Flywheel housing gasket replacement

[Rawze]

(01-10-2018 )Hammerhead Wrote:  ...

So I found a mystery O-ring in the oil cavity at the back of the block pushed partially into the drivers side oil rifle! Talk about feeling jitters! It's clearly been in there for quite a while as it was hardened solid. I have used Baldwin filters for several years and wonder if this is one of the O-rings from the infamous shitty batch of Fleetguard oil filters that were famously coming loose and plugging up piston cooling jet nozzles and taking out motors. I pulled an O-ring out of a Baldwin filter sitting in the waste filter bin, and sure enough I can ply it to match the inner dia of this O-ring. I have no idea what F/G uses now, but the Baldwin filter O-ring is easily twice as thick as this one, so I'm still not 100% sure, but I am 110% sure damn happy I found it when I did! There were wear marks from the machined edges of the oil rifle, and this O-ring would certainly have broken in a matter of time and I'm sure cost me a lot of sadness & money.
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I have seen a lot of engines with melted pistons due to that mystery o-ring. It is a good thing you found it before it broke apart and took out a piston.

I have always used fleetguard filters because of this. They replaced the filter design where that o-ring resides into a full-on gasket with flaps to prevent this very thing.

Other manufacturers put thicker o-rings like the one you pointed out there in that filter... not sure if I trust it though, so that is why I only use the more expensive fleece-guard now.