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SERVICE MANUAL
McCULLOCH
McCULLOCH
Model
Eager Beaver 2010,
Mac 3210
Silver Eagle 2012
Eager Beaver 2014,
Mac 3214,
Silver Eagle 2014
Eager Beaver 2016,
Mac 3216,
Silver Eagle 2016
MAINTENANCE
SPARK PLUG. Recommended
spark plug is Champion DJ7Y or equivalent for all models. Spark plug electrode gap is
models. Note that spark plug has a tapered seat and does not require a gasket. Tighten spark plug to 150 in.-lbs.
(17 N.m).
CARBURETOR AZamaClQM27
diaphragm type carburetor is used on
all models. Refer to CARBURETOR
SERVICE section for overhaul procedures and exploded views of Zama carburetors.
Initial a4justment for both the low-
speed and high-speed mixture screws is
one turn open from a lightly seated position. Make final adjustment with engine warm and running. Make certain
that the air cleaner is clean.
Adjust idle speed screw so engine
idles just below clutch engagement
speed. Adjust low-speed mixture screw
to obtain highest possible engine speed,
then turn screw out (counterclockwise)
1/8 to 1/4 turn. Engine should accelerate cleanly without hesitation. If en-
gine stumbles or seems sluggish when
accelerating, adjust low-speed mixture
screw until engine accelerates cleanly.
Readjust idle speed screw if necessary
to obtain recommended idle speed of
2800-3300 rpm. Chain must not move
when engine is idling.
High-speed mixture screw should be
adjusted to obtain optimum performance with saw under cutting load. Do
0.025
in. ( 0.6 mm) for all
Bore
36 mm
(1.4 in.)
36 mm
(1.4 in.)
36 mm
(1.4 in.)
36 mm
(1.4 in.)
not adjust high-speed mixture screw
too lean (turned too far clockwise) as
maximum permissible engine speed
may be exceeded and engine may be
damaged from lack of lubrication and
overheating. Maximum no-load speed
(with bar and chain installed) must not
exceed 11,000 rpm.
To remove carburetor (4—Fig.
MC130), remove the air filter cover (1)
and filter element. Remove the two
screws securing the filter base (3) and
carburetor. Remove the filter base and
carburetor, and disconnect fuel line and
throttle link. Tighten carburetor
mounting screws to 30-40 in.-lbs.
(3.4-4.5 N-m).
IGNITION. All engines are
equipped with an electronic ignition
system. The ignition coil and electronic
circuitry are contained in a one-piece
ignition module (10—Fig. MC130),
which is serviced as a unit assembly.
Air gap between the fiywheel magnets and the laminated legs of the module should be 0.010-0.015 in. (0.25-0.38
mm).
Loosen ignition module mounting
screws and move module to obtain desired air gap. If air gap is excessive, engine may bie hard to start or may not
start.
LUBRICATION. The engine is lu-
bricated by oil mixed with the gasoline
fuel. Recommended fiiehoil ratio is 40:1
when using McCulloch 2-cycle oil. If
McCulloch oil is not used, a good grade
oil designed for use in air-cooled,
two-stroke engines should be mixed at
Stroke
30 mm
(1.2 in.)
30 mm
(1.2 in.)
30 mm
(1.2 in.)
30 mm
(1.2 in.)
DispL
32 cc
(2.1 cu. in.)
32 cc
(2.1CU. in.)
32 cc
(2.1 cu. in.)
32 cc
(2.1CU. in.)
Drive
Type
Direct
Direct
Direct
Direct
a 20:1 ratio. Do not use oil designed for
automotive use. Use a separate container to mix the fuel and oil.
All models are equipped with an
automatic chain oiling system. Recommended oil is McCulloch Chain, Bar
and Sprocket oil. Oil designed for automotive use may also be used. Select oil
viscosity according to ambient temperature.
REPAIRS
CRANKCASE PRESSURE TEST.
An improperly sealed crankcase can
cause the engine to be hard to start, run
rough, have low power and overheat.
Refer to ENGINE SERVICE section of
this manual for crankcase pressure test
procedure. If crankcase leakage is indicated, pressurize the crankcase and use
a solution of soap and water to check
gasket, seals, pulse line and castings
for leakage.
PISTON, RINGS AND
CYLINDER. To remove the piston, it
is necessary to remove the powerhead
(12—Fig. MC131) and separate the cylinder from the crankcase as follows:
Unbolt and remove chain brake housing (13—Fig. MC131), bar and chain.
Remove the air filter cover (10), fan
housing (24), fiiel tank (7) and oil tank
(20).
Remove the ignition module, air
filter assembly, carburetor and muffler.
Remove spark plug and install a suitable piston stop tool or insert the end of
a rope in spark plug hole to prevent the
crankshaft from rotating. Note that fly-
Illustntions couit^y McCuUoch
Corp.
391
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McCULLOCH
CHAIN SAW
rod and cap. Install connecting rod on
crankshaft making sure that match
marks on rod and cap are aligned. Connecting rod and cap are fractured and
serration must mate correctly. Tighten
connecting rod cap screws to 35-40
in.-lbs.
(4.0-4.5 N-m).
CRANKSHAFT AND CRANK-
CASE.
Crankshaft (7—Fig. MC132) is
supported in two caged needle roller
bearings (10). Refer to PISTON section
to remove crankshaft from engine. Re-
move the connecting rod cap and sepa-
rate the connecting rod and piston from
crankshaft.
Inspect crankshaft and bearings for
wear or damage. Note that crankcase
and cylinder have mated surfaces and
must be renewed as an assembly. Apply
a thin coat of sealer to mating surfaces
of crankcase and cylinder during assembly. Tighten crankcase screws to
60-70 in.-lbs. (6.8-7.9 N-m). Make certain that the crankshaft rotates freely.
If not, disassemble and locate problem.
Tighten flywheel retaining nut to 180
in.-lbs.
(20.3 N«m). Do not use impact
tools to tighten flywheel nut and do not
over-torque, otherwise flywheel hub
can be cracked and distorted.
Fig. MC130—Expioded view of intake and exiiaust components.
1.
Shield
2.
Air filter element
3.
Filter housing
4.
Carburetor
5.
Gasket
6. Insulator
7.
Seal
8. Spacer
9. Gasket
wheel retaining nut has right-hand
threads (turn counterclockwise to remove) and clutch retaining nut has
left-hand threads (turn clockwise to remove).
Remove the flywheel nut and
tap flywheel counterbalance with a
plastic mallet to unseat the flywheel
(18—Fig. MC132) from crankshaft taper. Remove the air shroud (19) and oil
pump (15). Remove clutch retaining
nut (33) and withdraw the clutch as-
sembly.
Remove screws attaching the crankcase (27) to the cylinder (1), and separate the crankcase from the cylinder.
Care should be taken not to damage the
mating surfaces of the crankcase and
cylinder. Remove the crankshaft (7),
connecting rod (8) and piston (3) as an
assembly from the cylinder. Remove retaining rings (5) and push piston pin (4)
from the piston. Be careful not to apply
side thrust to the connecting rod when
removing the piston pin.
10.
Ignition module
11.
Muffler body
12.
Spacers
13.
Reinforcing plate
14.
Baffle
15.
Spark arrestor screen
16.
Baffle
17.
Muffler cover
Cylinder bore is chrome plated and
no oversize piston or piston ring is
available. If chrome plating is worn
away or if cylinder bore is scuffed or
scored, cylinder should be renewed.
Apply a thin coat of sealant to mating
surface of crankcase and cylinder when
assembling. Tighten the crankcase
screws to 60-70 in.-lbs. (6.8-7.9 N-m).
CONNECTING ROD. Refer to
PISTON section to remove connecting
rod (8—Fig. MC132) from engine. Remove rod cap to separate connecting
rod from crankshaft. Rod cap needle
bearings will be loose when rod cap is
removed.
Inspect connecting rod for worn or
damaged bearing surfaces. Connecting
rod should not be bent or twisted. Inspect crankshaft crankpin for wear or
scoring.
To reassemble, use grease to hold
bearing rollers in place in connecting
CLUTCH. To remove the clutch, de-
tach chain brake housing (13—Fig.
MC131), bar and chain. Remove the
spark plug and install a suitable piston
stop tool or insert the end of a rope in
spark plug hole to prevent the crankshaft from rotating. Clutch retaining
nut (33—Fig. MC132) has left-hand
threads (turn clockwise to remove). Remove retaining nut, dust cover (32)
clutch assembly (31), clutch drum (30)
and needle bearing (29).
Inspect all parts for signs of over-
heating and excessive wear. If neces-
sary to renew clutch shoes, renew as
complete set. Check sprocket for worn
rails and
pins.
Inspect the sprocket nee-
dle bearing for wear.
Tighten clutch retaining nut to 180
in.-lbs.
(20.3 N-m). Nut has left-hand
threads. The use of an impact wrench to
loosen or tighten clutch nut is not recommended.
AUTOMATIC CHAIN OILER. The
automatic chain oil pump is shown in
Fig. MC132. Remove the fan housing,
fljrwheel and air shroud for access to
the oil pump. A plunger gear repair kit
is available for the pump. Oil pump output is not adjustable.
CHAIN BRAKE. All models are
equipped with a chain brake that stops
the chain motion when the operator's
hand contacts the chain hand guard
(1—Fig. MC133).
TD
check for proper
392
Illustrations courtesy McCulioch Corp.
Page 3
SERVICE MANUAL
McCULLOCH
10
13
Fig.
MC131—Exploded
1.
Starter housing
2.
Rewind spring
3.
Rope handle
4.
Rope pulley
5.
Fuel primer bulb
6. Front handle
7.
Fuel tank
8. Heat shield
9. Fuel hose & screen
10.
Air filter cover
11.
Foam filter
12.
Powerhead
typical of alt modeta.
view of saw components
13.
Chain brake assy.
14.
Engine housing
15.
Throttle latch
16.
Throttle rod
17.
Return spring
18.
Throttle trigger
19.
Choke rod
20.
Oil
Unk
21.
Oil pickup hose & screen
22.
Stop switch contacts
23.
Stop switch button
24.
Fan hotising
chain brake operation, place saw on flat
surface and run at wide-open throttle.
Activate chain hand guard and chain
should stop moving immediately. Pull
hand guard rearward to disengage
brake. No adjustment of chain brake is
required. If brake fails to operate properly, disassemble and inspect for prob-
lem.
Tb disassemble chain brake, unbolt
and remove brake housing (8—Fig.
MC133) from saw. Engage the brake to
relieve spring tension. Remove brake
actuating lever (5) and carefully disengage spring
(6).
Remove brake band (9)
from housing.
Inspect all components for evidence
of wear or damage and renew as necessary. Brake band should be renewed if
any point is worn to a thickness of 0.020
inch (0.5 mm) or less.
23
24
When reassembling, lubricate pivot
points and latch engaging surface with
light coat of multipurpose grease.
REWIND STARTER, Tb disassemble rewind starter, remove starter
housing (2—Fig. MC134) from fan
housing. Remove rope handle (1) and
allow rope and pulley to slowly rewind.
Remove pulley retaining screw (5) and
withdraw rope pulley (4). Care should
be taken when removing rewind spring
(3) not to allow spring to unwind uncontrolled.
Inspect starter pawls (16—Fig.
MC132) and springs (17) for wear or
damage and renew as necessary.
Rewind spring is contained in a case
(3—Fig. MC134). If spring becomes disengaged from the case, it should be
wound into the case in a clockwise direction from outer end. Starter rope
length is 50 inches (127 cm). Wind rope
on pulley in clockwise direction viewed
from flywheel
TD
pre-tension rewind spring, com-
side.
plete starter assembly and pass rope
through housing outlet. Install rope
handle, then pull a loop of rope back
through the outlet and engage rope in
notch of rope pulley. Rotate pulley one
tum clockwise with rope in notch. Release rope from notch in pulley. Rope
should be held snugly against the
starter housing.
Pull rope handle and check rewind
operation. With starter rope fully extended, it should be possible to turn
pulley at least an additional 1/2 tum
clockwise. Be sure excessive tension is
not placed on rewind spring, otherwise
spring may break when rope is pulled
to its fiill length. Repeat spring pretension procedure until desired rewind
action is obtained.
Dlustrations county McCuUoch
Corp.
393
Page 4
McCULLOCH
33
Fig.
MC132'-Expioded view ofpowerhead typicai
1.
Cylinder
2.
Piston ring
3.
Piston
4.
Piston pin
5.
Snap ring
^^''^
6. Needle bearing
Crankshaft
Connecting rod
Seal
11.
Needle rollers
12.
Worm gear
13.
Spring
14,
Seal
15.
Oil pump housing
16.
Starter pawl
17.
Spring
^
7.
^-
8.
^.-f
9-
^ ^—tf'^Tjn 1^- Main bearing
of
CHAIN SAW
ail
models.
18.
Flywheel
19.
Air shroud
20.
"0" ring
21.
Washer
22.
Spring
23.
Oil pump plunger
24.
Plug
26.
Oil hose
26.
Adjusting screw
27.
Crankcase
28.
Washer
29.
Needle bearing
30.
Clutch drum
31.
Clutch hub & shoes
32.
Dust cover
33.
Nut
1.
Hand guard
2.
Brake stop
Brake latch
3.
394
Fig.
fACi33—Expioded
4.
Roller
5.
Actuating lever
6.
Brake spring
view of
chain braife
7.
Bar pad spacer
8.
Brake housing
9.
Brake hand
assembly.
10.
Foam seal
11
Shield
12.
Shoulder bolt
Fig.
fiAC134^Expioded
1.
Rope handle
2.
Starter housing
3.
Rewind spring & case
4.
view of rewind starter.
5.
6.
Illustrations courtesy McCulloch Corp.
Rope pulley
Screw
Fan housing
•
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