647jc
Well Known Member
I have a certified Lyc O-320, 160hrs since new with two Slick mags. The engine used to start fine, after a couple blades, no problems. About 9 months ago I noticed the engine did not want to fire when cranking until I released the key switch, I have a basic ACS switch.
So, my start scenario is, I prime the engine as needed, turn the keyswitch to start and the engine begins cranking over (I have a new battery also). I can crank the engine over for 4 or 5 seconds without any noticeable firing. Then, just when I release the key back to normal, the engine typically fires and starts. When it fires it hits pretty hard, probably because the right mag is firing and the timing is not retarded at that point. Once started, the engine runs fine, idles OK, run-up and mag check is good, engine runs great under power.
During my last annual I had an A&P check compression and mags. We verified the mag timing and proper operation of the ACS switch grounding the correct mag according to switch position and also verified the impulse coupler on the left mag was tripping at the correct time. But I still have the problem and I?m afraid I may damage the starter case with a kick-back since the engine is really starting on the right mag with no retarded timing. I have a metal Sensenich FP prop which has enough mass to pull the engine through the initial non-retarded firing but I think eventually I?m going to get a kick-back and destroy the starter.
Anyway, not sure what to do next, any additional tests I can perform? I?m ready to pull the left mag and send it in for re-work even though it only has about 160hrs on it? Any suggestions as to what shop would be best, I live in the Midwest?
So, my start scenario is, I prime the engine as needed, turn the keyswitch to start and the engine begins cranking over (I have a new battery also). I can crank the engine over for 4 or 5 seconds without any noticeable firing. Then, just when I release the key back to normal, the engine typically fires and starts. When it fires it hits pretty hard, probably because the right mag is firing and the timing is not retarded at that point. Once started, the engine runs fine, idles OK, run-up and mag check is good, engine runs great under power.
During my last annual I had an A&P check compression and mags. We verified the mag timing and proper operation of the ACS switch grounding the correct mag according to switch position and also verified the impulse coupler on the left mag was tripping at the correct time. But I still have the problem and I?m afraid I may damage the starter case with a kick-back since the engine is really starting on the right mag with no retarded timing. I have a metal Sensenich FP prop which has enough mass to pull the engine through the initial non-retarded firing but I think eventually I?m going to get a kick-back and destroy the starter.
Anyway, not sure what to do next, any additional tests I can perform? I?m ready to pull the left mag and send it in for re-work even though it only has about 160hrs on it? Any suggestions as to what shop would be best, I live in the Midwest?