Folks,
I am Brazillian so make an allowance and forgive my english writing.
Recently a friend of mine bought an used RV7A with a LYCOMMING YIO-360-M1B (180HP). This plane had a history of incident with main gear failure and flip.
It was repaired with the insurance company money from a reputed company that made all tests to the engine and complete rebuilt the airframe.
After the purchase... We've flown couple hours on the plane without problem on take off or cruise except a great difficulty in maintaining it at idle or bellow 1200 rpm for warm up when starting cold.
But even after a flight (with the engine already warm) when I quick stop in pump for refueling after re-starting it was again dying on idle with much gasping and choking. And it seems to be getting worse...
We notice also some loise "shots" from the exhaust sometime on take off or when we idle it on final.
It got worse, last flight had to be aborted because the engine had vibration on high RPM , noise a bit out of common and was noticeably producing less power that I was used to have...
I TALKED to a mechanic that had not time yet to verify it , but he will.
Before that I would like any opinions on what could be the cause for an engine that was behaving ok on one week had such fast degrading simptoms.
- Magnetos tests where a bit high but about normal , 200 rpm drop and same on both magnetos...
- Propeller pitch test producing drop as expected and re-establilish values after..
But the engine continues to behave badly on idle or low rpm (dying) and also in take off power (vibration , shots from exhaust an seems to produce much less power than expected)
I thought:
- Spark plug oil-fouled - if so why I was not able to dry it on low mixture (tryed for 2 min!)?
- Contant Speed governor was unable to bring the propeller pitch to the correct take off position (less probable to be the cause)
- Others....( injection settings? )
Obs: Engine is in break in period after having being inspected and rebuilt.
Could anyone point other probable causes of the power loss, exhaust shots and dying at low RPMs?
Thanks in advance.
I am Brazillian so make an allowance and forgive my english writing.
Recently a friend of mine bought an used RV7A with a LYCOMMING YIO-360-M1B (180HP). This plane had a history of incident with main gear failure and flip.
It was repaired with the insurance company money from a reputed company that made all tests to the engine and complete rebuilt the airframe.
After the purchase... We've flown couple hours on the plane without problem on take off or cruise except a great difficulty in maintaining it at idle or bellow 1200 rpm for warm up when starting cold.
But even after a flight (with the engine already warm) when I quick stop in pump for refueling after re-starting it was again dying on idle with much gasping and choking. And it seems to be getting worse...
We notice also some loise "shots" from the exhaust sometime on take off or when we idle it on final.
It got worse, last flight had to be aborted because the engine had vibration on high RPM , noise a bit out of common and was noticeably producing less power that I was used to have...
I TALKED to a mechanic that had not time yet to verify it , but he will.
Before that I would like any opinions on what could be the cause for an engine that was behaving ok on one week had such fast degrading simptoms.
- Magnetos tests where a bit high but about normal , 200 rpm drop and same on both magnetos...
- Propeller pitch test producing drop as expected and re-establilish values after..
But the engine continues to behave badly on idle or low rpm (dying) and also in take off power (vibration , shots from exhaust an seems to produce much less power than expected)
I thought:
- Spark plug oil-fouled - if so why I was not able to dry it on low mixture (tryed for 2 min!)?
- Contant Speed governor was unable to bring the propeller pitch to the correct take off position (less probable to be the cause)
- Others....( injection settings? )
Obs: Engine is in break in period after having being inspected and rebuilt.
Could anyone point other probable causes of the power loss, exhaust shots and dying at low RPMs?
Thanks in advance.
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