hey guys i need some help, i need to get some new main and rod bearings, but dont know exactly how to get thesizes.

i did a search and theres a how to thread on it but its not very detailed.

any help is appreciated.
thanks
-Matt

There are numbers stamped in the bottom of the block and on the side of the crank. The block has 5 numbers for the main bearings and the crank has 5 numbers for the main bearings and 4 numbers for the rod bearings. Let's say you have:

Block:
12121

Crank:
11111
1211

You add the 5 digits from the block and the 5 digits from the crank for your main bearing grades. In my example you would need 2,3,2,3,2. Then the 4 numbers from the crank are the actual grades 1,2,1,1.

There's also the micrometer method where you measure everything to determine which bearings you need. Whatever you do, double check with plastigauge. Here's the FSM. Bearing grades begin on page 53:

http://www.nicoclub.com/FSM/G20/1996_G20/1996_G20/em.pdf

Thanks for the info, really appreciate it:biggthump

Im using a different crank from another block to go into the good block. Basically using a good crank and good block. I do the same withe the journal numbers as i would if the crank and block came together right. Example:

01221
23121 equals
24342.

also had machine shop polish the journals on the crank and mic them. should i use the mic numbers to re-grade the crank. just asking fellow builders there thoughts. I don't want to spin another bearing for a good while. actually enjoying the NX would be nice for a change.

example numbers on crank say
23121
1121

but after micing the crank the corisponding grades would now be
33232
1222

I read somewhere on the forum that nissan setup bearing clearances to help cool the motor evenly. being im on a budget i really don't want to buy a bunch of different grades to puzzle piece it all together but in the end that might be the best way to do it. Hope some people with more knowledge than me can help a brother out :)

In the EM section posted above, it has all of the measurements for the different grades and stuff. If you've already mic'ed the crank, just mic the rods and mains to figure out what bearings would give you the clearance you want.

thanks swiss. got the fsm on the coffee table. i'm gonna go with the mic'd nmbers and order bearings that way. should be a lil tighter but not too tight. and will double check with plasti guage. hope to have it by next se-r meet