Exhausts
Use only factory-made exhausts pipes designed for this type of engine. Preferably MVVS
exhaust system, which also guarantees the announced power output. 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.
Carburetors adjustment
Both carburetors are adjusted before you buy it. It is not usually needed to change this
setting (always apply if used recommended exhaust system and propeller).
Caution! All settings make only if engine does not run. Injury may be caused by propeller.
Always set the same adjustments on both carburetors !
Basic setting:
adjusting needles (L) for low revolutions range: 2 turns
adjusting needles (H) for high revolutions range 1,5 turn
(the values are derived from the position of clock-hands, starting position: fully closed
needle)
Caution! Never tighten the adjusting needles with too much strength. This may cause
damage of the needles. If the needles are damaged this way it is no longer possible to adjust
the carburetor and it is necessary to exchange it for a new one.
The new engine comes adjusted to the basic setting. This setting should be kept during the
running in!
After the engine has been run in, adjust it following the instructions below:
- start the engine and warm it up
- let the engine run at idle speed for approx. 5 seconds
If the engine starts to run backwards do not open the throttle - stop the engine
immediately! Otherwise the engine could be damaged!
Step I
-
Accelerate to 2/3 of the throttle range within approx. 1 sec (faster acceleration). Repeat
three times – if the engine accelerates quickly and without a hiccup go to Step III. If
acceleration is not smooth go on to Step II.
Step II
-
Faulty acceleration with hiccups and a tendency to cut out is usually attributable to a poor
fuel mixture in the medium-revolutions range. Stop the engine and recheck the fuel feed (the
hose-pipe must not be pinched or broken; if fitted, check also the fuel filter permeability).
Restart the engine and test acceleration again. If problems persist adjust both carburetors.
Open the adjusting needles L by 5 min and retest acceleration. If acceleration is smooth,
open the needles by another 3-5 min - this should be done because the needle was previously
set at a boundary value; if atmospheric conditions changed during flight, the problems might
recur.
- If the engine continues to malaccelerate open the needles by 10 min if the engine’s
operation does not improve, stop it and check the basic setting. Set the adjusting needles L at
2 turn and the adjusting needles H at 1,5 turn . Restart the engine and test acceleration. If the
engine runs correctly go to Step III. If it continues to malaccelerate, open the needles by
another 10 min. If it keeps malaccelerate, the defect is likely to lie elsewhere than in
incorrect adjustment. In such a case, go to the section on problem solving.
Step III
-
If the engine accelerates correctly, according to the above test, set it at idle speed and
accelerate to full speed. Repeat twice more. If the engine functions correctly, go to Step IV.
If it cuts out, open the L needle by 5-10 min more.
- If the engine does not respond to acceleration fast enough keep closing the L needles until
the engine starts to cut out in response to gas. At that point reopen the L nozzle by 5-10 min.
Step IV
-
If the engine reacts correctly set it at full speed. If revolutions do not drop, the engine has
been adjusted successfully. If revolutions seem to drop, open the adjusting needles H by
approx. 5-10 min.
Caution!!! Never close the choke valve completely when the engine is operating!
The choke valve is set to allow minimum air flow only when fully closed, which could cause
damage to the intake reed valve.
Содержание MVVS 190CN4
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