maximum for a period of about one minute. At this point stop the engine and let it cool down. Then restart
it and check the adjustment. If everything is all right, you can first take off. During first few flights do not
overload the engine and do not let it run at high revolutions for long periods of time (very important at hot
weather). Use up all fuel that was produced as a mixture with the oil (we recommend the MOBIL Racing
2T). From now on, fuel and oil should be mixed in the proportion 40:1.
DO NOT PROCESS THE RUNNING-IN AT IDLE SPEED!
You should get following results if the engine is settled up and in run correctly
Engine
Propeller
RpM
Silencer
APC 16/12
8500-8700
3266
APC 16/10
9000-9300
3266
Mejzlik 18/10
8450-8550
3266
30 IFS
APC 18/6W
8200-8300
3270
APC 16/10
8400-8500
3270
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.
Possible faults of the engine and how to dispose those
If the engine does not start:
-
check and possibly replace the spark plug (check the spark: put the plug into the cable end and by
turning the engine you’ll see the necessary spark. Note: The plug must touch a metal part of the
engine.)
-
check fuel lines
-
check for proper mechanical function by turning the engine over
-
check that carburetor’s nozzles are adjusted correctly
-
remove the carburetor cover from the feed side; check the filter and blow off carburetor with
compressed air; (Caution: When using compressed air, use eye protection.) When re-assembling be
careful of maintain the proper order of the components
-
check the vacuum feed line
Mechanical faults (if the engine can not be turned over easily) must always be handled by a professional
service department
Service suggestions
After each 20 hours of running or 1 year change the spark plug.
After 100 hours of operation time commit the engine to the professional service department for check-up.
Re-assembling
These operations are very complicated and it is not recommended to do it on your own. Please commit to
professional service. Possible guide instructions we publish are as follows:
Demount rear cover, head and carburetor. It is not possible to re-assemble the engine unless the cylinder
part of the engine is heated up to 80° - 100°C. Then it is possible to remove steel piston insert without
rotating (!). Next step is piston and connecting rod removal. Crankshaft has to be in the top dead centre
(TDC). Pull off the connecting rod from pin on the crankshaft in direction to rear cover out of the
crankcase. After getting off the drive washer and Woodruff (safety) key, it is possible to pull out the
crankshaft again in direction to rear cover out of the crankcase. You will get the bearing out after heating
up (again between 80°- 100°C). Assembling passes off in opposite meaning.
