Crankshaft Welding

[Matt Wilson]

I've got a 265 crankshaft that appears to be an excellent candidate for re-conditioning, except that the thrust flange surface that contacts the thrust bearing is badly scored, and the rear seal surface has corrosion pitting.  The thrust flange looks like it has quite a bit of material missing, so I don't think just a good polishing or grinding will do the trick.  I'm pretty sure it's going to have to be welded to build it up and then ground down to size.  The rear seal surface may also need it.

My machinist said he would have to send it out to be welded, as he doesn't do that kind of work.  Can you folks tell me what questions I should ask, or what I should request they do, to help ensure I get a good weld job?  Or what pitfalls should I look for, to avoid a bad job?  Since 265 cranks are not nearly as common as others, I would like to get this one repaired, rather than try to find another one.  All the journals are standard size, never been ground down, so I think it's a keeper, but just needs a little attention in the places I mentioned.

I believe these cranks were all forged, correct?  It appears to have parting lines like a forging, rather than a casting.  Any idea what material they were made of, and heat treat they underwent?  This could influence the parameters of the weld job.

Thanks for any guidance you can provide.

Matt

[knuckleharley]

I used to work at a place called "Power Engineering" in Denver that specialized in rebuilding crankshafts,camshafts,and rods. We even rebuild the 16 foot long cranks and cams from the huge earth-moving equipment used in salt mines.

http://www.b2byellowpages.com/company-information/57500436-power-engineering-co.html

They can and did take in broken cranks,weld them back together,weld up and grind the journals grind them down,and put a layer of hard chrome on them before the final polishing. Everything done in-house. We got in cranks from all over the world. I remember some coming in from  Australia.

Now,it's been about 100 years more or less since I worked there so I can no longer personally testify as to the quality of the workers and the work done there,but I doubt it has changed much. It was a family-owned business managed and ran by two brothers who had been there for maybe 30 years at that time,but I am sure they have died by now and there is a possibility their children sold it off. Still,the basics don't change regardless of the ownership.

If Denver is too far away from you,do a web search for "crankshaft grinding" in your zip code,and then call them and ask them if they weld and grind damaged cranks.

[wayfarer]

Any competent crankshaft rebuilder should have the equipment and ability to repair the thrust. There is little difference in the process to weld up a journal or the thrust.

As to the rear seal surface, keep in mind that it has been designed and 'grooved' for a rope seal so any repair/resurfacing will have to be done in a similar fashion. The rear seal 'hatching' is not a cross-hatch, it is directional. IDK if a lip seal is available.

[knuckleharley]

36 minutes ago, wayfarer said:

 

As to the rear seal surface, keep in mind that it has been designed and 'grooved' for a rope seal so any repair/resurfacing will have to be done in a similar fashion. The rear seal 'hatching' is not a cross-hatch, it is directional. IDK if a lip seal is available.

Good to know.

[Matt Wilson]

Thanks for the replies.

Knuckleharley, I'm sure there are places in my area that will do this.  I live in the Dallas-Fort Worth area.  I will chat with my machinist about it.  Or maybe I'll call a couple of them to see if they would be willing to at least give me some guidance. 

Wayfarer, my engine does not have a rope seal.  It has a two-piece rubber seal on steel backing.  One piece is embedded in the block, and the other piece is embedded in the cap.  I imagine you are correct in saying that thrust surface weld repair is not much different from journal repair, so any competent crankshaft shop should be able to do it, but the key word there is "competent."  I had a shop do a weld repair on a seal surface on a 230 crank many years ago, and they did not pre-heat or post-heat,  and they also left the area just behind the seal surface rather rough-looking, where the weld ended.  It was not a smooth transition into the base metal.  All of that gave me concern that the crank would break, sooner or later, so I ended up not using it.  So on this upcoming one, I will definitely be relaying that experience to them.  The problem is, if they say that pre- or post-heating is not necessary, I won't know if they are correct or not, or just blowing smoke.  This could apply to any number of other aspects of the job, too,  except for the roughness, which I know is not ok.  For cast cranks, I believe pre- and post-heating are usually required, but for this crank, which I believe to be forged, I'm not sure.

[Andydodge]

Matt, I'd check out a drag racing shop or someplace that does drag racing as welding and stroking cranks is a common procedure in drag racing, maybe even have a look at a restoration shop, even places such as those that have TV shows show as F40 Motorsports(Chasing Classic Cars) and /or Fantomworks as these guys surely would have had these issues and restoring older cars with high dollar & rare engines sometimes involves complete crank rebuilds...................dunno if this helps..........andyd   

[Matt Wilson]

That's a good idea, Andydodge.  I'll see if I can find one or two of those shops to talk to, and maybe get them to do the work.

 

Thanks,

Matt

[50plymouth]

On ‎01‎/‎05‎/‎2017 at 9:57 PM, Matt Wilson said:

I've got a 265 crankshaft that appears to be an excellent candidate for re-conditioning, except that the thrust flange surface that contacts the thrust bearing is badly scored, and the rear seal surface has corrosion pitting.  The thrust flange looks like it has quite a bit of material missing, so I don't think just a good polishing or grinding will do the trick.  I'm pretty sure it's going to have to be welded to build it up and then ground down to size.  The rear seal surface may also need it.

My machinist said he would have to send it out to be welded, as he doesn't do that kind of work.  Can you folks tell me what questions I should ask, or what I should request they do, to help ensure I get a good weld job?  Or what pitfalls should I look for, to avoid a bad job?  Since 265 cranks are not nearly as common as others, I would like to get this one repaired, rather than try to find another one.  All the journals are standard size, never been ground down, so I think it's a keeper, but just needs a little attention in the places I mentioned.

I believe these cranks were all forged, correct?  It appears to have parting lines like a forging, rather than a casting.  Any idea what material they were made of, and heat treat they underwent?  This could influence the parameters of the weld job.

Thanks for any guidance you can provide.

Matt

Yes Matt - Every 265 crank is forged.  If your machinist has a recommended place he uses to spray weld and regrind the crank to standard, then I would suggest you let him do that. Nothing worse than a customer with a shopping list of questions he has gotten from an internet thread.  If the machinist doesn't have a good crank refurbish company he recommends, your are the wrong machinist.  Its pretty much that simple.  Its not a complicated process and your way over thinking this. I have literally spray welded thousands, and yes thousands of cranks and  Chrysler flathead  cranks are pretty straight forward.  Not only is your 265 crank forged, but it was also balanced to 1 gram.   When you factor in there were still major manufacturers with not only cast cranks, but Babbitt bearings when the 265 came out in 1952, you have the best of class to work with. The only tip is don't ship your crank, hand carry it and be careful as mishandling can easily  end in a bent crank!

[knuckleharley]

1 hour ago, 50plymouth said:

... The only tip is don't ship your crank, hand carry it and be careful as mishandling can easily  end in a bent crank!

AMEN! Build a wooden cradle that supports all the main journals. Cranks should be stored sitting upright,but it is impossible to ship them upright,so the cradle is necessary.