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Discussion Starter #1
Restoring a 1948 Model B Styled John Deere. Crank was polished and bearings fitted in the shop. The mains in a Deere are mounted on cast iron pieces that bolt to the block. I have not started the engine yet.

Here is the problem that I need to fix. When everything is in and bolted up tight, the crank has no end play or up and down play. The Deere book says that there should be 3 degrees of up and down and 5 degrees of in and out.

Here is what I think about my tractor. Maybe when the machine shop sized the mains, they were just a little off with respect to the block. Again, the machine shop didn’t have the block to use as reference.

After getting it all together, I noticed that there was not any play in the crank at all and it was difficult to turn using the fly wheel. Really hard even with no spark plugs in the cylinders. However, when I unbolted the left main bearing housing from the block, still leaving the bearings tight, leaving the housing where the inside lip is in the block, the crank is easy to turn. It has both up and down and in and out play.

The Deere book I have tells me how to figure the end play but not how to adjust it.

I'm thinking to get the up and down play, I have to add shims to the mains and to get in and out play, I have to slide the fly wheel in or out using the nut that holds it on. Again, that is not specific in the book. I guess one has to of done it before to really know.

What I don't see where there is any tilt adjustments to the mains. If that is what I need.

So, my question is: What should I do to have the correct amount of play in the crank? I would really like the cheaper suggestions since I already have a bunch of machine work done. Should I just add another shim to the main?
 

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Discussion Starter #2
The answer is: The order of things.

Not in the book but it seems, and logically so, that the main bearing mount must be bolted to the crank housing first before the main bearing are tightened up. If done the other way, there is a chance the bearing is miss aligned.

I would be the one to do it the wrong way. Because of it, it cost me a week of assembly.
Things work real smooooothly at this point. Lets see what else I can discover. I guess that is what they call learning.
 

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Anytime the mains are changed you should check the clearance using "Plastiguage". It is possible for the machine shop to make a mistake. I'm glad to hear you got your problem solved, but "Plastiguage" is still a good idea.
 
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