I flew home from EDNY to EGBE. After entering Belgian airspace my MP falls to 19.5, I was on FL160, so I descended to FL120.
I had minimal control about the MP, but decided to continue.
After landing I noticed the belly was covered in oil.
What happened?
The engine has about 250hrs after OH, and the turbo charger 200hrs from new.
Wastegate actuator leaking to its drain?
No, the actuator is just a cable.
If there was a leak in the charge air ducts then that would account for the drop in MP but not the oil.
Of course, a major mechanical malfunction would also result in the MP drop and the oil.
I think we need more clues!
The leak is quite right.
I lost about one liter of oil in under 4 hrs flight.
The more interesting question is why you didn’t land and continued over the channel to your destination. A sudden drop in manifold pressure can have many reasons and some of them can be very bad. Your exhaust could have cracked and now you have a fire spitting machine under the cowling that will destroy your aircraft.
Achim raises an interesting question…..
I had an exhaust cracking already and no drop in MP. You will notice a cracked exhaust quite quickly from the smell and the smoke.
…cracked turbocharger housing?
For the MP to drop that much, it means a lot of gas would have to escape and this would cause a lot of damage so that can’t be it.