BBC Broken Rear Main Cap Question???
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From: Austin, Texas
Car: 1983 T/A
Engine: 454 BBC
Transmission: Built 700R4
Axle/Gears: Weak 10 Bolt/3.23
BBC Broken Rear Main Cap Question???
So while recently replacing my oil pan gasket, I was inspecting my crank when I found that my rear main cap has a broken corner exposing the oil pump shaft. I purchased a set of caps to replace the broken one. A buddy of mine suggested that I needed to take my block to the machine shop and have it line honed if I was going to replace the cap or else I would get uneven bearing wear on the new bearing. Here is my question, If I replace all of the bearings, will I still need to get the thing honed or not. I figure there has to be someone out there with some machining experience. I'd rather have a second opinion before tearing the thing apart. Thanks!!!
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
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Re: BBC Broken Rear Main Cap Question???
Absolutely you need machine work if you're replacing caps.
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From: Orlando
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From: 51°N 114°W, 3500'
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Re: BBC Broken Rear Main Cap Question???
The only way to ensure the new main cap is true to the webbing and inline with the others is to have the block line honed. If you don't get the machine work done, you'll toast the bearing and cause more damage than the machine work will cost.
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May 10, 2023 07:19 PM




There really isnt any debate on this. It 100% has to be done. 
