Oil leak at the screen housing

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dcannon
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Name: Dan Cannon
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Re: Oil leak at the screen housing

Post by dcannon »

New oil screen/nut (minus the screen) and installed the crush washer "backwards" so that seem is against brass. Leak gone thank you all for the ideas. Since I changed two variables I can't be sure if one or both was the answer.
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8413
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Re: Oil leak at the screen housing

Post by 8413 »

I figure the seam side of the crush washer is more able to conform to irregularities in the mating surfaces. So maybe those of us having better luck installing the seam backwards have an irregularity on the screen that the seam of the crush washer is forming to better than the smooth side? Seems to me that if both mating surfaces are perfect (screen and housing), the orientation of the crush washer wouldn't matter as far as leaks are concerned.
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asheli
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Re: Oil leak at the screen housing

Post by asheli »

Is there a seal between the Temp bulb and the adapter ? And I think there is a crush washer between the adapter and the screen cap but I don't know the P/N
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6643
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Re: Oil leak at the screen housing

Post by 6643 »

asheli wrote: Wed Jul 31, 2024 12:26 pmI think there is a crush washer between the adapter and the screen cap but I don't know the P/N
AN900-10, IIRC (MS35769-11)
Is there a seal between the Temp bulb and the adapter ?
There is either a flat flange that is clamped between the adapter and the temp sender nut, the early style, or the sensor bulb is tapered and fits a matching taper in the adapter.

There's a Neal Wright article on the subject: viewtopic.php?f=10&t=107
5836
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Re: Oil leak at the screen housing

Post by 5836 »

Re: Oil Drip from screen housing.

I had the same problem a few years ago. I changed the crush washer a few times.
In the end, the problem was a damaged "circular flair/lip" at the end of the temp probe. This was due to years of removal & reinstall.
The drip would start at the smaller fitting for the temp probe and get blown down to the bottom of the hosing by the suction air exiting the lower cowl. I ordered a new temp probe / installed and the drip stopped.

Br,
Mike
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