Repair of crankshaft

[valyidol]

Hi!
What should be the extreme size of the crankshaft repair? Rockauto.com sell bearings from 0.25 to 0.75mm. In the manual written only to 0.25mm. How long will the crankshaft after the repair to 0.5mm?

 

[bison]

Crap shoot,. it may break right of the bat or outIast a brand new crank.
I have a 6.2 with a crank ground to .0.50 ,..it's stiII running strong fourteen year Iater.

 

[valyidol]

Info from military manual:
If unable to obtain the proper crankshaft journal clearance, it is acceptable to use a standard bearing with a 0.0005 in. (0.013 mm) or 0.001 in. (0.025 mm) undersize bearing to produce clearance.
If unable to produce proper clearance, replace crankshaft.

 

[3500GMC]

I'd say if parts are hard to find (no good cranks) a re-machined crank will have to work.

No need to grind .030" off if the crank will clean up at .010". It's a good practice to pre assemble the bearings in the block and rods for measuring before the final finish grind (polish) is done to crank.

It has been said these cast iron cranks have a nitride coating from the factory. Who knows how thick this coating is, actually..

 

[Missy Good Wench]

With Scat cranks readily available cheap (And zero hours) I would not grind a 6.2/6.5 crank
I have used cranks with 200k on them that were still perfect, but even if there are no indications when they are magnafluxed, they can still break.

Sort of like bending a paperclip, how many times ?????

I opted for a new scat shaft the last time.

Crank grinding cost $$$$$ too ????

Get a new shaft

Just my 2 cents

 

[valyidol]

With Scat cranks readily available cheap (And zero hours) I would not grind a 6.2/6.5 crank
I have used cranks with 200k on them that were still perfect, but even if there are no indications when they are magnafluxed, they can still break.

Sort of like bending a paperclip, how many times ?????

I opted for a new scat shaft the last time.

Crank grinding cost $$$$$ too ????

Get a new shaft

Just my 2 cents

Thanks for your 2 cents!
But do you see were am I from? In Russia is not a new shaft. I can bay it only in US. And the cost of the shipping from US to Russia will be much more expensive the price of shaft.

 

[Missy Good Wench]

AHHHHH yes.

Gotta do what works