Skywagon185
FRIEND
Bigfork, MT
Thought I'd post here to see if anyone has thoughts on this. Plane is a 79 185 with a Lycon built IO550D, 500 hours SMOH.
A few weeks ago I was flying along minding my own business when the engine began hiccuping. I noted all EGT's increasing and fuel flow varying (normally steady). Went full rich on mixture, no help. Then low boost on the electric fuel pump, no help. Now I'm starting to get nervous. Full boost on emergency pump, no help. Any increase in MP results in more engine skipping. I was able to limp it to a back country strip and land Ok. Decowled the engine to look for any obvious issues. Nothing, all looks good. Remove fuel strainer and screen, all looks good. Run full electric fuel pump boost to cycle fuel through system, checks OK. Fuel flow/pressure OK. Sump all tanks and drains, no water. Recowl, run up OK. Take off and fly in the pattern normally. Engine is running fine. Take off and fly home (high).
Once home I remove the screen on the mixture valve, clean. All seems well and the engine runs fine for another 10 hours. Fast forward to a couple of days ago. Firing up at another back country strip and the engine stalls. Never does that. Get it running and it seems fine. Fly home and upon shutdown it won't turn off. Engine diesels and coughs. Thought it might be due to a long low power decent. Get it running and let it run lean for a while and it shuts off. Now I'm concerned.
Next day I need to fly to the big city to get a pitot/static IFR cert on the bird. On take off I note reduced full power fuel flow (should be about 30gph). Only getting 22gph. Engine runs ok with full MP but the mixture settings are different than normal. Definitely some fuel flow issues. Limp it into the big city and now its waiting to be looked at by the local Cessna service center.
Thoughts? I'm thinking maybe an issue with the mixture cable travel or possibly a fuel pump?
A few weeks ago I was flying along minding my own business when the engine began hiccuping. I noted all EGT's increasing and fuel flow varying (normally steady). Went full rich on mixture, no help. Then low boost on the electric fuel pump, no help. Now I'm starting to get nervous. Full boost on emergency pump, no help. Any increase in MP results in more engine skipping. I was able to limp it to a back country strip and land Ok. Decowled the engine to look for any obvious issues. Nothing, all looks good. Remove fuel strainer and screen, all looks good. Run full electric fuel pump boost to cycle fuel through system, checks OK. Fuel flow/pressure OK. Sump all tanks and drains, no water. Recowl, run up OK. Take off and fly in the pattern normally. Engine is running fine. Take off and fly home (high).
Once home I remove the screen on the mixture valve, clean. All seems well and the engine runs fine for another 10 hours. Fast forward to a couple of days ago. Firing up at another back country strip and the engine stalls. Never does that. Get it running and it seems fine. Fly home and upon shutdown it won't turn off. Engine diesels and coughs. Thought it might be due to a long low power decent. Get it running and let it run lean for a while and it shuts off. Now I'm concerned.
Next day I need to fly to the big city to get a pitot/static IFR cert on the bird. On take off I note reduced full power fuel flow (should be about 30gph). Only getting 22gph. Engine runs ok with full MP but the mixture settings are different than normal. Definitely some fuel flow issues. Limp it into the big city and now its waiting to be looked at by the local Cessna service center.
Thoughts? I'm thinking maybe an issue with the mixture cable travel or possibly a fuel pump?
