383 Crankshaft Removal

[ktneifert09]

Took my 383 apart and scratched the crank.     Now we'll have to take that apart too.  Any tips on what to do at this point?  Getting the front damper off appears to be a big challenge because the engine just turns and the fastener is huge.  Is there a standard amount I need to have ground off so I can buy new rod bearings to match it?  Any help that folks can provide would be appreciated.  Desperately in need of tips, tricks and sources of information.
Thanks all!

[lisiecki1]

generally you'll grind in increments of .010..... for instance a typical cleanup would be called a ten-ten (ten thousandths off the mains, ten thousandths off the rods)

as far as the damper bolt, you can wedge a screwdriver handle between the crank and block somewhere to lock it up so you can break the bolt loose...

how bad is the scratch?  is it too deep to polish it out yourself?

[ktneifert09]

The scratch has both a raised section of maybe a .002-3 and some indents that are the same depth.  I didn't know how sensitive the whole systems is to this sort of stuff so I didn't want to try and file it and polish it.  If I wanted to try this, what approach would I use?
BTW - Thanks for the reply.
Oh - and if I do pull the crank - the bolt is not LH or some goofy thing like that, right?

[ktneifert09]

Oh - and one more thing.  While we were fiddling with it, we ran the bearings over it to see if they would snag and that created some very light scratches in the bearings (<0.001).  My thinking was to ignore these since they aren't raised and they aren't deep.  Or I could buy new bearings.

[lisiecki1]

I've always treated the bearing surfaces as one of the most important parts of the build, so you may want to go ahead and have it turned being that you're dealing with high and low spots, they may just be able to polish what you have and get away without removing much material at all.  I wouldn't be overly concerned with less than a thousandth of a scratch on the bearing, typically i drag a finger nail over the surface and if it noticeably grabs the nail then I replace it or have it fixed.  You can attempt to polish your journals yourself....it takes a long time, but some light emery cloth and wd-40 can get you there.  The damper bolt should be standard right hand thread, but i'll double check the 383 when I get home just to be positive.....odds are you won't be breaking it even if you turn it the wrong way to a point because I believe the factory torque spec is around 130 ft.-lb. or so and that bolt is huge, I can also check that torque spec. for you if you don't have it.

[ktneifert09]

Thanks very much.  I have the torque value - I have a reproduction manual that says it's 135 ft-lbs.  I went and broke out the calipers and the high point of the mark looks more like .001 than 2-3.  The low spots seem really minor.  I think I'm going to try polishing it and see how it comes out.  I've got nothing to lose except time and effort.  I can always get it turned.  Thanks for the tips - they have been great. 

[John_Kunkel]

Get a flat smooth file and use it to back up the emery cloth, keep it moving and keep it wet. I've dressed out lots of crank blemishes that way.

[69DodgeCharger]

Get a flat smooth file and use it to back up the emery cloth, keep it moving and keep it wet. I've dressed out lots of crank blemishes that way.

How big of a scratch? What grit? Would one have to worry about a "flat spot" on the bearing surface in the scratch area? what if it involves the radius at the edge of the bearing surface?

[green69rt]

Thanks very much.  I have the torque value - I have a reproduction manual that says it's 135 ft-lbs.  I went and broke out the calipers and the high point of the mark looks more like .001 than 2-3.  The low spots seem really minor.  I think I'm going to try polishing it and see how it comes out.  I've got nothing to lose except time and effort.  I can always get it turned.  Thanks for the tips - they have been great. 

I'm sure you know to hot tank or clean the crank when done.  The grit's going to get inside the oil hole and other places, also since you have the crank out why not camfer out the oil hole a little?  Makes for better oiling of the mains. Just a thought.