Fuel in oil

by Keith Wall in 912 / 914 Technical Questions 7 years ago

I have a Aircam. 2 rotax 912. 7 months old with 100 hours. I just did my 2nd oil change. This time I requested an oil analysis. Both engines had fuel contamination. 5.8%. Viscosity was reduced. I don’t have fuel cutoffs. High wing tanks, gasolator, primer, electric fuel pumps which are only ran at start up.
Engines start and run great. No choke.
Any thoughts on what’s happening?

Re: Fuel in oil

by Roger Lee » 7 years ago

Roger Lee

131 5.38k 5.44k

What fuel are you using?

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

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Re: Fuel in oil

by Keith Wall » 7 years ago

Keith Wall

11 16 29

91 octane auto fuel, no ethanol.

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Re: Fuel in oil

by Roger Lee » 7 years ago

Roger Lee

131 5.38k 5.44k

That's what I thought. My guess is you got some diesel fuel in with the gas at the station. Usually happens when the tank truck driver doesn't flush his hose. You'd never notice in a car and most never notice in our 912, but some times it seeps or contaminates the oil and the oil level in the tank actually rises and like you if you have it tested it shows fuel in the oil. Since most people never know it just gets burned through the system in the regular gas or drained during the oil change. If you want you can just do an oil change.

p.s.
Nothing to prevent it from happening again.

Roger Lee
LSRM-A & Rotax Instructor & Rotax IRC
Tucson, AZ Ryan Airfield (KRYN)
520-349-7056 Cell

Report

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