MVVS 58 IRS - V1.2, MVVS 58 IRS, MVVS 58 LC, 3002 Operating Instructions Manual

Operating instructions

MVVS 58 IRS / LC #3002

Version 1.2

Before using the engine, please read these instructions carefully.

Congratulations on choosing the gas engine MVVS 58 liquid cooled (LC).
MVVS 58 LC has been designed and manufactured for propeller-powered radio-controlled model planes
especially for those where is air cooling complicated.

Technical specifications

Bore 42 mm Maximum power output** 8,5 HP / 6950 RpM
Stroke 42 mm Maximální torque** 8,8 N/m / 6600 RpM
Weight of complete
engine without ignition *

1830 g Fuel

Unleaded fuel

95 octane

Weight of ignition unit 165 g Lubrication

Oil with petrol in

mixture 1:40

RpM range 1000 – 7500 RpM
* Some manufacturers state the weight of incomplete engines. The value in the table above stands for the
weight of a completely assembled engine, including the spark plug, carburetor, drive washer and prop
screws.
** Power output varies with the exhaust used. The value given in the table stands for the maximum
available power output.

Safety precautions

1) Never use the engine for any manned vehicles.

2) When operating model planes, always follow the rules and laws in effect in your country.

3) The manufacturer declines all responsibility for all damages arising from the operation of models and

other appliances droved by MVVS 58 engine.

4) Always use original spare parts.

5) Never tamper with the engine construction.

6) Before each flight check that all the propeller screws are tightened up and in good condition. If you

use a spinner, check that it is tightened up, too. When mounting the spinner always follow the
assembly instructions.

7) Periodically check that the engine is firmly fixed to the engine mounts. Never start a loose engine!

8) Always use a balanced propeller! Always replace the propeller when damaged!

9) Make sure that no part of your body intersects the plane of the spinning propeller.

10) Always wear close-fitting, well-fastened clothes when starting or operating the running engine. Never

wear loosely hanging clothes (ties, scarf, etc.).

11) Never try to stop the engine by any part of your body.

12) Always stop the engine either by turning off the ignition switch or by completely closing the

carburetor throttle valve.

13) Before starting the engine make sure that the model is safely fixed in place and cannot start moving.

14) Fuel is combustible and therefore must be kept in an enclosed container at a safe distance from the

engine when it is running.

15) When preparing fuel carefully follow the manufacturer’s or dealer’s instructions.

16) Small objects must be kept at a safe distance from the engine when it is running. Never throw any

objects towards the spinning propeller.

17) Be careful in choosing the location where you wish to start the engine. Avoid dusty or sandy areas.

18) Start the engine in well-ventilated areas only. Never start the engine indoors.

19) When starting the engine make sure that bystanders, especially children, are at a safe distance of at

least 10 m.

20) The engine power output makes it possible to fly big models. Mal-operation of such models may

cause serious damage. Start using the MVVS 58 in model planes only after you have mastered
operating smaller models.

Selecting a suitable propeller

It is usually the case that propellers of the same dimensions coming from different manufacturers are not the
same. Oftentimes not even propellers of the same dimensions produced by a same manufacturer are not the
same. The engine power is best utilized when the propeller dynamics curve and engine power curve
(revolutions / power output) intersect in the area of the engine top power output. Unfortunately, no propeller
manufacturer provides this information. Engine power output is also a variable quality. It depends above all
on the silencer used and can considerably vary. The situation is further complicated by environmental
parameters (temperature and atmospheric pressure in particular): low temperature and high pressure
increase propellers’ input requirements by 20% in comparison with input at hot weather.

MVVS 58 has been designed to generate maximum power at 6800 – 7100 RpM, according to the type of
exhaust used. If you wish to utilize the maximum power output, choose a propeller, which allow the engine
to reach these revolutions, or slightly lower revolutions (given the unloading of the propeller depending on
the speed of flight) on the ground.
We do not recommend using propellers with which the engine reaches more than 7500 RpM on the ground.

Suggested propeller dimensions: two-blade: 22x10, 22x12, 22x14

24x8, 24x9, 24x10, 24x12
25x7, 25x8, 25x9, 25x10, 25x12

26x7, 26x8, 26x9, 26x10
three-blade 22x10, 22x12, 24x9, 24x10, 24x12
These values are only approximate and may vary with the factors described in the previous section, as well
as with the type of the exhaust system used.

Fuel

Always use unleaded 95-octane petrol mixed in the proportion 40 volume units of petrol to 1 unit of Mobil
Racing 2T oil. If necessary, quality brand-name synthetic oil intended for racing two-stroke engines
can be used too. Running the engine in, use MVVS Racing 2T oil which comes with the engine. Mix it in
the proportion 30:1.
Never use inexpensive oil developed for garden appliances or synthetic oils intended for the operation of
methanol model engines. The manufacturer declines all responsibility for all engine damages arising from
the use of low-quality fuel.
Store fuel in containers designed for this purpose. Do not use mixed fuel older than 90 days.

Assembly

The engine is fastened in place with four holders built in the rear cover. The rear cover is adjustable by 90°
which ensure easy access to the carburetor’s operating elements. The engine can be mounted directly to the
firewall or an assembly kit can be used (special accessories). Use M6 screws or screws M5 with a reduction
kit (special accessories). If you decide to fasten the engine using flexible motor mounts, always choose parts
with enough solidity and strength. Make sure to secure the screws against loosening and regularly check
that they are tightened up and in good condition. Position of carburetors difuzors should be placed at least
50mm from firewall.

Engine is water cooled so it is not necessary so intensive air flow under cowl. However some ventilating
around engine is needed to guarantee intake of cool air.

Ensure access of air to the engine intake as well. Caution: intake of warm air from beneath the cowl may
cut the engine power output.

Note: Attach a hose to the airpressure inlet on the carburetor and terminate it outside the cowl.

Caution! When mounting the engine in the model use seals to protect all openings and prevent the
pollution of the engine’s inside with sawdust, residual abrasives etc. Make sure that the inside of the
fuselage is clean and that all parts are tighten in place and cannot be sucked inside the engine.

Exhaust

Use only factory-made exhausts pipes designed for this type of engine, preferably brand-name MVVS
engines with which you also get the power output guaranteed.
The manufacturer declines all responsibility for all engine damages arising from the use of improper
exhaust systems.
When mounting the exhaust follow the manufacturer’s instructions. Make sure to secure sufficient cooling
of the exhaust.

Cooling system

Engine is cooled by water circulation between cylinder and cooler. Forced circulation is caused by dentil
pump powered by crankshaft (connected by elastic strap). This conception allows placing engine to
aircrafts where cooling by air is very complicated. It is recommended to use the same conception as shown
in picture below. It is necessary to purchase MVVS radiator kit (cat. no. 3370 – contains: cooler, hoses and
filling part) in order to make the engine work. In case that size of standard cooler is not suitable to your
needs it is possible to order size on you own request by your dealer or from producer directly.
Use distill water without any other addition in the cooling system. Empty the system when engine is out of
season. If you are going to store model with engine in place where might be frost always empty whole
system to avoid possible destruction of cooling system, cylinder and pump.