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                           Lom-List Digest Archive
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                     Total Messages Posted Fri 09/05/03: 1
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Today's Message Index:
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     1. 09:36 AM - Fuel in oil  (Jeayers1@aol.com)
 
 
 
________________________________  Message 1  _____________________________________


Time: 09:36:14 AM PST US
From: Jeayers1@aol.com
Subject: Lom-List: Fuel in oil

--> Lom-List message posted by: Jeayers1@aol.com

Hello Milos,

Fuel can leak through the fuel pump into the engine oil on engine 
installations in high wing aircraft or aircraft with header tanks.

The header pressure of the fuel into the fuel pump from either the fuel 
supply line or the return line causes fuel to leak through the fuel pump into the

engine oil.

On a high wing aircraft that had been setting for two weeks, the large fill 
port plug was removed from the oil cavity of the fuel pump.  Fuel was observed

to flow out of the oil cavity.
The cam case drain plug was removed to drain the oil, and three quarts of 
fuel and oil was drained from the cam case.
If the engine had been run prior to this inspection, the fuel contamination 
would not have been observed.

A symptom of this problem could be oil leaking out of the exhaust pipe, and 
oil at the slip joints in the exhaust pipe.  Unfortunately, the same symptom 
would occur from a leaking oil valve.

Fuel in the oil side of the fuel pump would be a direct method of observing 
the problem.

I have not seen this problem on my RV-3.  A low wing design without a header 
tank.

Best Regards,
Jim Ayers