I had the block prepped for a refurbish. no boring. Just cylinder prep, cam bearings..... I've had the block bolted to a stand, oiled and bagged. Callies forged Crank polished and sitting in box standing up in the corner from the previously running motor. everything was fine when I took it apart. really just needed new racing rings. blowby and the end gaps had opened up. putting out blue smoke at WOT.

Well I let it sit for three years.

When i put the crank in it spins Okay. Even a little stiff. As soon as I put on the main caps with 5 foot pounds you couldn't rotate it. I was thinking my new clevite H bearings. So I measured the crank to bearing surface and it was all good. I then put the old bearings in and the same thing. new bearings were right at the .0025 clearance

I'm thinking that the block warped somehow on the stand and needs an align bore or the crank is now out from standing in the corner.

any opinions?

 

I think you're right, and it could be either the block or the crank or both. You'll probably have to take it to a good machine shop to have it checked out and corrected.

 

best to hang/suspend cranks

 

gkull, when you say you can't rotate it, do you mean by hand or not at all?

Is it possible to isolate it to any specific journal or combination of journals? Perhaps by loosening all of the caps and then tightening them one at a time. I guess what I'm implying is if you loosen all the main caps and can turn the crank as you could earlier, then for instance tighten the center main cap. If the crank now won't turn, or tightens or loosens as you do rotate it, that might imply the crank is the issue vs the block.

You mentioned that the crank was "sitting in box standing up in the corner". Is it possible someone knocked it over at some point without your knowledge and then stood it back up? Also you mentioned it was polished, was that before it had been in the previously running motor, or after it was removed and placed standing in the corner?

I must say I've never heard of something like this happening.

Good luck and do keep us informed on what you discover.

GUSTO

 

got any V blocks and a mag base indicator?

 

No "V" blocks. I'm hauling it down to the race engine shop to check for align hone or boring and crank being straight

 

If not, just set it in the block without caps and indicate all the mains to look for runout.

 

I don't think standing a crank would collapse it on some way. I think the only way it would be damaged is by knocking it over.
I'm thinks we're the main caps seated and tourqued when stored? This is interesting I'm sure a trip to the machine shop will show the problem.

 

No main caps or anything. That is a 44 pound Callies pendulum cut 4 inch stroker crank that used to do 7500 rpm lap after lap. I'm dropping the compression down to about 11 and running 1.6 intake and 1.5 exhaust to get .685 I and .660 E I'm trying gapless total seal rings. 4.155 bore

I'll still try and keep up with the 650 HP vettes

 

Reminds me of a 2 bolt main 396 i bought the main caps had been mis numbered. i put the crank in put the balancer on the snout it would not even turn over by hand. Changing around the caps It turned over easy like it should have by hand. Ya you probably will end up honing the mains.

 

A crank will not bend by sitting around, regardless of the orientation and a block will not bend by hanging on an engine stand. This is somehow user error.

 

Buy a good machinist straight edge and lay it in the main saddles then try slip a 0.001" feeler gauge under it.

If you use enough plastigauge you should be able to locate the tight area.

 

The V-block, the indicate the mains with a dial with no caps and the straight edge along the journals are all excellent advice......use the three to come to a deduced conclusion.
Do you want to save time? Remove each cap starting at the front or back and spin the crank.......if it still spins hard after doing one cap at a time......remove two at a time.
Never seen a crank or block "move" due to storage......**** is just too stout.
Let us know what the machinist says about the line hone.....

Jebby

 

It spins free with # 1 (front) and #5 Rear main caps installed. Add # 2 it gets rotating resistance. Add # 3 or 4 and you can't rotate it by hand even with the old used main bearings. It's going to the shop today. This Motown block has had a tough life. It was originally a Bill Mitchel Hard core racing 625 hp crate motor. It was a H-roller. It suffered valve train failure snapping off and pounding two intake through the valve seats sideways. AFR did a beautiful job of welding the heads back to what appeared to be brand new. It got a couple of pistons, balanced and I went to a solid roller 252/256 .685/.714 Then back to Road racing and driving at the max.

Within a year I was running it through the gears and actually had let off when I heard/felt something. It was the crankshaft breaking in the #4 rear main. I just stabbed in the clutch and put it in "N" and coasted off a return exit road because I was going about 120 mph. So much for a scat 4340 forged crank.

It was a 350 mains lighter crank. It damaged the block in the #4 main. So they bored the mains to 400 crank diameter and I bought this super Callies crank. The 1.5 mm racing rings only seem to last about 5000 miles. Every year or two I was reringing it. This was just another time,

http://www.superchevy.com/how-to/010...block-solution

 

Always enjoyed a good mystery. T

 

Correct. Old wives tale BS. If a hefty crank does not bend with tons of forces on it while spinning, it certainly is not going to warp standing upright.
Wood warps, iron doesn't. Plastic warps, iron doesn't. Aluminum warps, iron doesn't. Vinyl warps . . . . . . .

 

Perhaps a crank will not bend just sitting around but that does not mean that its not bent. Fortunately, a crank can be straightened quite easily if the shop knows what its doing. I have had this done.

 

I put my eyes and hands on a severely bent / bowed / warped stone gravemarker.

At historic early nineteenth century church-churchyard cemetery. Was either granite or marble; don't recall which. About 2 1/2" thick. Was outdoors & propped up against rear of sanctuary at about 70* angle with engravure facing up. Because of lichen, time & weather toll, could not resolve engravure. I cannot explain physics of stone bowing / warping; but I don't doubt there are technical answers.

WTF's a stone got to do w/ cranks ? Don't always trust your intuition to predict the wonders of our physical world.

FWIW, all shops I've used have racks where cranks hang vertically from flywheel or flywheel flange. And the comment above about brake rotors being stored flat is correct as well.

 

Another HAPPY ending! posters were right that I was partially to blame!

I hauled it down to the race shop who had done the align honing and install cam bearings and we lifted the crank out. the machinist straight edge fit perfectly. He started looking at the caps that had been restamped and a direction arrow engraved. Then he looked at the installed bearings in #2 and #3 had been engraved with a wrong direction arrow. So the bearing key tabs ended up on opposite sides instead of lining up.

I didn't think that they would mark a wrong direction and I didn't even think about the bearings orientation. I just cleaned everything with brake clean and snapped the new bearings in place. My bad! So it is back onto assembling!

 

I had a feeling...but wasn't going to say anything because I don't question other builders........but this has got me once before too.....sometimes the "arrow" is cast on the cap so poorly, it can look like it is pointing the opposite way.....
But good it was nothing major! Chalk it up as a win......

Jebby