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Question on Crankshaft Main Bearing

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Doing a rebuild on a 1980 DT175.  Cases are split and I tried to install a new main bearing after putting it in the freezer overnight then heating the case with a torch.  The bearing went in half way and I hit it all the way in with a rubber mallet.  It moves fine but is dry.  If it moves OK when I lube it, is it OK?  Should I have put lube on before installing it?  What lube should I use?

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I've used regular 10w-40 for lube. Any kinda oil is fine really. 

As long as the bearing is square in the hole and doesn't bind, spins smoothly, and makes no noise, you should be okay.

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I just drizzle yamalube on them after install. Once the crank is in and the cases are together, you'll know if its not square. But that is fixable.

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3 minutes ago, 2 STOKE YZ DOC said:

I just drizzle yamalube on them after install. Once the crank is in and the cases are together, you'll know if its not square. But that is fixable.

How would I know if it is not square when the crank is in and then how would I fix it?

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3 hours ago, molloyjp said:

How would I know if it is not square when the crank is in and then how would I fix it?

Crank will not rotate easy and bind. You should be able to see if they are square looking from both sides of bearing. You can get away with pulling crank in from one side and the other to square (but realy easy when doing so, not ape) with heat on case where bearing journals are. 

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