Oh crap, think I wrecked this case?

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2-StrokeDude

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Working on an MS 361, I had a friend help me try to put the bearing in for the clutch side engine case, long story short, we didn’t have it hot enough, and he tried hammering the bearing in a little bit. We managed to get it out since it wasn’t hot enough, but wrecked the new bearing. That part I’m not worried about, it’s the case. Because it wasn’t hot enough, it kind of dug a little bit into the case, and made just a little bit of a groove, you can feel it with your fingernail but it’s not insanely bad, I think it’s going to be OK? It’s not deep grooves that are going across that I would think would cause an air leak, do you think this is OK? I sanded it down lightly a little bit with a piece of 200 grit sandpaper to kind of help get rid of any burrs, think this case is OK to run or will I have an air leak?
 

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There are retaining compounds that might help if you're concerned it won't seal. It's the outer edge where the seal presses in you need to be worried about the surfaces being good enough to not leak. Retrospectively you could possibly put some whicking anaerobic sealant between the seal & the case if it leaks.
As mentioned, well heated case & frozen bearings are the way to go
 
Well I put the case in the oven today at 400° and it actually was enough to get the bearing in place. Seems like it’s seated in really well so I am not thinking I’ll have issues with it sealing.

I Got the cases and the crank all put back together today, went to install the crank seal on the clutch side, and it looks like the seal is a little pushed out? Should that rubber lip be like that?
 

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Well I put the case in the oven today at 400° and it actually was enough to get the bearing in place. Seems like it’s seated in really well so I am not thinking I’ll have issues with it sealing.

I Got the cases and the crank all put back together today, went to install the crank seal on the clutch side, and it looks like the seal is a little pushed out? Should that rubber lip be like that?
Hate to say this but no. That seal is toast.
 
Hate to say this but no. That seal is toast.
Ok, well good thing the kit I bought with a bunch of gaskets and stuff came with an extra seal. Any tips on how to make sure that doesn’t happen again?

I don’t have any deep sockets that are tall enough to hammer the seal in all the way, so I just used a piece of 3/4” PVC pipe. When I was installing the seal and I pushed it down on the crankshaft, it did not come out like that but after I hammered it down into the saw it that started happening.

Also after getting the cases all bolted up and making sure the crank is centered in the case, there’s a bit of resistance when trying to turn the crank, and it is not moving that freely. I know it’s centered correctly in the case, is this just normal on a saw that hasn’t been run yet?
 
The inner lip of the seal needs to go over the step on the crankshaft. Stihl makes a special tool for this but if your careful you can “work it” over the step with a small flat blade screwdriver. Kinda hard to explain but I hope that makes sense. Do a search on YouTube I know there’s a few videos showing how to do it.
 
You can wrap a thin piece of plactic or aluminium from a can around the shaft. A couple of wraps of tape would probably work too.
If you use aluminium be careful to rotate the seal onto the shaft over the aluminium in a way that it doesn't slice the lip of the seal with the sharp edge of the aluminium
 
Even a piece of a sturdy breadbag over the crank end. Grease the plastic and the seal lip.. get the seal over the ramp,pull out the bag gently, voila. No damage. Most of the time..
 
I used a file folder piece of plastic to in stall the seal.
View attachment 1134532View attachment 1134533View attachment 1134534


I tried out your trick and it worked! I had to take a dull very small flathead screwdriver and carefully push around the seal a little bit, since the lip was still trying to push out. When I carefully pushed at the seal with the screwdriver it kinda popped into that groove in the crank. Seems like that did the trick! How does this look?

Also, there’s a groove in the crankshaft is that where the seal is supposed to land in? I think that is where that lip is now, pretty sure that’s where it’s got to seal up.

Ive put crank seals in mopeds and stuff before, but they are different than chainsaws, never had to work on one this extensively before
 

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Also, there’s a groove in the crankshaft is that where the seal is supposed to land in? I think that is where that lip is now, pretty sure that’s where it’s got to seal up.
Nope. That's where the retaining ring goes. You have to go deeper 😳 with the seal. At least flush with the bearing. Probably a bit more. Somebody with mor 361 knowledge should know for sure.
Also after getting the cases all bolted up and making sure the crank is centered in the case, there’s a bit of resistance when trying to turn the crank, and it is not moving that freely. I know it’s centered correctly in the case, is this just normal on a saw that hasn’t been run yet?
A bit of resistance is normal. The pressure of seals on the crankshaft slows it a bit.
 
I just watched the video, and I can not figure out why he did not use the sealer on both sides of the gasket? There were a couple of comments asking the same with no replys?
I said the same thing. then I realized he was just using it to hold the gasket in place while he lined everything up. I just left it dry.
 
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