Oil Mist Behind the Generator

How to keep the Cessna 170 flying and airworthy.

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Robert Eilers
Posts: 652
Joined: Sat May 08, 2004 12:33 am

Oil Mist Behind the Generator

Post by Robert Eilers »

I have been developing an oil mist on the fire wall behind the generator ever since I purchased the airplane. Never gets very serious just kind of a mist after a couple hours of flight. A quick wipe with a towel and it is gone. I suspect the mist is coming from the generator. There is no oil coming from the vent pipe at the back of the generatorand there is never any oil on the inside of the cowling under the generator, but there is always a drop at the opening under the generator up against the engine case. Any ideas?
Hineywheel Bill
Posts: 93
Joined: Fri Feb 17, 2006 8:55 pm

Post by Hineywheel Bill »

If it is in fact coming from the generator it would likely be the generator shaft seal that is leaking. The seal is inexpensive and is fairly easy to replace. Bill
scsmith42
Posts: 18
Joined: Fri Dec 15, 2006 3:33 am

Post by scsmith42 »

The oil temperature sending unit is also located right beneath the generator - another potential cause.
'53 170 B
N3134A
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