whoa is the .18 engine? first off you use a cordless drill with the clutch set on it to a low torque setting say 16-17,i've used the same drill for yrs on mine,but since you ripped up the roto start thats due to hydro locking the engine and you tried forcing it thru the lock,
a tiger drive will work but again if your using a heavy torque drill your gonna rip those up also,
get a good glow plug, if the coils don't glow bright orange then its crap, half a glow or dim glow wont get the proper ignition going.
a good glow plug are the o'donnell plugs depending on the fuel your running 20%?
also sounds like your a bit impatient, nitro cars can be iffy depending on fuels and glow plugs, as well as temps outside, air gets dense and people tend to start leaning the engine in to get a better response but all your doing is starving the engine of fuel and lubrication and increasing temps to high,
are your breaking in the engine properly? you need to get that engine to a temp of about 210* and hold it for about 2-3 tanks this will help stretch the sleeve properly around the piston, if start reving to high and you will stretch the conrod,
normal temps would be around 180-190* anything above 250* you start to head into the red zone of the reving.
