help with crank

[86mustang5.oh]

i need to get my crank down i am having my friend do it for me hes in a machining class i need it 20 over not i need to know how big the crank its that the bearing go around on the mains and the rods if anyone can point me there i have a mustang book and it says chit about it.

 

[Rick 91GT]

Well if your buddy is a machiniest he needs to measure the crank, then determine how much needs to come off then turn it on a crank grinder.

FWIW the stock journals are 2.249", .020" over on a stock crank is a lot.

 

[TheUser]

My stock crank has R 010 and M 010 stamped into it, probably from the previous rebuild. That probably explains the main bearings being -.010 right?

I took it to the machine shop and got it polished and they said it's now "20 20", so I guess that means it's .020 over, so now I'll need main bearings -.020, correct?

I had to buy a differn't block and I didn't take my old main brearings out of the other one (I let the machine shop keep it), so I can't measure clearances on them.

So far, the rod bearings I've measured have been coming out to .003 w/ plastigauge. The used bearings are .010. I thought I read somewhere .003 is the most clearance allowable, but my haynes says .0024 max. What size should I get now? I'm gonna check them all again to make sure.

 

[TheUser]

I'm gonna go check them all again to make sure.

BUMP!:SNSign:

 

[Rick 91GT]

.003 is a lot on the rods, what is the side clearance? What is the main clearance coming out to be.

Yes your crank and rods are now .020" UNDERSIZE

what oil pump did you plan to run?