Rear Main Seal leak

SuperStock426 said

The reason it was align honed is because it was needed. It's part of the process of maintaining proper tolerances in the main caps. And when you align hone it sets the crank a few thousandths deeper into the upper mains requiring sometimes a undersized timing chain to take up the slack. That's the reason I had to go with a --5 Rollmaster timing chain. Taking a few thousandths from the main seal bridge by sanding it snugs up the loosesness left behind from the align hone.

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I'm extremely familiar with it since I've done it before working in a machine shop. Unless an engine spun a main and damaged the block, there is zero need to change the crankshaft position. Lemmie splain. The main caps are remover and slightly milled where they meet the block. Now, we have an egg shaped crankshaft main bore, but it's all on the cap side.

The block is the set up in the align hone or bore and JUST SKIMMED in the block side to barely even knock the dust off, while the main caps are trued. It does not change the crank position one iota. This is the correct way and if the shop didn't do that, what else are they doing or not doing?

That was my point. Of course, doing it "their way" certainly works, but then you're faced with an oddball timing chain.