912 oil leak from fuel pump

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912 oil leak from fuel pump

Postby gzt » Wed Dec 22, 2010 5:02 am

I have 1100 hrs on my 912 ULS. Until recently the engine ran OK. After replacing the prop and an initial pitch setting the ground max rpm went up to 5700. Shortly after the first take-off I started to smell oil mist.
The oil pressure never exceeded 70 psi and high (?) rpms were for quite short time. Since than we changed the pitch and engine rpms dropped to about 5300 rpms. Unfortunately the fuel pump leaks oil. We replaced a fuel pump with a new one and leak still exisits. Oil pressure (with a new sender) does not show any excessive pressure during an operating regime.

Anybody got this kind of problem ?
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Re: 912 oil leak from fuel pump

Postby alan » Wed Dec 29, 2010 3:41 pm


I'm assuming your oil leak if from around the oil pump gasket. Have you carefully checked the gasket area on the gearbox? You might have a crack or warp now from the over red line operation. The only oil that could come from the fuel pump is out of the gearbox and that should only be low pressure oil carried up by the gears. Did you have your gearbox inspected at 750 hrs as recommended by Rotax?

Good luck,

If I had known I would live this long I would have taken better care of myself.
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