Read main bearing cap thrust Babbitt thickness

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Dave1
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Read main bearing cap thrust Babbitt thickness

Post by Dave1 » Wed Dec 13, 2023 1:50 pm

What is the best thickness for the Babbitt on the thrust faces on the rear main cap?
Making a set of bearing caps to accommodate a Chevy crankshaft.
Let’s just say that some of my calculations were wrong, and the cap is a bit undersize in the length direction. Wondering how thick the Babbitt can be finished before it will cause problems?

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JTT3
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Re: Read main bearing cap thrust Babbitt thickness

Post by JTT3 » Wed Dec 13, 2023 2:16 pm

Were you thinking thickness on the interior block side or the transmission side for the Chevy crank, just curious?


Dan Hatch
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Re: Read main bearing cap thrust Babbitt thickness

Post by Dan Hatch » Wed Dec 13, 2023 2:36 pm

I think I have set of Chevy main bearing caps I would part with. Email me. Dan


Kerry
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Re: Read main bearing cap thrust Babbitt thickness

Post by Kerry » Wed Dec 13, 2023 3:27 pm

When Ford started with the T and Dodge was suppling, the cap had as much as 1/4" of babbitt on both ends. All the caps had babbitt flanges on them to run flush with the block bearing saddles. In Canadian assembled engines this was done right up into the end of the 16 model, when re-building they show no more than normal wear.


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Dave1
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Re: Read main bearing cap thrust Babbitt thickness

Post by Dave1 » Wed Dec 13, 2023 3:32 pm

I have the bearing caps made up. I had planned on having about .050 “ of Babbitt on the rear thrust surface, however it’s looking like about .150”
The final will depend on outcome of the crankshaft grind


Topic author
Dave1
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Re: Read main bearing cap thrust Babbitt thickness

Post by Dave1 » Wed Dec 13, 2023 3:34 pm

I will be using the rear main as the thrust , rather than the centre main as the Chevy crank was designed


Adam
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Re: Read main bearing cap thrust Babbitt thickness

Post by Adam » Wed Dec 13, 2023 8:08 pm

Thrust is on the front of the cap, so move the cap forward and put about .062” babbitt on the front and the rest on the back. Mill .055” of the iron “face” off the front and rear of the 3rd main saddle and cast & machine thrust in the block too. It will extend the wear life of the thrust almost 3x in theory.

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Mark Gregush
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Re: Read main bearing cap thrust Babbitt thickness

Post by Mark Gregush » Wed Dec 13, 2023 8:34 pm

You could also do a little work to the saddle and add thrust to the block.
I know the voices aren't real but damn they have some good ideas! :shock:

1925 Cut down pickup
1948 Ford F2 pickup

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