Thread: crankshaft fits "tight"

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i just installed the crank in my 350. torqed it down 70. when i tried spinning it it didn't move freely. bought the crank at autozone . the guy at the machine shop said their cranks are not machined to the best quality, and the journals may not all be the same size. he also said the journal caps go in a certain order from front to back, how can you tell. this is not the same shop where i had the block done, they didn't do it right. should i take the crank back or have this machine shop check out the block and crank. thanks for any help!!

Oh, my, my, my.
The crank is probably ok, the main caps might be out of order.
I usually mark my crank, and rod caps before I take them out. If the block was line bored, the machining makes the order critical for clearance.
Since there are only four caps, you might try plastiguage and try to recapture the cap order.
The front and rear caps are pretty obvious, but the two inbetween might have been switched.
If the crank is suspect, plastiguage will show the crush on each journal.

Originally posted by littletruckin
i just installed the crank in my 350. torqed it down 70. when i tried spinning it it didn't move freely. bought the crank at autozone . the guy at the machine shop said their cranks are not machined to the best quality, and the journals may not all be the same size. he also said the journal caps go in a certain order from front to back, how can you tell. this is not the same shop where i had the block done, they didn't do it right. should i take the crank back or have this machine shop check out the block and crank. thanks for any help!!

THE CAPS SHOULD HAVE BEEN NUMBERED WHEN THE ENGINE WAS TAKEN APART.DID YOU MIC. THE CRANK?IF YOU DID WHAT SIZE WAS IT?WHAT SIZE ARE THE BEARINGS?

Good point Erik. Are you thinking oversized bearings and not undersized crank?

IF IT WHERE MY ENGINE I WOULD LOOK THE LINE BETWEEN THE CAP AND THE BLOCK WHEN THE CAPS ARE TORQUED IN PLACE.SOMETIMES YOU CAN SEE A FEW THAT DON'T LINE UP.DO YOU OWN IN-SIDE BORE GAUGE?MAYBE THE CAPS WHERE SWITCHED WITH ANOTHER ENGINE.IF IN DOUBT HAVE IT LINE HONED,OR BORED.

Originally posted by dcoffield
Good point Erik. Are you thinking oversized bearings and not undersized crank?

YES,I HAVE SEEN IT HAPPEN BEFORE.

the machine shop where i had the line honed didn't numbern the caps when he did it, also didn't bore the block to my specs. thats why i got a new machinest. i didn't mic it, but got the crank and bearings as a kit. thinking of haveing new machinest recheck everything, said he'd do it for 25 bucks

Originally posted by littletruckin
the machine shop where i had the line honed didn't numbern the caps when he did it, also didn't bore the block to my specs. thats why i got a new machinest. i didn't mic it, but got the crank and bearings as a kit. thinking of haveing new machinest recheck everything, said he'd do it for 25 bucks

THE BLOCK SHOULD BE BORED TO THE PISTON MAKERS SPECS.

i wanted the block bored for a set of .030 oversized pistons but he screwed up and only bored it 20 over. i didn't want to waste more money to have it done again so i lost intrest in motor for about a year.

Originally posted by littletruckin
i wanted the block bored for a set of .030 oversized pistons but he screwed up and only bored it 20 over. i didn't want to waste more money to have it done again so i lost intrest in motor for about a year.

.020 OVER.ARE YOU KIDDING?

i wish, thats why i changed machinest. the old one didn't even do the work at the shop, took it home or something i think, then over charged me. pissed me off. the guy i got now has a better shop, seen it in person this time.

Originally posted by erik erikson
.020 OVER.ARE YOU KIDDING?

THE REASON I ASKED THIS WAS A CAST,HYPEREUTECTIC, AND A FORGED PISTON ALL REQUIRE DIFFERNT SKIRT CLEARANCE'S.AND IT ALSO VARY'S FROM MAKER TO MAKER AND IT ALSO DEPENDS ON YOUR APPLICATION.

i plan on putting the engine in a full-size or my s-10. i want to build it for low end torque. it will be mostly stock except for cam, pistons, and a demon carb.

littletruckin, you make it sound like your first guy bored the block without having the pistons on hand. That ain't the way it's done. Any self-respecting shop will not cut the block until they have the pistons in the shop with the block to bore and hone the block to the correct size and the correct piston-to-wall clearance for the pistons being used.

pistons were ordered last week so the new guy can check everything out includeing the crank. my brother has used this guy for years. hope he works out for me too.