Husqvarna 450 rebuild, issue with crank bearing and seal.

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I am doing a complete teardown and rebuild of a Husqvarna 450 chainsaw. Although I did not do the initial disassembly I see some evidence that the clutch side crank bearing has begun to spin in its bore and therefore the clutch side crank seal is destroyed. I am wondering if there is a good method to ensure the crank bearings cannot rotate or have any slop once this is reassembled. I went ahead and used a fine chisel and knurled the surface. Any other tips, like loctite or any kind of spline cement?

Also if you look at the photo of the crankcase I believe there is a hairline fracture crack near the upper left cylinder bolt hole as reflected in the photo.
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That thing is done. You can replace the plastic cases but they're $110 and likely not worth effort. (case p/n 537 438 201)
 
That housing crack is a challenge I would consider accepting. Can you fashion a metal strap to fit on the backside to bear on the plastic and keep it from flexing? I Googled "gluing chainsaw plastic" ... If the backside of the housing has webbing that will not allow a strap to be fitted, then consider building up the area with extra plastic such as suggested here https://www.arboristsite.com/threads/glue-for-stihl-plastic.229292/

Googling "spun crankshaft bearing in chainsaw" yielded an interesting result ... https://www.arboristsite.com/threads/046-spun-bearing-on-crank-clutch-side.131844/ OP didn't post a follow up to declare success or failure, so I suspect they didn't finish. In their situation, there was a loose fit between the crankshaft and inner bearing race. Googling "Locktite bearing retainer" yields https://www.henkel-adhesives.com/us/en/products/industrial-adhesives/retaining-compounds.html offering ways to secure bearings in housings.

Allow the saw to fully warm up before cutting and avoid high revs without a load.
 
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I dimpled the cylinder, and I never thought of loctite 660. I think that will work.

Top end is nice so, and it does not have oem bar or chain. So I would bet someone overtightened the chain and ran it like that for years.
 
I dimpled the cylinder, and I never thought of loctite 660. I think that will work.
What's on the underside of the housing? You don't want the crack advancing any further. Is plastic welding the underside a possibility?
 
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What's on the underside of the housing? You don't want the crack advancing any further. Is plastic welding the underside a possibility?
It is a very very thick plastic. I plan to put a little moto seal on the crack but the plastic is not brittle at all I may drill stop it and dremal it smooth.
 
It is a very very thick plastic. I plan to put a little moto seal on the crack but the plastic is not brittle at all I may drill stop it and dremal it smooth.

I think you're on the right track.

It's your own project to tinker with. If you were repairing it for a paying customer, I'd tell them to scrap it.
 
Red loctite will do the job of locking bearings in place. You don't have to spend a fortune on it.

I'm not sure I'd use that plastic case though. Amazon has an aftermarket one for $48 and Ebay for $40. A good used one is also $40.
 
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Good point. Let me check the used option. I have a little budget left. As I'm already this far for a good saw.
 
This one seems to have a crack too?

Hard to tell if that is a crack or a molding blemish.

This one looks decent:
 
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I decided to use Moto seal across that surface after I dremeled a Groove in the crack and then made sure the Moto seal got down in there with a brush then on the opposing side of the cylinder used Loctite on the metal surfaces to keep the bearings from rotating.

Gunna let it all dry 24 hrs and give it a test. Should make a great spare saw as it won't be used heavy duty. I can always replace the plastic later on if it cracks more.
 
It will probably work just fine. I would have assembled right away, once applying the sealant. It may also be possible to scuff up the outside and apply conventional JB weld.

What's the outside of that area look like?
 
I did assemble right away. Just enough time to snap the photo. I prepped the cylinder first, then raced to brush it on the plastic side and whammed it together. It oozed out after I tightened it so that's good. And there are no external cracks at all on the opposite side.
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