main bearing/crankshaft

Check for adequate clearance around the outer diameter of the thrust bearing. I just put one together recently with clevite bearings and I had to grind some material off the outer edge of the thrust bearing because the relief in the block was not large enough. I found the problem when I torqued the mains and the crank would barely turn by hand.
 
bigc19 said:
Im hoping nothings damaged as well. After looking back at what I ordered, theres no indication that the studs are 14mm, so its safe to say theyre 12mm. Im still a little lost on the torque. My instructions that came with the kit say 175, arp website says the same, but it seems all yall who have done this before are running 125. As for if the caps are correct, I honestly am not sure. The fsm says that they should be in order, 1-7, but mine has 2 6s and 2 3s. I think they may have been more random originally. I would assume the only way to put them where they need to be is to plasigage them all? Or could I just torque them one at a time and as long as it spins freely, theyre fine?
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You should be looking at the stamped numbers on the side of the cap and not the cast in numbers on the front side of the cap.

When you removed the old bearings did you check to make sure they were STD size?
 
Thank you 94 12valve. I had my FSM open to the page showing that the whole time, and somehow completely spaced on that. The caps are 100% in the correct way now. Old bearings are definitely STD in size. Now I just dont know what to torque to. As said, the instructions on the studs call for 175ftlbs, but to all you that are helping me, thats 50ftlbs high. Anyone have insight on what to do for that?
 
As an update again, Ive began torquing them down and its been spinning smoothly. Im going to stop at 125 until I get more replies on what I should stop at, 175, or 125. How many bearings should I plastigage? Should I just be safe and do them all one at a time, or, with it being std to std bearings and the crank only being polished, could I get away with doing, say, #2 and #5?
 
And as a correction, they are 14mm mains. With that being found out, I would say its safe to assume 175ftlbs is correct
 
I was going to do that, but couldnt find the caliper. I looked where I ordered them from and they are indeed 14
 
I know you figured it out, but you can use a wrench to check bolt sizes. If a 14mm open end wrench fits over the threads, it's 14mm.
 
Plastiguage all 7.... all the way across.... then do all 6 rods..... write it all down. Do it once do it right. :Cheer:

And go to 175 on the 14mm mains.
 
I bet between putting the main studs in, new bearings, and polish that your clearances are too tight. I know your talking about mains, but I have seen on rods as much as .004" difference between stock bolts and a set of good bolts. They make a big difference
 
If your using a 9/16" socket you have 12mm studs 125 ft/lbs 14mm should be a 5/8" socket 175 ft/lbs.

If I were you I would check all the mains, rods, and check you thrust just to make sure its all right.
 
I will definitely check all the bearings today.

Lewis6030, could you explain howd they would be too tight? I would think, if anything itd be a little loose. The bearings are the same size as stock, the crank would, I would think, be slightly smaller in diameter. The biggest difference would be the extra 46ftlbs of torque holding the caps. Just want to understand what you mean
 
The bore alignment should have been checked at the shop.

When you assemble it. Put the caps in place and torque them one at a time in steps. IE.... take them all to 50, then 75, and so on. But check crank rotation after raising the torque of each cap. That way if there is an issue, it shows up early before you phuck something up.

My14mms are torqued to 175lbs. But, I checked it with plasti-gauge at 135lbs and at 175lbs just to make sure there is not a problem developing.

btw... it blows me away that you're building an engine and you don't know where your caliper is. I'm just finishing up an engine and can tell you just about what every clearance in the engine is. That the proper way to do it. Just opening the boxes and bolting the parts together, is not a good idea.
 
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Youre absolutely right. This is my first time doing this, and I guess I need to just slow down. I definitely dont want it to fail when I get it back in the truck. I had planned to checking everything as I went, but am a month behind where I wanted to be, and started rushing. Definitely dont need to be rushing with this
 
If your block was line bored with factory main bolts at the machine shop, then afterward you put in the studs the clearance will be less than with stock bolts because of the studs having so much more clamping force.
 
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