Ok, bear with me, this may be a long post..
2 flights ago, during a cold start (on a chilly day) the plane fired right up and then quickly **** back down. This is abnormal for our 6. Normally always fires right up. Anyway, fired it right back up, started fine, searched for idle for a bit but stayed running.. Good runup, no issues. Went flying.
Today, the same deal. Fired up, shut back down, fired back up and zero issues. Good runup, went flying. No issues.
Fly for about 30 minutes. Land. Plane sits for about 45 minutes, crawl back in, fire it up (starts fine), decently short taxi out, normal run up and depart.
While climbing out, above ~2250 rpm the engine starts running rougher than I like, pull the power back to around 2100rpm and all is fine. Turn downwind and land.
Taxi in and do a quick runup. Oil temps climb a littler higher than normal, about 240*ish, and the plane runs s rough at 2200 rpm and above.
Taxi in, pull the cowl, look it over. Everything looks normal, but there was a funny smell. Semi-electrical. Semi-heater on for the first time in winter. Semi-burnt electric motor type smell. Not a normal smell.
Let it rest, call our mech and he suggests mixture setting as the first place to start looking. Mixture was slightly off. We set it for about a 50rpm rise when killed from idle.
Do a couple quick run ups to about 2250rpm static and then idle shut offs messing with the mixture.
Taxi’d back out for a runup just to see how it’s acting. Run up is good until a few seonds into high power and it begins running rough again. Rpms drop to 2000-2100ish. Back to the hangar. Smell is kinda there, but nothing like the first time.
Call A&P and he suggests maybe it’s fouled plugs and to attempt to burn it off.
Taxi out, attempt to burn off plugs with high power/leaning on the ground and am unable to get steady enough running to really accomplish anything. EGT’s got to around 1250. No improvement.
Pull the power back and just for grins, I checked the mags. Nothing. No drop on either mag. Ah ha! I think. Found it.
Taxi back to the hangar and before shutting down, power back to ~1800rpm and check mags. Got about a 75rpm drop on both. Decent check.
I’m stumped.
Unmetered Air? Bad Venturi or float in the carb? Mags toasted?
Engine details:
Recent (<100 hours) rebuild O-320.
Bendix mags.
Running non-ethanol mogas.
2 flights ago, during a cold start (on a chilly day) the plane fired right up and then quickly **** back down. This is abnormal for our 6. Normally always fires right up. Anyway, fired it right back up, started fine, searched for idle for a bit but stayed running.. Good runup, no issues. Went flying.
Today, the same deal. Fired up, shut back down, fired back up and zero issues. Good runup, went flying. No issues.
Fly for about 30 minutes. Land. Plane sits for about 45 minutes, crawl back in, fire it up (starts fine), decently short taxi out, normal run up and depart.
While climbing out, above ~2250 rpm the engine starts running rougher than I like, pull the power back to around 2100rpm and all is fine. Turn downwind and land.
Taxi in and do a quick runup. Oil temps climb a littler higher than normal, about 240*ish, and the plane runs s rough at 2200 rpm and above.
Taxi in, pull the cowl, look it over. Everything looks normal, but there was a funny smell. Semi-electrical. Semi-heater on for the first time in winter. Semi-burnt electric motor type smell. Not a normal smell.
Let it rest, call our mech and he suggests mixture setting as the first place to start looking. Mixture was slightly off. We set it for about a 50rpm rise when killed from idle.
Do a couple quick run ups to about 2250rpm static and then idle shut offs messing with the mixture.
Taxi’d back out for a runup just to see how it’s acting. Run up is good until a few seonds into high power and it begins running rough again. Rpms drop to 2000-2100ish. Back to the hangar. Smell is kinda there, but nothing like the first time.
Call A&P and he suggests maybe it’s fouled plugs and to attempt to burn it off.
Taxi out, attempt to burn off plugs with high power/leaning on the ground and am unable to get steady enough running to really accomplish anything. EGT’s got to around 1250. No improvement.
Pull the power back and just for grins, I checked the mags. Nothing. No drop on either mag. Ah ha! I think. Found it.
Taxi back to the hangar and before shutting down, power back to ~1800rpm and check mags. Got about a 75rpm drop on both. Decent check.
I’m stumped.
Unmetered Air? Bad Venturi or float in the carb? Mags toasted?
Engine details:
Recent (<100 hours) rebuild O-320.
Bendix mags.
Running non-ethanol mogas.
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