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Discussion Starter #1
Hey guys,

first of all it has been a few years since I assembled a motor, my last was a sbf 2-3 years ago.

anyways, right now I am assembling a 327 S/J for a belair im doing. The crank is .020/.020 and i assembled w/ federal mogul assembly lube. The clearances measured out to be .0025-.0030, using micrometers and a dial bored gauge.

The caps have been numbered 1 thru 4 and were put back that way (1 starting in the front? I assume)

now w/ the crank and rear main seal installed, it seems tight to me? it takes considerable force on the rod journal to get it to turn, once its rolling you can continue rotating it fairly easily. idk if this is normal or if there is a problem else where, what is yalls thoughts.

Zach
 

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My sbf was 22 ft lb's for the assembled short block with low tension rings.............not sure how much just the crank would be but its considerably less for sure.
 

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I would remove the rear seal and see what it does first. Then if it is still tight, like someone else said loosen one at at time. I've had a crank that was slightly tweaked on a journal be hard to turn once. But to me it sounds like the seal is just locking it down a little until it gets moving. Make sure to check thrust also.
 

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What type of assembly lube do you have on the bearings?

Did you use a dial indicator and check run-out of the mains before installing the caps?
 

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Grizzly
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its should turn this easy...you put the thrust bearing in the right spot:confused: and you put the bearings tit to tit
 

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Discussion Starter #9
GT 350, is that your motor? rear seal installed? I feel it is too tight, so it most likely is.... gonna loose'n main caps and see whats up. I did spin it over w/o the main caps and it still took some effort to get it rolling, the bottom of the 2-piece rear main seal was in too, so maybe it is holding on to it?
 

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Should turn fairly easy even with the seal in place. I would pull the crank and install all of the caps with no bearings and check to make sure the caps and main saddles match perfectly. If that's good, install bearing shells in just the front and back main saddles. Drop the crank in and check the center 3 main journals for runout with an indicator. Should pretty much be zero. If that's good, reinstall all bearings in block, drop the crank in and make sure it rotates freely and quietly without the caps. If you're still good, install 1 cap at a time, just snugging the bolts, and check for free rotation. Still good, torque 1 cap at a time in the normal sequence checking that it's free after each one. That way if it does tighten up, you'll have a good idea where the problem is. The rear cap with the seal in place will tighten it up a little of course. But it still should be pretty free. Good luck.
 

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Grizzly
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GT 350, is that your motor? rear seal installed? I feel it is too tight, so it most likely is.... gonna loose'n main caps and see whats up. I did spin it over w/o the main caps and it still took some effort to get it rolling, the bottom of the 2-piece rear main seal was in too, so maybe it is holding on to it?
no but every motor i ever done turns that easy with out pistons installed..
 

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it takes considerable force on the rod
Define "considerable force" and "fairly easy.........."

should turn this easy...you put the thrust bearing in the right spot
X2. You have it on a stand? Loosen the rear cap, take a block of wood and a bar and pry the crank forward against the thrust, then re-tighten
 

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I'm not that familiar with the assembly lube you used, could be that is making it feel tight. I always use oil myself because I'm going to pre-lube it with a drill motor long before it's ever going to fire. Mine turns easy like the video shows and if you grab a counterweight and spin it, the crank can usually go a full turn with it's own momentum.

What did you set your thrust bearing clearance to and did you "square it" but tapping the crank against it?
 

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I had the same issue when I rebuilt my 65 Cadillac 429ci V8

My good friend checked over the machine work,we installed name brand main bearings / thrust bearings. Used assy lube on everything. After we torqued down the caps the crank would not spin easy by hand.

Removed crank and Rechecked everything....was all in spec.

We put the crank back in installed rods and pistons, and had to use a wrench on the fromt pully bolt to get it to rotate.

Crossed our fingers and dropped it in the car. Primed the oil pump/ system and she Fired right up and held 50psi....5 years later and 10,000 miles it still holds 50 psi at high idle and have had no issues...
 

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Discussion Starter #15
Define "considerable force" and "fairly easy.........."



X2. You have it on a stand? Loosen the rear cap, take a block of wood and a bar and pry the crank forward against the thrust, then re-tighten
- Considerable force means, to tight to rotate by hand on crank snout, gotta pull on a rod journal.

- it is on a stand too. i will try to push the crank forward.:confused:
 

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AVAST
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before you tear into it remove the rear seal and try it. sounds to me like its just stiction from the rubber. thats how seals act, they grab then once in motion they slide freely.
 

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Discussion Starter #17
I had the same issue when I rebuilt my 65 Cadillac 429ci V8

My good friend checked over the machine work,we installed name brand main bearings / thrust bearings. Used assy lube on everything. After we torqued down the caps the crank would not spin easy by hand.

Removed crank and Rechecked everything....was all in spec.

We put the crank back in installed rods and pistons, and had to use a wrench on the fromt pully bolt to get it to rotate.

Crossed our fingers and dropped it in the car. Primed the oil pump/ system and she Fired right up and held 50psi....5 years later and 10,000 miles it still holds 50 psi at high idle and have had no issues...
I hope that it is the lube I used making it "stick". Although id like to, i cant cross my fingers and hope for the best lol.
 

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Discussion Starter #19
before you tear into it remove the rear seal and try it. sounds to me like its just stiction from the rubber. thats how seals act, they grab then once in motion they slide freely.
hope that is it, ill put it on my list of things to try, it a blue fel-pro seal, feels kinda like silicon on the outside, idk though. If I take it out do i need to replace it? it has been in like 8 hours mayb lol.
 

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It doesn't have a rope seal so it should turn very easy. It shouldn't have any type of breakaway torque to get it to turn either. Anything other than this and imo there is something wrong somewhere. Loosen the rear main a little and pry the crank forward and backwards once re-torque and see if it's any better.
 
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