Wren 44 Gold Helicopter Owners Manual
Page 22
Fire Extinguisher
Equip yourself with an appropriate fire fighting extinguisher whenever you are planning to
run your engine. The best extinguisher for our purposes is the Carbon Dioxide (CO
2
) or any
gas extinguisher. Use of dry powder, foam or water based extinguishers will cause serious
damage to the engine and should only be used as a last resort when there is nothing else.
DON’Ts.
Never mount the engine using self tapping screws – it is impossible to ensure they cannot
loosen or pull through. Use only cap head screws with nyloc type lock nuts
Do not use second hand fuel tube – it can harden with use and not allow a proper seal.
Silicone tube must
never
be used anywhere in the installation as it is dissolved by the fuel
and oil.
Do not install filters in the feed (suction) line from the fuel tank to the fuel pump. This is
known to cause aeration of the fuel and flow disturbances resulting in stoppages.
Do not use fuel which has not been properly filtered. Dirty or contaminated fuel can result in
blockages of the fine fuel injectors in the engine or blockage of the engine lubrication system
and subsequent bearing damage.
Don’t cut the fuel line between the filter and the engine as this can allow debris to enter the
engine fuel system which can cause severe damage to bearings and combustion system.
Do not try to run the engine without rotors fitted. The head can easily overspeed in a couple
of seconds and the excessive rpm can break the tail rotor.
Do not try to run the engine with just the clutch shoe drum fitted to the output shaft. If the
output shaft starts spinning fast it can cause the clutch shoes to snap off the drum and fly
outwards at great speed and can cause you or someone nearby, serious injury.
Don’t’ ever try to run the heli to speed by tying it down to a workbench or hard surface. It will
surely wriggle itself into a total wreck in a most dangerous manner. If you are lucky it won’t
get you but if you are not, those rotor blades are like a couple of bit swords….
BIG NOTICE
There is NO safe way to run your heli engine to full power on the ground
so please don’t try to.
The engine has already been test run to full power at the factory WITHOUT the 2
nd
stage fitted, during the build process and to set up the ECU.
You do NOT need to repeat this nor should you attempt it
.
