobeapossiblecause of the incident for which the warranty application is filed.
such alterations in engines or parts previously sold.
workmanship appearing within one (1) year from
Textron Lycoming's
In addition, if Textron Lycoming determines
until the expiration of Textron Lycoming's recommended
Any engine or
The
engine must have
Textron Lycoming's warranty does
Textron Lycoming
Textron Lycoming may change the
obligation under this warranty shall be limited
part of the engine, when Textron Lycoming has determined
Such repair or replacement will be made
then current Removal and
part so repaired or
reserves the right
Installation Labor Allowance Guidebook.
engine, if it determines that engine replacement
replaced will be
received normal
not cover normal maintenance expenses or consumable
construction of engines at any time without incurring
LYCOMING PROMISES
the date of first operation, excluding necessary aircraft
to its choice of repair or replacement, on anex-
by Textron Lycoming at no charge to you. Textron
that the engine proves to be defective in material
entitled to warranty
OBLIGATIONS
YOUR
use and service.
to deny any warranty claim
handled, maintained or stored other than as directed
Time Between Overhaul (TBO), or
is required. Textron Lycoming's obligation
for the remainder
You must apply
for warranty
if it reasonably determines
YOU
that the engine is defective
or workmanship during
two (2) years
of the original
with an authorized
any obligation to incorporate
waranty period.
Textron
items. The obligations on
that the engine or part
in your operator's
has
THIS LIMITED TATIONS, LIMITED TO ANY WARRANTY OF MERCHANTABILITY AND ANY IMPLIED WARRANTY TRADE USAGE. THIS CLAIM, WHETHER IN CONTRACT OR IN TORT, INCLUDING ANY RIGHT IN STRICT LIABILITY INTORT TEXTRON LYCOMING'S LIABILITY ON CABLE TO THE ENGINE
WARRANTY IS EXCLUSIVE AND IN LIEU
EXPRESS OR IMPLIED OR STATUTORY,
WARRANTY IS ALSO IN LIEU OF ANY OTHER
OR ANY RIGHT ARISING FROM NEGLIGENCE
ARISING FROM ANY COURSE OF PERFORMANCE
OR PART WHICH GIVES RISE
WHETHER WRITTEN OR ORAL, INCLUDING
SUCH CLAIM SHALL NNO CASE EXCEED
OF ALL. OTHER WARRANTIES AND REPRESEN-
OR FITNESS FOR ANY PARTICULAR
OBLIGATION, LIABILITY, RIGHT OR
ON THE PART OF TEXTRON LYCOMING,
TO THE CLAIM.
BUT NOT
PURPOSE,
OR DEALING OR
THE PRICE ALLO-
AND
LIMITATION
IN NO EVENT, WHETHER LIGENCE, SHALL TEXTRON LYCOMING DAMAGES, INCLUDING BUTNOT LIMITED TOLOSSOF PROFITSOR REVENUES, LOSS OF USE OF THEENGINE OR COST OF A
No agreement varying
Lycoming unless in writing signed by a duly authorized representative of Textron Lycoming.
Effective October
AS A RESULT OF A BREACH OF WARRANTY,
REPLACEMENT.
this warranty or Textron Lycoming's obligations
1, 1995 Revision
"J'
OF LIABILITY
BE LIABLE FOR SPECIAL OR CONSEQUENTIAL
CONTRACT OR ALLEGED NEG-
under it will be binding upon Textron
Textron
Williamsport, Pennsylvania
OR ANY OTHER
Lycoming
WARRANTY
REPLACEMENT
Textron Lycoming
inmaterial and
must not exceed
tion.
Textron
basis, of te
change
workmanship. ment as provided
part so repaired
Any
The engine warranty workmanship.
Textron
part of Textron
the
This warranty
Textron
been subject to manual, or if non-genuine
cause of the
Textron
such alterations
THIS LIMITED TATIONS,
LIMITED AND ANY
USAGE.
TRADE CLAIM,
OR ANY
TORT TEXTRON CABLE TO THE
warrants each
workmanship appearing
two (2) years from
Lycoming's obligation
replacement part,
Lycoming will
Textron
in Textron Lycoming's
in which
with an authorized
Lycoming's
Lycoming
the risk of
allocates
Lycoming reserves
accident or used,
incident for
may change the
Lycoming
engines or
in
WARRANTY
OR IMPLIED
EXPRESS
ANY WARRANTY
TO
WARRANTY
IMPLIED
THIS WARRANTY
WHETHER
IN CONTRACT
RIGHT ARISING
LYCOMING'S
ENGINE OR PART
PART -RECIPROCATING
(LIMITED)
WHAT TEXTRON
new reciprocating aircraft
under this
when TextronLycoming
also reimburse you
will be warranted
or replaced
the replacement
Textron Lycoming
does not cover
warranty
which the warranty
above are your
set forth
product failure
the right
adjusted, altered,
Textron Lycoming parts are installed
construction of
pars previously
IS EXCLUSIVE
OR STATUTORY,
OF MERCHANTABILITY
ARISING IS ALSO IN
FROM
LIABILITY
WHICH GIVES
LYCOMING
one (I) year from
within
the date of shipment
warranty shall
then current Removal
for the remainder
OBLIGATIONS
YOUR
part is installed
distributor
normal maintenance
exclusive
between
any warranty
to deny
handled, minained
application
engines at any time
sold.
AND IN
FROM
LIEU OF ANY
OR IN TORT,
NEGLIGENCE
CLAIM
ON SUCH
AIRCRAFT
PROMISES
engine replacement pat
from Textron
be limited to its
has
for the costs
and Installation
have received
must
within 30 days
remedy and
you and Textron
claim if it reasonably
in or on the engine and are determined to be a possible
Cooling System ........................................1-3
Lubricating System .....................................1-3
Induction System .......................................1-3
Ignition System
Table of M odels ........................................1-4
M echanism .............................
........................................
OPERATOR'S
MANUAL
Page
1-11-21-2
1-3
LYCOMING
OPERATOR'S
MANUAL
0-235 AND
The engines air-cooled
In referring are described tional airframes.
the
accessory bottom located made with cylinder The front
number the
crankshaft,
Cylinders
with the The ed combustion nickel ground
0-290 SERIES
Lycoming
are four cylinder,
models.
to
in their drive
and
the
is the top.
the observer
on the
cylinder
3. The
observer
heads
molybdenum
viewed
-The
two
are made
and
honed to
direction
facing
major
0-235 series,
the location
relationship
Thus
the power
section
opposite
References
left bank
on
the right
of rotation
the
from the
cylinders
parts,
from
chamber.
steel
a specified
SECTION 1
DESCRIPTION
direct drive,
of the various
to
take-off
the rear.
side of
the engine
to the left
facing
the rear
is
number
drive
are
head
an aluminum
The
forgings
2 and the
bank
for
pad. The
accessory
of conventional
and
barrel,
barrels,
with
finish.
0-290-D
the engine
The
is number
which
series
and 0-290-D2
horizontally opposed,
engine
components,the
as installed end is considered sump section
where
and right
of the
accessory
direction
end
screwed
alloy casting
deep integral
engine. Thus
rear
1 and
drives
of the
engine
air-cooled
are
machined
the
side of cylinder
the rear of rotation
and
with
SECTION
series
wet sump,
in conven-
the front and
is
considered
shroud
tubes
the engine
the
is number
cylinder
is determined
is clockwise.
shrunk
a fully
cooling
of
construction
together.
machin-
from
chrome
fins, are
1
parts
theareare
front
4.is
by
the
The
valve are cast which the
intake
ed
recesses
Valve Operating
on the crankshaft tuates on full steel
seats.
rocker
integrally
completely
valves,
in the
top side.
and operates
the valves
floating,
shaft bearing
with the
surround
Valve
guides and
head.
Mechanism
The
camshaft
in aluminum
by means
steel
shafts.
supports head. The the
area of
-The valve is
of tappets.
The
valve springs
valves
the exhaust
valve
seats
operating
located
bearings.
The valve
and
the rocker
are
cooled by
valve
are shrunk
mechanism
parallel
The camshaft
rockers
bear against
box
means
and
into
to and
are supported
housing
of fins
portions
machin-
is located
above
in
turn ac-
hardened
of
the
1-1
LYCOMING
OPERATOR'S
MANUAL
SECTION
Hydraulic are employed employed
latter the valve rocker.
Crankshaft -Made from
bearing crankshaft must hydro
Crankcase
alloy castings together by bolts
joined
for use
Oil Sump -
the intake
passes through
the riser.
Connecting
forgings. They and the crankshaft each cap.
1
tappets which
on the
on the 0-235
models is
surfaces are
control or variable
without the
of precision
split type bronze
maintained by
be removed
-Crankcase divided at
and nuts.
use of a gasket,
Incorporates an
riser and
the riser,
Rods -Made in the
have replaceable
ends are retained by means of
type main
intake pipe connections.
bushings in
0-235 AND 0-290
NOTE
automatically keep 0-290-D2 series and 0-290D series.
means of an adjusting
a chrome nickel molybdenum
nitride hardened.
on those models
pitch propeller.
assembly consists
the center line
The mating surfaces
and main bearing
bearing
oil suction screen,
is vaporized
form of "H" sections from alloy bearing
the piston ends.
the valve clearance
engines while
Proper valve
The expansion
employing a
of two reinforced
of the engine
inserts.
carburetor
The
by the heated
inserts in the
two bolts and nuts through
SERIES
solid tappets
clearance on
screw
located in
steel forging. All
plug two position
aluminum
and fastened
of the crankcase
bores are
fuel-air mixture,
oil that surrounds
The bearing caps
machined
mounting pad,
crankshaft ends
at zero
arethe
in the
are
as it
steel
on
Piston
-Machined
an oil
regulating ring series employs of the
full floating from touching
Accessory Housing -
the rear of housing for
Gears -Are of to insure
an oil scraper
type with
the cylinder
the crankcase and the top
the oil pump
the conventional
long life
and satisfactory
from an aluminum
are employed
ring below the
a plug
wall.
Made from an aluminum casting
and the various
alloy. Two
on all pistons.
located at
type and precision
operating
piston pin. The
each end to
rear of the oil sump. It forms
accessory
qualities.
compression
In addition, the
piston pin is
prevent
and is fastened to
drives.
machined,
rings and
0-235
the pin
a
hardened
LYCOMING OPERATOR'S MANUAL
0-235 AND 0-290 SERIES SECTION 1
Cooling
actuated by the forward up exhausted through gills or augmentor tubes usually located at the rearof the cowling.
Lubrication System -The full actuated by an impeller type oil pump contained within the accessory
housing.
Induction System -These engines are equipped with either of twoMarvel-Schebler carburetors, MA-3A or MA-3SPA. See Table 1 formodel and are equipped with ticularly tained from sump and is submerged in oil, insuring a more uniform vaporization offuel and aiding in cooling the mixture is distributed to
Cold W eather Ground Running and Checks Before Take-Off Operation in Flight
Use of Carburetor Heat Control ..........................3-6
Engine Operating Shut-Down Procedure
Performance Curves ............................
Flight Chart ....................
Starting ..................................
Warm-Up ...........................
.....................................
Conditions ..................................
................................
INSTRUCTIONS
.................................
.................
Page
3-33-33-33-4
3-8
3-8
3-10A
..3-11
LYCOMING
0-235 AND 0-290 SERIES SECTION 3
OPERATOR'S
SECTION 3
MANUAL
OPERATING
1. GENERAL. tribute to long life, economy and satisfactory operation of the engine.
YOUR ATTENTION IS DIRECTED IN PARTICULAR TO THE
WARRANTIES THAT APPEAR IN THE FRONT OF THISMANUAL REGARDING SPECIFIED ALTERATIONS. PERHAPS NO OTHER ITEM OF ENGINEOPERATION AND MAINTENANCE CONTRIBUTES QUITE SOMUCH TO SATISFACTORY THE CONSTANT USE CORRECT ENGINE TIMING,
ALL TIMES WITHIN THE SPEED AND POWER RANGE
SPECIFIED FOR THE ENGINE. DO NOT FORGET THAT VIOLA-TION OF TIONS FOR YOUR
RANTY BUT WILL SHORTEN THE LIFE OF YOUR ENGINEAFTER ITS WARRANTY PERIOD HAS PASSED.
New engines therefore no further break-in is necessary insofar as operation is concern-ed; however, new or newly overhauled engines should be operated usingonly the lubricating oils recommended in the latest edition of Service In-struction
Close adherence to these
FUELS AND
OF CORRECT GRADES OF
THE OPERATION AND MAINTENANCE
ENGINE WILL NOT ONLY
have been carefully run-in
No. 1014.
INSTRUCTIONS
instructions will greatly con-
NOTE
ENGINE SPEED, THE
LUBRICANTS, REPAIRS
PERFORMANCE
AND FLYING THE AIRPLANE
NOTE
AND LONGLIFE AS
FUEL AND OIL
SPECIFICA-
VOID YOUR WAR-
by Lycoming and
USE OF
AND
AT
Cruising should be done at 65% to 75% power until a total of 50 hours has
accumulated or oil consumption seating of the rings and is applicable to new engines, and engines in ser-
vice following cylinder replacement or top overhaul at one of more
cylinders.
The minimum fuel octane rating is listed in the Flight Chart, Part 8 ofthis section. Under no circumstances should fuel of a lower octane ratingor automotive (regardless of octane rating) be used.
has stabilized. This is to
insure proper
3-1
LYCOMING OPERATOR'S
SECTION 3 0-235 AND 0-290 SERIES
2. PRESTARTING ITEMS OF MAINTENANCE. Before starting theaircraft engine for the first maintenance inspection Section 4 under Daily before the
3. STARTING PROCEDURE.
a. Perform pre-flight inspection.b. Head airplane into wind.c. Lock wheels by either wheel brakes or chocks.d. Set carburetor heat control in "cold" position.
engine is started.
flight of the day, there are several that should be performed. Pre-Flight Inspection. They
MANUAL
items of
These are described in
must be observed
e. Set propeller governor f. Turn fuel valve to "on" position.g. Set throttle at 1/4 travel.h. Move mixture control to "Full Rich".i. Turn boost pump on.
j. Pump throttle to full open
for a cold engine. If engine is equipped with a priming system, cold
engine may k. Set magneto selector switch. Consult airframe manufacturer's
handbook for correct position.
1. Engage starter.m. When engine fires, place magneto switch in "Both" position.n. Check oil pressure gage. If oil pressure is not indicated within thirty
seconds, stop engine and determine trouble.
3-2
be primed with 1 to 3
(if applicable) in "Full RPM"
and back to idle position for
strokes of the priming pump.
position.
2 to 3 strokes
LYCOMING
OPERATOR'S
MANUAL
0-235 AND
4. COLD
0-290
SERIES
WEATHER STARTING.
be necessary to preheat
5. GROUND
pressure maintain operating recommended
Any ground check
three minutes, the maximum
RUNNING AND
cooled and depend
proper
cooling.
these engines
that the
that requires
or less if
as stated in this
a. Head the aircraft b. If
a controllable
the ground only
c.
Leave the mixture
pitch propeller
with the propeller in minimum
d. Avoid prolonged fouled plugs. warm engine
e. Use of the solute minimum.
Limit ground
for take-off.
carburetor air
On some the air filter and dirt engine
with the resultant heat should be ing
properly.
used on the ground
During
the engine and oil
extreme cold
before starting.
WARM-UP.
on the forward
Particular
on the ground.
following procedures
care
is necessary,
To prevent
movement
be
NOTE
the indicated cylinder
into the
full throttle manual
wind.
operation must
head temperature
is installed, operated
control in "Full Rich".
idling at
low RPM as
running
to minimum
this practice may
heat on the ground
installations
the air does
and foreign substances can
cylinder
and piston ring
only to
make certain it
SECTION
weather, it
Subject engines
of the aircraft
therefore,
overheating,
observed.
be limited to
the engine
blade angle setting.
time necessary
must be held
not pass through
be taken into the
wear. Carburetor
is function-
3
may
are air
to
when
it is
exceeds
on
result in
to
to an ab-
air
6. CHECKS BEFORE
a. Warm
b. Check both
c. Set carburetor
Loss fixed pitch
will
up as directed
oil temperature
air heat
of manifold pressure
or controllable
result if the
control is working
position after check.
TAKE-OFF.
above.
and oil pressure.
control for "full
or RPM pitch propeller
(or both), depending
heat" to check
is installed
properly.
Return control
operation.
on whether
on the aircraft,
to "cold"
3-3
a
LYCOMING
OPERATOR'S
MANUAL
SECTION 3
d. A proper magneto check the ignition system, output, propeller pitch and that the engine runs variables listed above. Make following
(1) Controllable Pitch
angle, set the engine to produce manifold position. At these settings work harder Under these conditions, ignition Magneto checks distribution quality.
Aircraft
with manifold
operating
(2) Switch from both both until engine note drop-off, then and should not exceed 50 smooth drop-off past mixture.
(3) Do not
seconds
fouling.
procedures:
pressure gage. Mixture
that are equipped with fixd pitch
pressure
at approximately 1800 RPM
operate on a single magneto
is usually sufficient to check
affect magneto drop-off. They
smoothly because drop-off
because
of the greater
at low power settings will
gage, may check
magnetos to one and note
regains speed and switch
return to both. Drop-off should
normal is usually a sign of a
0-235 AND 0-290
is important. Additional factors,
mixture strength. The important
the magneto check in accordance
Propeller -With propeller
50 to 65% power as indicated
control should be in the
the ignition system and spark
pressure within
problems, if they exist,
NOTE
propellers, or not equipped
magneto drop-off
(2000 RPM maximum).
RPM difference between
for too long a period, 2 to
drop-off and will minimize
is affected by the
in minimum pitch
only indicate fuel-air
drop-off, return to
to the other magneto and
too lean or too rich
SERIES
other then
are, load-power
thing is
with the
by the
full rich
plugs must
the cylinders.
will occur.
with engine
not exceed 175
magnetos. A
3
plug
7. OPERATION IN FLIGHT.A. See airframe manufacturer's instructions for correct manifold
pressure for power settings.
B.
Fuel Mixture Leaning Procedure
flight is
take-off and climb manual provide proper engines, they eliminating excessive replacement. It is therefore
responsible for many engine
power settings. The procedures
fuel-air mixture when leaning
have proven to be both economical
fuel consumption and reducing
recommended that operators
-Improper fuel-air mixture problems, particularly during
described in this
Avco Lycoming
and practical by
damaged parts
of all Avco
during
LYCOMING OPERATOR'S MANUAL
AND 0-290 SERIES
0-235
Lycoming tion any time
Never exceed
continuous operation
For tained
On direct drive control in "Full Rich" tinuous, from high elevation airport
result from over-richness.
may enough to obtain struments for temperature rise. mixture is most likely
Always enrich
C. LEANING TO
(1) Above 75% power -Never lean beyond 150°F. on rich side of peak
EGT unless aircraft operator's manual shows otherwise. Monitorcylinder head temperature.
(2)
D. LEANING WITH MANUAL MIXTURE CONTROL. (At 75%
power or
(1) Slowly move mixture control from "Full Rich" position towardlean position.
aircraft powerplants
the fuel-air
LEANING
the maximum red line cylinder
below 435°F.
climb and cruise
75% power and below
less without
(224°C.).
engines with manual mixture
position for rated take-off rated
smooth operation -not
to be encountered at altitude
mixture before increasing
EXHAUST GAS TEMPERATURE
flowmeter
utilize the
mixture is
PRECAUTIONS
cylinder
powers above
or during climb, roughness or
head temperatures
such a case adjust
In
Rough operation due to over-rich
-Operate at peak
or EGT
instructions
adjusted during
head temperature limit.
control maintain mixture
75%. However,
mixture control
for economy. Observe in-
power.
EGT.
gage.)
SECTION
in this publica-
flight.
should be
maxmimum con-
during take-off
loss of power
fuel-air
above 5,000 feet.
GAGE.
3
main-
only
(2) Continue leaning until engine roughness is noted.(3) Enrich until
E. ALTERNATE
propellers.)
(1) Slowly move watching tachometer.
(2) At this point enrich until is obtained at this point.
engine runs smoothly
METHOD. (In calm
mixture control toward lean
Continue leaning until
RPM just peaks. Correct
and power is regained.
air and engines with fixed pitch
position while closely
RPM decreases.
fuel-air ratio
3-5
LYCOMING OPERATOR'S MANUAL
SECTION 3 0-235 AND 0-290 SERIES
NOTE
Leaning may be done at any altitude that the engine will accept leaning:The greater the altitude the more important leaning becomes. Properleaning is important because more engine power and increased air speedare obtained along with decreased fuel consumption, longer spark pluglife, less lead fouling, temperatures. Engine damage from leaning the mixture does not occurat the specified cruise power power plant, but is the result of improper leaning atpower settings aboverecommended
Use of Carburetor Heat Control
F.
conditions, it is possible for ice to form in the induction system even insummer weather. This is due to the high air velocity through the car-buretor venturi and the absorption of heat from this air byevaporization of the fuel. The temperature in the mixture chambermay drop 20°F. to 70°F. below
this air contains a large cause begin in the vicinity of the extent that a drop in manifold power output results. This loss of poweris reflected by a drop in manifold with constant
RPM in detected, this condition will continue to such an extent that thereduced power will cause complete engine stoppage.
To avoid this condition, all installations are equipped with a systemfor preheating the incoming air supply to the carburetor. In this way,sufficient heat is added to replace the heat loss to vaporization of fuel,and the mixing point of water. This air preheater is essentially a tube or jacketthrough which the exhaust pipe from one or more cylinders is passed,and the air flowing over these surfaces is raised to the requiredtemperature before entering the carburetor. Consistently hightemperatures are to decided variation of the mixture. High charge temperatures also favordetonation and preignition, both of which are to be avoided if normalservice life the proper method
cruise.
precipitation in the form
speed propellers and a drop
installations equipped with
chamber's temperature cannot
is to be expected from the
and more normal oil
for the model engine in a basically
-Under certain moist atmospheric
the temperature of the incoming
amount of moisture, the
of ice. These ice formations generally
butterfly and will often build
pressure in installations
fixed pitch propellers. If not
be avoided because of a loss
engine. The following outline
of utilizing the carburetor
and cylinder head
healthy
air. If
cooling process will
up to such an
equipped
in manifold pressure and
drop to the freezing
of power and a
is
heat control.
0-235
AND 0-290 SERIES
LYCOMING
OPERATOR'S
MANUAL
SECTION
3
(1) Take-Off- Take-off cold position. The possibility remote.
(2) Flight
the cold foggy or hazy lookout
Operation -The carburetor
position during normal flight
days, regardless of outside temperature,
for loss of power. This countable loss in manifold whether aircraft. When and
a constant speed or fixed pitch
this situation arises, apply
open the throttle to limiting in a slight additional this drop will system.
be regained
When the ice has been the carburetor heat In those aircraft partial
heat may be used
freezing
Caution must
that do not have form that raised crystals ice due carburetor. aircraft that
point (32°F.).
would ordinarily
in temperature
are melted
to the temperature
It is advisable,
are not equipped with a carburetor
be exercised when operating
equipped
a carburetor
into liquid form.
should be made with
carburetor heat in full
of icing at wide throttle
air heat control should
operations. On damp, cloudy,
loss of power will be shown
pressure or RPM or
both, depending on
propeller is installed on the
full carburetor air heat
manifold pressure. This will
drop in manifold pressure which
as the ice is melted
out of the
melted from the induction
control should be returned to
to keep the
WARNING
air temperature
pass through
by use
drop as it
therefore,
with a carburetor
mixture temperature
the induction
of partial heat
This moisture
passes through
to use
air temperature
with partial heat on aircraft
gage. Moisture
to the point
can form carburetor
either full
air temperature gage.
opening is very
be left in
keep a sharp
by unac-
result
is normal and
induction
system,
the cold position.
gage,
above
the
in crystal
system, can
where the
the venturi of heat or
no heat in
be
the
(3)
Landing Approach
-In making
buretor air heat should However,
Heat" should under heat should See aircraft
if icing
conditions are
be applied.
these conditions,
be returned to "Full Cold"
flight manual for specific
usually be in the "Full
an approach
known or suspected,
In the case
as for
that full power
an aborted
landing, the carburetor
prior to power application.
instructions.
for a landing,
Cold" position.
then
need be applied
car-
"Full
3-7
LYCOMING
OPERATOR'S
MANUAL
SECTION 3 0-235 AND 0-290 SERIES
8. ENGINE FLIGHT CHART.
Fuel and OilModel
O-235-C, -E, -H2C
O-235-F, -G, -J, -K, -L, -M,
O-290-D, -D2 ....
* Refer to the latest edition of Service Instruction No. 1070.
Aviation grade are
approved for continuous
..........
100LL fuels in which the lead
.....................
-N, -P .... .100/100LL
NOTE
content is limited to 2 c.c. per gallon
use in the above listed engines.
*Aviation Grade
.80/87 octane minimum
octane minimum
...80/87 octane minimum
Fuel
**Recommended Grade Oil
Average
Ambient Air
All Temperatures Above 80°F. Above 60°F. (15.5°C.) 30 (-1.11°C.) to 90°F. (32.2°C.) SAE 40 SAE 40
0°(-17.8°C.) to 70°F.
Below 10°F. (-12.2 C.) ** Refer to the latest edition of Service Instruction No. 1014.
b. Be sure magneto ground wires are connected.c. Check oil level.d. See that e. Check
at 50 hour inspection. Repair any major leaks before aircraft is flown.f. Open the fuel drain to remove
ment.g. Make sure all shields and
missing or aircraft is flown.
h. Check controls for general condition, travel and freedom of opera-tion.
i. Induction system air filter should be inspected and serviced in ac-cordance with the airframe manufacturer's recommendations.
2. 25-HOUR
time, a 50 hour inspection including draining and renewing lubricating oil.
3. 50-HOUR
flight inspection, every 50 hours of operation.
4
the "Off"
all switches
fuel tanks are
fuel and oil line connections,
damaged, repair or replacement
INSPECTION. After the
new, remanufactured or newly
INSPECTION. In addition
the following maintenance checks
are in
full.
cowling are in place and secure.
any accumulation of water
overhauled engines should
0-236 AND 0-290
position.
note minor indications for
should be made before the
first twenty-five hours operating
to the items listed for daily
should be made after
SERIES
repair
and sedi-
If any are
undergo
pre-
Ignition System -Remove
a.
Replace if necessary.
Examine spark plug leads of cable and ceramics for corrosion and
deposits. This condition
cleaning of the spark plug
proper condition is found, clean the cable ends, spark plug walls and ceramicswith a dry, clean ketone. All parts should be clean and dry before reassembly.
Check ignition harness for security of mounting clamps and be sure
connections are tight at spark plug and magneto terminals.
4-2
cloth or a clean cloth moistened
spark plugs; test, clean and
is evidence of either leaking
walls or connector ends. Where
spark plugs, im-
with methyl-ethyl
regap.
this
LYCOMING OPERATOR'S MANUAL
0-235 AND 0-290 SERIES SECTION 4
b. Fuel and Induction System -Check primer lines for leaks andsecurity of clamps. Drain carburetor and clean carburetor fuelstrainer. Check mixture freedom of movement, security of clamps and lubricate if necessaryCheck carburetor air intake ducts for leaks, security, filter damage;
evidence of dust or other solid material in the ducts is indicative of
inadequate filter care or damaged filter. Check vent lines for evidenceof filter or oil seepage; if present, fuel pump may require replacement.
c. Lubrication System -Check oil lines for leaks, particularly at con-nections; for security of anchorage and for wear due to rubbing orvibration, for dents and cracks.
Drain and refill sump with new oil on installation not employingreplaceable external oil filter. See the latest revision to Service In-struction are listed in Section 3, Paragraph 8 of this manual.
Remove oil suction and oil pressure screens and clean thoroughly.
Note carefully for presence of metal particles that are indicative of
internal engine damage.
If engine is equipped with external oil filters, replace at this time.Before disposing of filter, check interior for traces of metal particlesthat might be evidence of internal engine damage.
No. 1014 for recommended
control and throttle
lubricating oils. Seasonal
linkage for travel,
grades
d. Exhaust
cylinders removed and machined flat before they are reassembled and tightened.
Examine exhaust manifolds for general condition.
e. Cooling System -Check cowling for damage and secure anchorage.Any damaged or missing part of the cooling system must be repairedor replaced before the aircraft resumes operation.
f. Cylinders -Check rocker box covers for evidence of oil leaks. Iffound, replace gasket and tighten screws to specified torque (50 inchpounds).
Check cylinders for evidence of excessive heat which is indicated byburned paint on the cylinder. This condition is indicative of internaldamage to the cylinder and, if found, its cause must be determined andcorrected before the aircraft resumes operation.
System -Check attaching
for evidence of leakage. If
flanges at exhaust ports
they are loose, they must
onbe
4-3
SECTION
Heavy
and
barrel cant used leakage condition and
operation.
ditions,
4.
100-HOUR
pre-flight shouldbe
a.
Electrical
cessories. Replace and
cleanliness.
b.
Magnetos
oil
in the breaker
cloth.
The accordance magneto Paragraph
c.
Engine
temperature mounting,
d
Cylinders
LYCOMING
4
discoloration
attachment
during
which
is
the
and made
faulty clamps
to
assembly
stops
neither cylinder
Any
felt
engine
lb of
Accessories
tight
harmful
If
it can
INSPECTION.
50
hour
after
every
System
shielded
-Check compartment,
located
with
the magneto
timing.
this manual.
and
pressure
connections
-Check
and appearance
area is
usually
of the barrel
after
cylinder
nor detrimental
be proven
should
be replaced.
In
inspection
-Check cables
or loose
condition
at
-Engine
visually
addition
one
hundred
all
wiring that wires
of breakers
if found,
the breaker
Timing
mounted
sensing
and
for
OPERATOR'S
0-235 AND
of seepage
due to
emission
at
has
that
the following
manufacturer's
procedure
units
terminals.
cracked
the factory,
been
in service
to the
the leakage
to
the
hours
of
connected
are damaged
and check
points.
wipe
points
is
accessories
should
or broken
MANUAL
at
the cylinder
engine
exceeds
items
maintenance
operation.
to
the engine
should
terminals
Check
dry with should
be
instructions.
described
be checked
fins.
0-290
SERIES
of thread
or
by slight
for awhile.
performance
these
listed
for daily
be
replaced.
for
security
for
excessive
a clean
lintless
lubricated
in Section
such
as pumps,
for
head
lubri-
gas
This
con-
checks
or
ac-
Check
secure
in
5,
e. Engine
security ly worn.
f Primer
for
equal
g.
Valve
Paragraph
h.
Carburetor
The
correct
4-4
Mounts
and
excessive
Nozzles
flow.
Rockers
11 for valve
-
Check
torque
-Check wear.
-
Disconnect
(0-235
and
rocker
throttle
for these
engine
0-290-D)
mounting
Replace
primer
clearance.
body
screws
any
bushings
nozzles
-
Check
attaching
is 40 to
bolts
and
that
from
engine
clearance.
screws
50 inch
pounds.
bushings
are excessive-
and
check
See Page
for
5-15,
tightness.
for
LYCOMING
0-235 AND 0-290 SERIES SECTION 4
OPERATOR'S
MANUAL
i. Lubrication
filter.
5. 400-HOUR INSPECTION.
pre-flight, 50 hour check should be made after every 400 hours of operation.
Valve
Inspection -Remove rocker
valve rockers when valves are closed. Look for evidence of abnormal
wear or broken parts and spring seat. If any indications are found, the cylinder and all of itscomponents assembly) and inspected for further damage. Replace any parts that donot conform with limits shown
System -Drain and renew
In addition to
and 100 hour inspections,
box covers and check for freedom
in the area of the valve tips, valve
should be removed (including
in the latest publication
lubrication oil. Replace
the items listed for daily
the following maintenance
keeper, springs
the piston and connecting rod
of Special Ser-
oil
vice Publication No. SSP1776.
6. NON-SCHEDULED INSPECTIONS. Occasionally, service bulletinsor service instructions are issued by Avco Lycoming Division that re-quire inspection procedures publications, usually obsolete after corrective modification has been accomplished. All suchpublications are available from Avco ,ycoming distributors, or from thefactory by tion information. Maintenance facilities should have an up-to-date file ofthese publications available at all times.
subscription. Consult Service
are limited to specified engine
that are not listed in
Letter No. L114 for subscrip-
this manual. Such
models and become
of
4-5
LYCOMING OPERATOR'S
MAINTENANCE PROCEDURES
Ignition and Electrical System
Harness and Wire Replacement .........................5-1
Timing Magnetos to Engine ............................5-1
Generator or Alternator
Fuel System
Repair of Fuel Leaks ..................................5-7
Carburetor
Fuel
Grades and Limitations Air Intake Ducts Idle Speed and Mixture
Lubrication System
Inlet Screen Assembly
and Filters .........
Output .........................
......................5-7
...........................
Adjustment .....................
MANUAL
..................5-7
Page
5-6
5-7
5-7
Oil Grades and Limitations ........................... 5-8
Removal of Cylinder Assembly .........................5-9
Assembly of Cylinder Assembly .......................5-12
Generator Drive Belt Tension ...........................5-14
Capacity ....................................
Pressure Screens .....................
5-85-8
LYCOMING
OPERATOR'S
MANUAL
0-235 AND 0-290 SERIES
SECTION 5
MAINTENANCE PROCEDURES
The procedures described in this section are provided to guide and in-struct personnel in performing required in conjunction with the periodic inspections listed in thepreceding section. No operations that will be found in the applicable Avco Lycoming OverhaulManual.
1. IGNITION AND ELECTRICAL SYSTEM.a. Ignition Harness and Wire Replacement -In the event that an ig-
nition harness ing diagram to be sure harness is correctly installed. Mark location ofclamps and locations.
b.
Timing Magnetos to Engine
magnetos model application) are
the same
Either the impulse coupling
plicable) is installed on the left side of the engine.
clips to be certain the replacement
are used on this series
attempt is made to include repair
or an individual lead is to be
the timing
for
all magnetos.
such maintenance operations
replaced, consult the wir-
is clamped at correct
-Although several combinations engines, (see Table of Models
procedures,
NOTE
or retard breaker magneto (whichever
in the following
SECTION 5
that may be
and replacement
for
paragraphs,
is ap-
of
(1) Remove the spark plug hole. Rotate the crankshaft in direction of normalrotation until the compression stroke is reached, this is indicated bya positive pressure inside the spark normal rotation until the the starter ring at
the two o'clock position on the Consult specification At this point, the engine
a spark plug from No. 1 cylinder
plug hole. Continue rotating
gear is in exact alignment with
the cylinder tending to
the crankshaft in direction
advance timing mark on the
front face of the starter
for correct timing mark for
is ready for assembly of the
and place a thumb over
push the thumb off
front face of
the small hole located
housing.
your installation.
magnetos.
5-1
of
LYCOMING
OPERATOR'S
MANUAL
SECTION 5
0-235
AND 0-290
SERIES
5-2
FIRING
Figure 5-1. Ignition Wiring Diagram
ORDER
1-3-2-4
LYCOMING OPERATOR'S MANUAL
0-235 AND 0-290 SERIES SECTION 5
Figure 5-2.
FIRING ORDER 1-3-2-4
Ignition Wiring Diagram
(Optional)
5-3
LYCOMING
OPERATOR'S
MANUAL
SECTION 5
0-235 AND
0-290 SERIES
5-4
Figure
FIRING ORDER 1-3-2-4
5-3. Ignition
Wiring
Diagram
(Optional)
LYCOMING OPERATOR'S MANUAL
0-235 AND 0-290 SERIES SECTION 5
All timing one cylinder advance engine magnetos.
The
method of positioning the cylinder advance engine firing position is contained in the followingparagraphs. The method for Bendix magnetos may be found on page 5-6.
(Impulse Coupling Magneto) Hold the No. 1 lead wire spring 1/16 in. to
1/8 in. away from the magneto
click at a time until a strong spark jumps between the spring and theframe. Hold the the
point where it trips and the proximately 25 until vent plug hole. Hold the rotor by inserting the timing pin, and line thetiming pin with the center of the vent plug hole.
(Conventional Magneto) Hold the No. 1 lead wire spring 1/8 in. awayfrom the frame. flux
lines until a strong spark occurs
to the
flux until the timing pin hole
hole and insert
procedures, except positioning
firing position, are the
Slick magnetos in the number
frame and turn the impulse
magneto firmly so the coupling
spark occurs. Reverse the rotation
the timing pin hole appears
Turn the gear counter-clockwise
at the lead. Reverse the rotation
appears in the center of the vent
the timing pin into
the hole.
the magneto in the number
same for all
one
coupling one
will not move beyond
ap-
in the center of the
vigorously through the
in-
plug
5-5
LYCOMING OPERATOR'S MANUAL
SECTION 5 0-235 AND 0-290 SERIES
NOTE
If the crankshaft is accidently turned in the direction opposite normalrotation, repeat the above procedure as accumulated backlash will makethe final timing incorrect.
(2) Remove the inspection plugs from both magnetos and turn thedrive
shafts in direction of normal
chamfered tooth on the distributor gear is aligned in the center of
the inspection window. Being sure that the gear does not move fromthis position, install gaskets and magnetos on the engine. Securewith washers
and nuts; tighten
NOTE
rotation until the first
only finger tight.
painted
In order to turn
pawl
on the
(3) Using a battery powered timing light, attach the positive lead toa suitable terminal connected to the ground terminal of the magnetoand
the negative lead to any unpainted the magneto in its mounting on,
then slowly turn it in the opposite out. Bring the magneto back slowly until the light just comes on.Repeat this with the second magneto.
Some
timing lights operate in the light comes on when the breaker points open. Check your timing light in-structions.
(4) After both magnetos have to
ascertain that both magnetos
(5)
Back off the crankshaft a few out. Bring until
the timing mark and the alignment. Tighten nuts
c. Generator or Alternator Output -The generator or alternator(whichever is applicable) should be checked to determine that thespecified voltage and current are being obtained.
the shaft on an impulse coupling
impulse coupling
the crankshaft slowly back
At this point, both lights
to specified torque
with
the finger.
flange to a point where the
NOTE
reverse manner as described above,
been timed, check, as described
are set to fire simutaneously.
degrees, the timing lights should
hole in the starter housing
(150 inch pounds).
magneto, depress the
portion of the engine.
direction until the light
in direction of normal rotation
should go on simultaneously.
Rotate
light comes
goes
the
below,
go
are in
LYCOMING OPERATOR'S MANUAL
0-235 AND 0-290 SERIES SECTION 5
2. FUEL SYSTEM.a. Repair
is replaced, only a fuel soluable lubricant, such as clean engine oil orLoctite Hydraulic Sealant, may be used on the threads. Any otherthread lubricant
b. Carburetor Inlet
distortion or openings
ditions. Clean assembly in
stall
in the throttle
c. Fuel Grades
subject engines is listed in the Engine Flight Chart on page 3-8 of thismanual. In the event locations, it is octane then specified is not to be used. Under no circumstances shouldautomotive
These engines are equipped with solid stem valves and should use higher
octane fuel only for limited
be familiar with Service Instruction No. 1070 regarding specified fuel for
Avco Lycoming engines.
d Air Intake Ducts and Filter -Check all air intake ducts for dirt or
restrictions. Inspect and service air filters as instructed in the air-frame manufacturer's handbook.
e. Idle Speed and Mixture Adjustment -
(1) Start the engine and warm up in the usual manner until oil andcylinder head temperatures are normal.
of Fuel Leaks -In the event a
or compound
Screen Assembly -Remove
in the strainer. Replace for
the screen asembly, place the
body, then tighten to
and Limitations -The recommended
that the specified fuel is not
permissible to use higher octane
fuel be used (regardless
must not be used.
solvent and dry with compressed
NOTE
operation. It is recommended
line or fitting in the fuel system
and check the screen for
either of these con-
air. To in-
gasket on the assembly and
35 -40 inch pounds torque.
aviation grade
available at some
fuel. Fuel of a lower
of octane rating).
that personnel
install
for
(2) Check magnetos. If the "mag-drop" is normal, proceed with idleadjustment.
(3) Set throttle stop screw so that the engine idles at the airframemanufacturer's recommended idling RPM. If the RPM changesappreciably after making idle mixture adjustment during the suc-ceeding steps, readjust the idle speed.
LYCOMING
OPERATOR'S
MANUAL
SECTION
5
(4) When the idling speed mixture control lever
0-235 AND 0-290
has been stabilized, move
with smooth, steady pull toward
SERIES
the cockpit
the "Idle Cut-Off" position and observe the tachometer for any change during theleaning process. Caution
must be exercised to
return the mixturecontrol to the "Full Rich" position before the RPM can drop to apoint where the engine cuts out. An increase of more than 50 RPMwhile "leaning"
out indicates an excessively
rich idle mixture. Animmediate decrease in RPM (if not preceded by a momentary in-crease) indicates
the idle mixture
is too lean.
If the above indicates that the idle adjustment is too rich or toolean, turn the idle mixture correction,
and check this new
procedure. Make additional
adjustment in the direction
position by repeating the
adjustments as necessary
required for
above
until a checkresults in a momentary pick-up of approximately 50 RPM. Eachtime the adjustment is changed, RPM to clear the engine Make the final
adjustment of the idle speed
the desired idling RPM
before proceeding with
with closed throttle. The
the engine should be run
adjustment to obtain
above method aims
up to 2000
the RPM check.
at a setting that will obtain maximum RPM with minimum manifoldpressure. In case the setting does not remain stable, check the idlelinkage; any looseness in this linkage would cause erratic idling. Inall cases,
allowance should be made for
the effect of weather condi-
tions and field altitude upon idling adjustment.
3. LUBRICATION SYSTEM.a. Oil Grades and Limitations -Service the engine with grade recom-
mended in Flight Chart, Section 3-8.
b. Oil Sump Capacity -
0-235 Series ..................................6 U.S. Quarts
0-290-D and -D2 Series ..........................8 U.S. Quarts
Minimum Safe Quantity in Sump .................2 U.S. Quarts
c. Oil Suction and Oil Pressure Screens. For engines without a full-flow
oil filter, change oil and inspect and clean screens every 25 hours.
NOTE
On installations employing full-flow oil filters, step c. is not practical atthis time, but should be observed at the 100 hour inspection.
5-8
LYCOMING OPERATOR'S MANUAL
AND 0-290 SERIES
0-235
c. Oil Relief Valve -Subject engines are equipped with either an ad-
justable
crankcase half to the rear will maintain the oil pressure adjusting pressure. The non-adjustable valve can control pressure by the addi-tion of a maximum of nine pressure
pressure.
d Oil Relief
the operator to maintain
If the pressure exceed the follows:
With the engine warmed RPM, observe the reading above screw the adjusting screw pressure. Depending on installation, ly a screw driver slot the turned with either a screw driver or a box wrench.
4. CYLINDER
disassembly field operation, cylinder entire assembly. Valve replacement should be undertaken only as anemergency measure.
or a non-adjustable oil
of no. 3 cylinder pad. The adjustable
screw inward to increase
STD-425 washers under the cap
or a spacer (P/N 73629 or 73630)
Valve (Adjustable) -The adjustable
engine oil pressure within
under normal operating conditions
maximum or minimum specified
on the oil pressure gage.
maximum or below minimum
out to decrease pressure and
and is turned with a screw
screw driver slot plus a pinned
ASSEMBLY. Although the
and reassembly is given here,
maintenance be confined to
relief valve located in the
within specified limits by
pressure and outward to
under the cap to decrease
oil relief valve enables
the specified limits.should consistently
limits, adjust the valve
up and running at approximately
specified limits, stop engine
the adjusting screw
driver; or may have
.375-24 castellated nut and
complete procedure for
it is recommended that, as
SECTION
right
valve
screwing the
decrease
to increase
as
2000
If the pressure is
and
in to increase
may have on-
may be
replacement of the
5
a
a. Removal of
Remove exhaust
(1) (2) Remove rocker box drain
clips that interfere
Cylinder Assembly
manifold.
with the removal
-
tube, intake pipe, priming
of cylinder.
lines and any
LYCOMING
SECTION 5 0-235 AND 0-290 SERIES
OPERATOR'S
MANUAL
(3) Disconnect ignition cable Remove
approximately (4) Remove
enabling removed when the
(5) Remove shroud tube.
(6) Remove the crankcase. as the piston falling.
The tappets, push rods, rocker that they can be assembled
removed.
Removal of Valves
b.
cylinder tion. Remove the split ings and valve head. Hold the valve stems so that the valve will not fall out andremove the cylinder from the holding block. The valves may now beremoved from the inside of the cylinder.
rocker box
at top
valve rockers
the valve rockers to be removed.
cylinder is taken from
push rods
cylinder
leaves the cylinder.
over a block
Compress the valve springs
base nuts and
Do not
and Valve
of wood so
keys from the end of the valve
spring seats may now be removed
at spark plugs and remove
cover and rotate
center of the
by sliding
by grasping the
allow the piston
Hold
NOTE
arms and valves must be
in the same location from which
Springs from
as to hold the
using the valve spring compressor.
crankshaft
compression
the valve rocker
Valve rocker shaft can the engine.
ball end and
pull cylinder
to drop against shroud tubes
Cylinder -
valves in a closed
stem. The valve spr-
spark plugs.
until piston
stroke.
shaft aside
pulling rod out
directly away
the crankcase
to prevent their
identified so
they were
Place the
from the cylinder
is
be
of
from
posi-
c. Removal
plugs. then proceed on cylinder pad discarded cylinder base
5-10
of Piston from Connecting
Insert piston pin puller through
to remove
of the crankcase. Support
Rod -Remove the piston
piston pin, assemble puller
piston pin. Do
oil ring seals or any other
not allow connecting
with heavy rubber bands,
method.
rod to
pin
nut;
rest
LYCOMING OPERATOR'S MANUAL
0-235 AND 0-290 SERIES SECTION 5
d Removal of Hydraulic Tappet Sockets and Plunger Assemblies -
(0-290-D2 Series) It will be necessary to remove and bleed the
hydraulic checked when ed in the following manner: A special Avco Lycoming tool is available
for removal of the sockets and plunger assemblies. In the event thetool is not available,
The hydraulic tappet socket may usually be removed by inserting
the forefinger ly stick to the finger
If the grasping However, care must be exercised remove Lycoming service tool. In the event that the tool is not available, thehydraulic tappet plunger assembly in the end of a short piece of lockwire, inserting the lockwire aroundthe edge of the plunger hook engages assembly out of the tappet body by gently pulling the wire.
Never use a magnet to remove hydraulic plunger assemlies from thecrankcase. This can cause the check ball to remain off its seat rendering
the unit inoperative.
tappet plunger assembly so
the cylinder assembly is reinstalled.
proceed as described
into the concave end of the
firmly enough to be pulled
socket cannot be removed
the edge of the socket with
the hydraulic tappet plunger
assembly, and turning the
the spring of the plunger
CA UTION
that dry tappet clearance can
This is accomplish-
below.
socket. The socket will usual-
in this manner, it may be removed
to avoid scratching
may be removed by bending
out of the tappet body.
a pair of needle nose pliers.
assembly, use special
assembly. Draw the plunger
the socket. To
Avco
a hook
wire so that the
be
by
e. Assembly of Valves in Cylinder -Prelubricate valve stems with
Molytex Grease 0 or equivalent and insert each valve stem in its
respective
valves are held against the seats and assemble the lower valve springseat, auxiliary valve seat and outer valve spring over the valve stem
and guide. Place the upper valve spring seat on top of the springs.
When wound coils marked with dye or lacquer) toward the cylinder.
valve guide. Place cylinder
NOTE
installing valve springs, place
over a block of wood so
the dampener end of spring
that the
(close
LYCOMING OPERATOR'S MANUAL
SECTION 5 0-235 AND 0-290 SERIES
Using a valve spring compressor, compress the valve springs andplace the split keys in the groove around the upper end of the valvestem. Slowly release the pressure allow the upper spring seat to lock itself in place around the valvekeys.
f Assembly of Hydraulic Tappet Plunger Assemblies -(0-290-D2Series) To assemble the unit, unseat the ball by inserting a thin cleanbronze wire through the oil inlet hole. With the ball off its seat, insertthe plunger and twist clockwise so that the spring catches.
g. Assembly of Cylinder and
that the connecting rod of the cylinder being assembled is at the top
center position with both tappets on the low side of the cam in a posi-
tion that corresponds with both valve closed.
(1) 0-290-D2 Series -Place each hydraulic tappet plunger assembly inits respective body and assembly socket on top of plunger assembly.
Assemble piston so that the
(2) piston pin boss is toward the front end of the engine. The piston pinshould be a push fit. If difficulty is experienced in inserting thepiston pin, it is probably caused by carbon or burrs in the piston pinhole. During assembly, always use a generous amount of oil, both inthe piston pin hole and on the piston pin.
(3) Assemble one piston pin plug at each end of the piston pin andplace a new cylinder base oil seal ring around the cylinder skirt. Coatpiston, rings and the inside of the cylinder generously with oil.
(4) Using piston so that the intake and exhaust ports are toward the bottom ofthe engine.
a piston ring compressor,
on the valve spring compressor
Related Parts -Rotate the
cylinder number stamped
assemble the cylinder over the
crankshaft so
and
on the
(5) Push the cylinder down onto the cylinder mounting studs.(6) Insert a new shroud tube (7) Pull the cylinder back far enough to insert one end of each shroud
tube into position in the cylinder head, and hold shroud tube so thatrubber seals will enter the seal seats in the crankcase. Push thecylinder all the way down.
oil seal over each end of
shroud tube.
LYCOMING
OPERATOR'S
MANUAL
0-235 AND 0-290 SERIES
NOTE
Before installing
thru-stud
1. 90% SAE 50W engine oil and 10% STP.
2. Parker Thread Lube.
3. 60% SAE
(8) Assemble directed in the
At anytime studs on the cylinder
(a) Tighten the pounds with the
(b) Repeat the above to 600 inch
420 inch pounds
cylinder base hold down nuts,
threads with any
30W engine oil and 40%
one of the following lubricants.
the cylinder base hold
following
a cylinder
on the opposite side
steps.
NOTE
is replaced, it
1/2 inch or 7/16 inch hold
(25 foot
pounds) torque
upper right hand nut and proceed
steps and tighten the 1/2 inch
pounds (50 foot pounds)
(35 foot pounds)
Parker Thread Lube.
is necessary to
in the following
torque
stated.
SECTION 5
lubricate the crankcase
down nuts and tighten
of the engine.
retorque the thru-
down nuts to 300 inch
sequence:
Begin
in a clockwise direction.
hold down nuts
or 7/16 inch hold down nuts
using the exact
sequence
as
to
(c) Tighten the 3/8 inch hold pounds) torque;
Some 0-235 Series engines
these nuts ing sequence
to 300 inch pounds (25 foot pounds)
stated in step
sequence of tightening
(d) As a final check five seconds.
If the nut does not turn,
tightened to the correct torque.
down nuts to 300 inch pounds
is optional.
NOTE
employ only 3/8 inch hold
torque using the tighten-
(a).
hold the torque wrench on
it may be presumed to
(25 foot
down nuts. Tighten
each nut for about
be
5-13
LYCOMING OPERATOR'S MANUAL
SECTION 5
all cylinder
After
cylinder
fins by filing
Assemble
(9) assemble between rocker.
(10) 0-290-D2
pression
the valve
ween
clearance,
the end of
over hydraulic
check valve
the clearance
If rod and clearance.
Inserting
(11) 0-235,
compression adjusting clearance following
nuts have
base
or burring.
each push
rocker
each
bosses
Series -
stroke
place the
tappet
clearance,
insert a longer
long rod
a
0-290D
stroke
screw
between
manner:
sliding
and
Be sure that and that stem tip
thumb of
the push
spring. While
not come
does
will cause
Series
and
in valve rockers
the valve
CAUTION
tightened
been
rod in
in its
both valves and the
rod and
which
or shorter push
-Be sure that
its respective respective valve rocker
valve rocker.
one hand
push down
holding should
within these
NOTE
a decrease
both
and
and
tip
0-235 AND 0-290
remove
position
shaft
the piston is at
are closed.
on the valve
be between
that the
valves
using clearance
valve rocker.
Check
In order
so as to
spring
the
.028
limits,
rod, as required
valve clearance.
in
piston
are closed.
SERIES
nicks
any
shroud
by placing
in place
tube,
to retain
top center com-
clearance
to check
directly
rocker
compress
compressed,
and .080
remove
the push
to correct
is at top
Assemble
adjust
gage
Adjust
in the
and
rocker
bet-this
the
inch.
center
the
in the
Set tappets clearance After
(12) All Engines
drain harness.
5. GENERATOR
belt 25 methods
after run-in,
adjusting,
tubes and
hours after installation.
checking generator
of
.007 in.
with
DRIVE BELT
clearance
the adjusting
lock
-Install gaskets exhaust
manifold.
-.009 in.
TENSION.
Refer
drive
clearance
should
and rocker
to Service Instruction
be from
screw
Install
Check the tension
belt tension.
cold. Recheck
.006 in.
in place
box covers,
spark plugs
with the
tappet
to .012
intake pipes,
and
No. 1129
in.
locknut.
ignition
of a new
for
LYCOMING OPERATOR'S MANUAL
TROUBLE-SHOOTING
Page
Failure Failure of Engine Low Power and Uneven Running Failure of
Rough Engine Low High Oil Temperature Excessive Oil Consumption