Twisted Crank????

PJ McCoy

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So the motor I got a while back I was told the crank was warped. A friend took the same crank to his uncles shop. He said it wasn't warped to twisted. But the rust on the journals needed to be removed. Their price was very high. I think his uncle didn't want the job. Anyway. I am having a problem finding a machine shop who will check it out and give me a price. Once they here its from a 500 Cadillac they say, we can't do it. 3 shops. Do I have to find a diesel shop? It seems all the local guys want to due is chev and ford stuff. I don't get it. The cost of shipping this off would very high too.
How difficult is it to warp a caddy crank? I want to build it for turbo application. And then take my running engine and install in my truck. Out this one in my Trans Am.

Any things you older guys have heard? Younger fellows roast tires so much you warped the crank?
Is it worth fixing?
PJ
 

richie49

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Dang I would think that twisting the crank or warping it would take a lot of force! :oops: The machine shop I went to didnt say any bad when I brought my crank
and block to him .He said OK And cleaned block install cam bearings ,turned crank did a valve job And I put it together. So he knows how to do a caddy.
Richard richie49
 

5one9

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My machinist said my crank was very hard and the stone wanted to chatter. Looked and measured good in the end. I doubt yours is warped (whatever that means) or twisted. Find a new machinist.
 

Darius

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Howdy PJ,

As a confirmed Old Guy I’ve not heard of a twisted crankshaft. Over the years there have been reports of bent shafts but none of those were Cadillacs.

You are correct in that many shops only want to work on the most frequently seen engines and consider anything different a bother.

Remember not to scare a shop off by making the job sound too difficult.

d
 

MIHELA

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The crankshafts in these engines can handle 2000+ HP, possibly much more. I think the forces required to permanently deform the crank would crack the block much more easily.
 

PJ McCoy

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The crankshafts in these engines can handle 2000+ HP, possibly much more. I think the forces required to permanently deform the crank would crack the block much more easily.
That's what I was thinking. I remember Courtney saying these are as tough as any after market product.
Thank you so much.
My hopes and dreams are alive again.
PJ
 

PJ McCoy

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Bro.Darius you are correct. When I went in I started talking price due to the extremely hard material etc etc that everyone talks about. Not knowing I was just talking up more work on their part.
I've heard so many horror stories about machine shops.
 

cadillac512

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PJ-
Those cranks are not super hard or exotic. I build engines daily in a shop where we do all our own machine work and that Cad crank is no big deal to grind or polish. Not a bit different than a 460 Ford or Big Chevy.

If the rust is very deep the crank will need to be ground to the next undersize. If the rust will polish off with something like a scotch brite pad or fine sandpaper, that can be done at the shop with their polishing belt and then the crank can be measured and checked for straightness. If it looks good,polishing and measuring may be all it needs.

If a bearing has starved for oil and actually tried to seize,it will have scored the crank journal it runs on and discolored it. This can cause the crank to "bend" slightly and can be corrected in a special press and then the crank can be ground to the next undersize if not worn excessively.

I wish you were closer to KS...we could do this no sweat!

Terry
 

48Austin

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Warped Cad crank:whistle::unsure::crap:? Dun theen so Queeks Draw!!
 

PSYKO_Inc

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I concur with the others, the cranks on these engines are basic nodular iron, the thing that makes them stronger than other big blocks is the large journal diameter (2.5" rod journals, vs 2.2" BBC for example.) Cad Company advertises that they've made 2000 hp on a stock casting, so I'd imagine that a guy would have to try pretty hard to bend one.
 

Darius

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PJ-
Those cranks are not super hard or exotic. I build engines daily in a shop where we do all our own machine work and that Cad crank is no big deal to grind or polish. Not a bit different than a 460 Ford or Big Chevy.

If the rust is very deep the crank will need to be ground to the next undersize. If the rust will polish off with something like a scotch brite pad or fine sandpaper, that can be done at the shop with their polishing belt and then the crank can be measured and checked for straightness. If it looks good,polishing and measuring may be all it needs.

If a bearing has starved for oil and actually tried to seize,it will have scored the crank journal it runs on and discolored it. This can cause the crank to "bend" slightly and can be corrected in a special press and then the crank can be ground to the next undersize if not worn excessively.

I wish you were closer to KS...we could do this no sweat!

Terry

Professor,

Dang, but I’ve missed you!

Take care of yourself there in South central/eastern Kansas. Expect a visitor passing through once this plague is gone. (This constitutes your only warning)

BE Blessed,

bro. d
 

PJ McCoy

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PJ-
Those cranks are not super hard or exotic. I build engines daily in a shop where we do all our own machine work and that Cad crank is no big deal to grind or polish. Not a bit different than a 460 Ford or Big Chevy.

If the rust is very deep the crank will need to be ground to the next undersize. If the rust will polish off with something like a scotch brite pad or fine sandpaper, that can be done at the shop with their polishing belt and then the crank can be measured and checked for straightness. If it looks good,polishing and measuring may be all it needs.

If a bearing has starved for oil and actually tried to seize,it will have scored the crank journal it runs on and discolored it. This can cause the crank to "bend" slightly and can be corrected in a special press and then the crank can be ground to the next undersize if not worn excessively.

I wish you were closer to KS...we could do this no sweat!

Terry
Terry, its nice to hear from you. I too with I was closer to your shop. I've been saving some cash and now looking to build a little better Block than what I have.
Thanks for the help Terry.
PJ
 
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