Hint about case through bolt seals

[Ho Hum 74]

So I can now reflect on the quality of those little blue seals that are in some of the gasket kits. You know, the ones you put under the case through bolt washers: They’re crap! I had developed a leak which looked like it was from the rear of the sump plate. When I looked up there was a small trickle of oil running from the case through bolt nut. I tried to put another ¼ turn on the bolt but this didn’t work – actually it made it worse.

This weekend I went after the seal. Luckily for me it was on the nut end so I could get the nut and washer off and clean down the area. What I found was interesting: The original blue seal was mashed to a pulp. Really, there were just little pieces of it smeared under the washer. But the one on the other side seemed decent. The new ones I got from Pelican are green like the oil return tube seals. They seemed thicker and healthier. After a bit of maneuvering I got the seal in place. Seems like this was the problem.

If I were rebuilding again I would use the green seals and toss the others.

Tristan

[Tim Walsh]

Tristan,
did you put anything on the seal before you installed it? On one motor I helped with we had the same sort of problem. The fix? Replace them all, a light coat of silicone lube and hold the washer in place with a set of pliars while torqueing. It seems to have prevent the washers from spinning, crushing and breaking.

[Ho Hum 74]

Tim,

Actually we opted not to put the silicone sealer on (the black stuff) on. Just gave them a light coat of oil and did as you said: hold the washers with a spare pair of hands and pliers. Maybe this one just got crushed because it's opposite one was fine (I could see it when I pushed the bolt in to get the nut and washer off).

[ChrisBennet]

See page 3 of the thread Thru-Case Bolt O-Rings...am I OK???
Among other things it contains the famous words of John Walker:
"blue orings suck!"
-Chris

[dtw]

Silicon lube, not silicone sealer.

Tim and I had much better luck with the silicon lube than just motor oil in getting the o-rings to seat properly.

I agree, the blue ones are garbage. I will use the Viton ones next time around.

[DonE]

After reading this and related posts, why is everyone so against using the silicone sealer with the o-rings? Its works, right? I just joined my case using the black sealer WITH the blue rings....

[Ho Hum 74]

I just joined my case using the black sealer WITH the blue rings

Oh my! You are so SCREWED now. But thank goodness you realised this and now you can start again...

Just kidding. I think you're fine. The posts I read talked about the silicone causing the seals to squeeze out from under the washers and that gets messy if you snap one.

There was a monster thread that went back and forth between Wayne and someone else about this. No real conclusion, Chris Streit and I decided to go without the silicone. No big deal.

Tristan

[Bobboloo]

The only time I would consider silicone sealer is if the bolt hole was out of round which makes it difficult for on O-ring to seal. Even in that situation I think I would opt for another case to start the build with that was less distorted.