rrc1962
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- Jul 19, 2014
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This started a few weeks ago where it's been hard to start hot. It's a carb'd O-540. Yesterday I got stuck at an airport for about 2 hours. We tried everything to start it. Treated it like it was flooded, gave it more prime as of it were cold, and nothing. We pulled a top and bottom plug and even after intentionally trying to flood it so we had a definitive starting point, the plugs were bone dry. We worked at it for a punt an hour wi h a jump cart on it, gave up, went and got lunch, returned in about an hour, gave it 4 shots of prime and it went off on the first blad. Mechanic there had no ideas.
Today I took it to my mechanic. They cleaned and gapped plugs, checked timing, cleaned air filter and did a compression check. They put it back together and off I went. Flew for 2 hours, parked, got lunch, came back 2 hours later, 4 shots of prime and it went off on the first blade.
Flew 20 minutes to a nearby airport to pick up my CFI, shut it off, came out 15 minutes later and nothing. Same as the day before. Acted like it had no spark. The mechanic there tried everything. He pulled plugs and again, bone dry. We put the jump cart on it and finally gave up. Went back to it a couple hours later and it went right off on a few shots of prime.
Now a question for the mechanics. Could this be an impulse coupler issue? Is there something in there like a condenser that could be going bad when it gets hot causing weak spark? Once it starts it runs great.
The other possibility is the carb. Near as we can tell, it hasn't been overhauled since the engine overhaul, which was in '89. Plan is to send it off at annual, which is happening later this week.
Today I took it to my mechanic. They cleaned and gapped plugs, checked timing, cleaned air filter and did a compression check. They put it back together and off I went. Flew for 2 hours, parked, got lunch, came back 2 hours later, 4 shots of prime and it went off on the first blade.
Flew 20 minutes to a nearby airport to pick up my CFI, shut it off, came out 15 minutes later and nothing. Same as the day before. Acted like it had no spark. The mechanic there tried everything. He pulled plugs and again, bone dry. We put the jump cart on it and finally gave up. Went back to it a couple hours later and it went right off on a few shots of prime.
Now a question for the mechanics. Could this be an impulse coupler issue? Is there something in there like a condenser that could be going bad when it gets hot causing weak spark? Once it starts it runs great.
The other possibility is the carb. Near as we can tell, it hasn't been overhauled since the engine overhaul, which was in '89. Plan is to send it off at annual, which is happening later this week.
