Main bearing inserts

[Brownie450]

Can the main inserts on an A be rolled in without
pulling the crank, or does the crank need to be
taken out?
Jim

 

[caterpillar guy]

If you loosen the mains some I would think you could roll them in like any other engine. Might want to see what the journals look like before rolling them in though.

 

[kshansen]

(quoted from post at 19:42:07 06/12/23) Can the main inserts on an A be rolled in without
pulling the crank, or does the crank need to be
taken out?
Jim

Very possibly you can but from my experience rebuilding my BN decades ago I might hesitate to do that.

See I did mine out of frame so to speak and due to wear on the crank had the mains and rods ground to 0.010 undersize. Then when I began reassembling the engine with new bearings once the mains were all torqued the crank was very tight to move. At first I thought the crank was the problem but it miked up perfect. After many checks determined the problem was in the alignment of the main saddles in the block.

So off the block went to the machine shop to be line bored! Once back assembled with the same bearings and crank now turned smooth and free as could be, also checked clearances with Plastigauge to be sure. I figured that in the 30 years that block had been heated and cooled thousands of times the block casting moved a little at a time to where it would not work as is.

 

[Brownie450]

Thanks guys. I rolled them in on the cub
when I did it.
Jim

 

[RedRamGT]

I think you can remove the front two main caps, but the rear cap requires the engine to be disassembled. It's been a while since I've done that, but I recall the rear cap couldn't be removed with the engine in the tractor.

 

[willysz]

I rolled them in on my 500 crawler with the c135 engine