Friends SR20DET crankshaft has play.

[StryfeS13]

We're rebuilding my friends S13 SR20, because it has a bad rod. We got the crank resurfaced, and the machine shop told us we needed "20" for the mains, and "10" for the rods. So we bought grade 2 for the crankshaft bearings and grade 1 for the rod bearings? Is that correct?

Anyway, his crank has up and down play, like you can wiggle it up and down, but it doesnt have any side to side play.

[1KleenS13]

Did you get oversized bearings? I never heard of "grade" 1 or 2 for bearing sizes. Sounds like it may need to be align honed.

[moso]

your main bearings are most likely the wrong size. the factory uses grade to determine size when the engine was first built. there should be a size stamped on the block by one of the tabs one the rear where the oil pan mates up, use that number and the size of the crank to determine bearing size. originally the crank had bearing size numbers stamped on it and you could just use those numbers and the block numbers, but because you had your crank milled they are wrong now. you need to mic the crank and call someone who deals in sr parts that can help you like the guys at jim wolf tech. or find the chart that shows the sizes.

PS the rods have numbers too!!