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Old 06-15-2008, 07:54 PM
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How difficult should it be to rotate crank?

Just got done assembling my 67 Ford 289 short block.

After installing the crank, I could rotate just by grabbing the snout with my hand. After installing pistons and rods it be came progressively more difficult (as expected). Using a 1/2 inch ratchet on the balancer bolt to rotate crank as I torqued the rod caps. By the last set of rods, I can barely get the rotating assembly to budge.

Should it be this tight?

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Old 06-15-2008, 08:26 PM
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NO! Something is wrong. You should feel just the drag from the rings. Fairly easy with a 1/2" breakover bar.
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Old 06-15-2008, 09:25 PM
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Ok, disclaimer: I don't know very much about ford engines. That being said I had a similar problem with a sbc I freshened up. (Not being able to turn the crank) Turned out some of the the rods were pressed onto the pistons backwards, and in effect the chamfered side of the rod was facing the wrong direction causing binding of the rod bearing against the crank fillet.
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Old 06-16-2008, 03:29 AM
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it should take about 20 ft lbs on a torque wrench to turn over. start disassembling in the rev order till you find what is wrong. if you get all the pistons out the crank should turn free. look at the piston rod combo for that particular cyl to determine if it is right.
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Old 06-16-2008, 05:55 AM
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How difficult should it be to rotate crank?

20 to 30 foot pounds with a torque wrench
did you oil up the rings good ?
take some light weight oil and wipe the clylinders up good .
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Old 06-16-2008, 05:28 PM
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Thanks for the replies fellas.
Yes, oiled the rings thouroughly and pins. Assembly lube on crank journals and bearings.

As I said, the crank turns nice and easy by hand without rods . And, I have new arp rod bolts which had to by torqued, loosened and retorqued three times (per their instruction). When I loosen a couple of the rod bolts, it rotates fairly freely with the bar again. Seems to get progressively tighter as I torque each rod.

All the rods are in the original location, in same orientation and pistons correctly installed with notch forward. Standard crank, I checked all the bearings were std. before installing. Machine shop checked clearances.
Any ideas what could be hanging up? Do I need to check the gap between the two rods on the same journal (seems like it shouldn't be an issue with original rods though).

I will try loosening one or two particular rods at a time to see if I can narrow down the issue.

Seems like there's always a hitch, huh?

Thanks for your input.
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Old 06-16-2008, 08:07 PM
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Well, problem solved.
I loosened and retightened a pair at a time and checked gap between each pair of rods. I was able to get a .003 feeler in all but one pair. Turns out, when I loosens that par (the 3 and 7 cylinders) the whole works freed up.

So, what was the problem....?

As usual, human error. I reversed the number 7 rod cap 180 degrees. Upon inspection I noticed the second stamping (7) was not visible from the outside. The cap and rod stampings pair up.

So, popped it off, retorqued everything, and she spins like a top....

Goes to show, you gotta check everything 3 times.

Anyone think there is anything to worry about given fact I torqued the cap backwards (I wouldnt think so)?

Thanks again for your help.
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Old 06-17-2008, 11:08 AM
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How difficult should it be to rotate crank?

i can't see how you even got the cap on if you had it 180 out because the rod cap flanges are off set .
and as far as bearings go , i've bought bearings that where wrong in the box .
man that was a hair puller , but 9000 grand found that out soon .
it was a pinto motor built to run dirt track in second gear all the time .
had to turn crank again and speed shop paid for that screw up .
seems they had mixed up the bearings some how in there boxes .
now i look at all bearings to make sure if there standard or over-sized as box reads .
hard to find good plastic gage thats not dried out from hanging on there shelves .nobody uses it as should be .
as for rods on piston right , Ive seen speed shops even screw that up when they press them on.
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