Contaminated Fuel

Re: Contaminated Fuel

by bill martin » 12 years ago

bill martin

10 757 0

Frank,

The diesel fuel goes past the rings without burning. The compression in a gasoline engine is not high enough to vaporize and ignite the diesel fuel and the spark plug will not ignite it for the same reason. It is the very high compression in a diesel engine that causes the fuel to vaporize and also heats it by compression to the point that it will burn. Thats why no spark plugs are necessary in a diesel engine. Only a glow plug for starting.

You might want to change your oil because the diesel fuel will thin it and change its viscosity. If you have changed the gasoline and run the engine for a while, the carbs are probably OK.

Bill.

Re: Contaminated Fuel

by Frank Wright » 12 years ago

Frank Wright

1 2 0

Thanks for the info Bill. We are aware of the reason the diesel fuel doesn't burn. We did an oil and filter change after the discovery of contaminated fuel, drained the fuel tanks and refilled with fresh fuel, flew a couple of hours and checked oil status. No oil growth. Since then the aircraft has flown another 120 hrs across the Australian outback and we've had no problems at all.

Re: Contaminated Fuel

by Diego Volpi » 12 years ago

Diego Volpi

0 2 0

Bill ,thank for your answer I think was for me, now it's more clear.

Yes we changed oil several time, cleened the tanks and the fuel circuit in all planes. Let me tell en other thing we learned at that time : We have a Tecnam P92 rotax 912 S2 equipped, certified plane, high wing . It was brand new, just arrived from factory when the the story of cotamination did begin. After a month in the contaminated fuel( 13% diesel) the carburators floats needles were not closing anymore. the result was: leaking intake filters and fuel into the intake manifold in the pistons trough the rings and into the oil eventually. Yes we had en increse of oil level overnight, no engine running if fuel valve was left open ( high wing few feet of pressure)
the rubber part og the Needles were partailly melt. Same things happened to other planes refuelling alwais at the same fuel station. So if you suspect diesel contamination for a period relativelly long ceck the carburators needles. Take a look to the pictures : it sais: "Needles after 130 days immersion in fuel contaminated with 13%diesel" ;but they start to leak after a month

ciao Diego

spillogalleggianteBing009.jpg (You do not have access to download this file.)

spillogalleggianteBing010.jpg (You do not have access to download this file.)