RacerTim

I put the crank in about 11 last night, and went out there this morning to see how it was. Is it supposed to be a little difficult to get to rotate? I had to put a wrench in it and jerk it free, then I was able to move it back and forth with it. How loose is the crank supposed to be right after install? I definately cant rotate it with just my hands, but its not very hard to move with a wrench in it. And yes, I do have everything torqed down correctly and all the clearances measured. I am also using a Redline assembly lube.

EddieP

If the rods/pistons are not installed yet, the crank should spin freely with no effort (after all 8 rods and pistons are bolted in, it becomes pretty hard to spin the assembly).

RacerTim

No the pistons are not in yet, only the crank. What else could be holding it up? It had a slight nick in it that I thought was holding it up, so I took it back to the machine shop and they re-polished it for me. So I installed it last night again. I switched to studs, do you think I should try torqing it down with the factory bolts or something? Its a GM ZZ4 crank by the way.

EddieP

Studs will definitely change the way the main caps clamp down onto the block! If you're switching from bolts to studs, you really need to have an align hone done to the block ... otherwise, the clearances will be out of wack (I think the side to side clearance closes up, and the top/bottom bearing clearance opens up?).

WS Sick

Did you check clearances or did you just bolt it together with propper bearings?

I did a comparrisson when I built my freinds 355 last month. we measure clearnace with studs and with factory bolts and the clearance was only slightly effected , but effected none the less. If its hard to turn I would definately check clearance. Its also a good idead to smack the crank with a rubber mallet back and forth once after torqueing.

RacerTim

Yea I definately had to knock it free right after I torqued it down. Actually smashed my between part of the block and crank doing it. Would you agree that if I cant move it with just my hands its probably too tight?

EddieP

YES! There is a problem - like I said before, without the rods/pistons in place, you should be able to spin it with no resistance!

WS Sick

Eddie is right, figure out what the clearance is now measure in a few spots and in different places on the same journal. Then if its round and simply too tight have them polish the crank slightly to give you the needed clearance. If its .010 too tight move up bearing sizes.

Also Mic the crank out and make sure its what its supposed to be.

RacerTim

Just checked it all again, everything spot on where they should be. Maybe I'm just a ***** and cant turn it? I need to find a big enough mic to measure the crank. Any other ideas?

1racerdude

Loosen your caps one by one and see which one let's it turn free.If it is the rear then with the cap finger tight smack the crank with a dead blow hammer(leave no marks)On one end then the other and torque it back down.You need to smack it good.If it's one of the other four find out which one by untorking,turn and retorque until you find the one.You need .0025 brg clearance and .006-.008 end play.

It ought to spin like a **** on a s*** house door.

IrocSS85

Id say either the bearing clearance it too tight, or your crank might be bent. the machine shop can check that pretty easily. the best way to check brg. clearnce is to install the caps and bearings w/o the crank. then measure the inside diameter of the bearing's and mic the crank subtract the crank diam. frolm the inner diam. of the bearing. did you poss. mix up the main caps? I always mark them before taking them apart. #1 and #5 are obvious, but 2,3,and 4 look the same.

it should turn easily by hand. infact, you should be able to spin it so that when you let go, it keeps goin for half a rev. or so. know what I mean? have you double checked that the bearings are the proper ones? maybe they are undersize bearings on a std. crank journal? you would figure that out if you meas. brg. clearance as I suggested.
good luck
chris

RacerTim

The crank is a factory GM ZZ4 crank, I told them I need bearings for a factory LT1, correct? The caps were marked before they were removed, and as far as it being bent, wouldn't the machine shop have recognized that when they balanced all of it? I had all the components balanced together.

IrocSS85

do you have a micrometer? if you do, measure the rear main bearin. mine measured .0092. see it ifs close to that. what bearings do you have? I have the Hseries clevite's. they have room for a bigger fillet radius then the standard pseries. if you have p-series, I wonder if the zz4 crank has the lard fillet's like my eagle crank does. the bigger fillets are for more strength, and I know GM sees the zz4 crank as a high perf. crank. Id check into that. and, just to make sure you know what Im talking about, a fillet radius is the corner of the bearing surface on the crank, where it makes the transistion from flat bearing surface, to the crank throws.

I would think they would check for straightness, but Im not sure it has to be done during a balance job.