: Rebuild bearings



dgarrett
05-17-05, 11:05 AM
Hello, I am new to this thread and have been looking for info on rebuilding N* engines. All the posts I have read say there is no over sized engine bearings and that only GM sell the stock ones for alot of $.

I found these on the web, does any one have experience in dealing with these?

http://www.rockauto.com/catalog/catalog.php?carcode=1361382&parttype=5220

http://www.carparts.com/cgi-bin/sewse?/u/www/webepc.com/cmm/scripts/epc20.cmm+jcw-carparts

Thanks!

zonie77
05-17-05, 12:07 PM
Rock auto is ok, have had good service from them.

dkozloski
05-17-05, 01:13 PM
The reason there are no undersize bearings is that the crank has rolled fillets that cannot be reground without seriously weakening it. The only way your cank would require regrinding anyway is if there were some kind of disaster involving oil contamination or lubrication failure. If you find an automotive machine shop that wants to grind the crank, ask them how they plan to reroll the fillets. If they say it's not required get the hell out of there.

Spyder
05-17-05, 01:17 PM
The bearings on both of those websites are from the same manufacturer...Both are Sealed Power, so if you decide to go for it, use RockAuto...20 bucks cheaper. But keep in mind dkoz's comments on the rolled fillets...Search other posts for this, as there is quite a bit of info...

dgarrett
05-17-05, 01:43 PM
So, If I had a good crank from a differnet engine, I could just use it with thicker bearings and aline bore the case/block? are the rolled fillits on the main bearing suffaces or on the Rod journal surfaces as well?

dkozloski
05-17-05, 02:13 PM
With a replacement crank new/used use std. size bearing inserts. There is nothing to align bore. Both rods and mains have rolled fillets.

Concourson20s
05-17-05, 04:50 PM
I have understood that there are only rod bearings available in both over and undersized. As for main got to stick to std. However if damage exists to the main bearings, take the engine to the recycling plant and get an offer. It's junk regardless. But true you won't need any kind of differance in bearing size unless there was a problem with lubrication, or extremely high mileage. And personally I don't really like regrounding cranks, if that happens i just go find a low milage shortblock and rebuild that. I'm going to be rebuilding my northstar very soon. I got my engine and a spare, I'm going to plastigage both and keep the better example, going with all new main/rod bearings, piston rings, pins, ect. I currently consume some coolant, about 3 cups in a month (just enough to trigger the IPC). Although I'm almost certain it's the gasket, to be safe i got this other northstar dirt cheap, just incase my head is cracked. I'll be posting pics of the whole tear down, and comparisons of the parts ect.