repair cam journal

Here is another suggestion.
 

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cmbrucew said:
Here is another suggestion.
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I'm not trying to be smart here, but would this really work? I'm a great fan of JB Weld; I used it to repair stripped out threads in a Corvette vent window regulator and it is still holding after 5 years, but to repair a camshaft journal? Have you done this? It sure would be nice if it worked. I'm just having trouble getting my head around repairing a bearing journal with what is essentially, high grade Bondo.
 
tubman said:
I'm not trying to be smart here, but would this really work? I'm a great fan of JB Weld; I used it to repair stripped out threads in a Corvette vent window regulator and it is still holding after 5 years, but to repair a camshaft journal? Have you done this? It sure would be nice if it worked. I'm just having trouble getting my head around repairing a bearing journal with what is essentially, high grade Bondo.
Click to expand...
No Denny I have not tried this. First case like this I have heard about, so if I understood the problem correctly, it is like a small piece missing from the outside tread of a tire. Still plenty of bearing surface. Say a .625" wide journal with .125" missing, still have .500". I would think JB Weld would
be suitable repair with no serious failure hazards. JMHO.
Bruce
 
>>>This was not a cheap exercise>>>

Repeat the exercise anyway. Send the bill to your machinist.

Jack E/NJ
 
OK, am I the only one that missed the picture? That is the only way to get a good idea of the needed repair.�� Gary
 
send it to a machine shop that welds up throws on crank shafts ive had a 4 throws welded on my merc cranks and ground back to standard with no warping, if where the gouge is welded it should not cause any warpage on the cam shaft, the whole journal does not need to be welded just a little way past the damage, and that cuts down on the heat applied to shaft and less chance of any warpage
 
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WestCoast said:
send it to a machine shop that welds up throws on crank shafts ive had a 4 throws welded on my merc cranks and ground back to standard with no warping, if where the gouge is welded it should not cause any warpage on the cam shaft, the whole journal does not need to be welded just a little way past the damage, and that cuts down on the heat applied to shaft and less chance of any warpage
Click to expand...

This makes a lot of sense.
 
I just can't get passed the fact that you put an L-100 grind on a steel shaft. I really don't think the profile and lift rate weren't this. Been running these cams for over 20 years and have never heard od anyone having any ware problems, In a race engine we only run 60/65 lbs spring pressure nad #50 on a street engine and can turn over 5K with no trouble. Had the Hydro up to 6K
 
Hey boys, thanks for the suggestions- wow! there has been a lot of responses. I am a machinist myself, but do not have access to a cylindrical grinder, hence had to farm the job out. We, the machinist that had the woops moment, and myself have had a good old discussion re. repair of this. He didn't even know it was steel; thinking he'd have to metal spray it. Sleeving is out- no way you could pass a sleeve over the end journal, let alone the lobes.We sort of agreed that slowly building up the damage with mig, allowing time to cool between passes, would give least amount of deformation. [as JWL suggests] As he said, he has the undamaged half of the journal to set up off, all good in theory, but I'm still concerned about maintaining perfect concentricity of each lobe. Then I, like Bruce, thought of JB weld, or some sorta epoxy. We used to use an epoxy at work called Devcon? I think, which was supposed to exhibit exceptional wear properties, so thought I'd throw this out to all you learned fellows on the 'barn to see if anyone had a 'magic' solution.
As Kurt says it is his problem- well, I'm afraid old boy it is also my problem. **** happens, I just want to fix it, move on, and assemble this engine.
Jack E sure thing, you are so correct, however, first thing is to find another steel camshaft in good enuf nick to regrind, then ship it to the States, wait an eternity for Tony to work his magic, and get it shipped back. I'd prefer to have a go at fixing this one first before I follow your suggestion. But you are right....
Thank you boys...
 
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Old Ron, Steel cams are just one of my things; all my engines run them- why not? The engine this camshaft is destined for also has a steel crankshaft. Before you tell me Fords never had steel crankshafts, I didn't say it was a Ford crank did I?
It will also be running Ross pistons, NOS conrods, nos big block Lincoln oil pump, new everything,down to 16 hardened valve seat inserts, spent a fortune on the damn thing!
I agree, Ford cast iron camshafts give no problems, but I prefer to use steel exclusively. I do tend to 'overdo' things, but as I said, just one of my things.
 
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I hesitated proposing this. What about welding a piece of steel over the damaged area? Less welding. I also thought of brazing a piece on. I have used JB Weld for a lot of things. Repairing hydraulic cylinder rams for one. I would always wonder if it was ready to let go.
 
Yes, I've used Devcon reparing alum heads and it worked very well. unfortunately I don't think their in business any more.
 
I would advise against a plastic repair, what ever you repair it with ( silver solder has low melting temp and the hardness of brass) make sure it can take saturation in hot oil very hot at the point of friction, and survive many heat cycles, if it fails you may plug up a journal and ruin a motor for a cheaper fix. If it's steel clean it, silver solder, and grind. if it's not too bad of a scar leave it for an oil pocket, the rest of the width of the jounal can carry the load.
 
Brian, you've gotten a lot of suggestions on how to repair, but I don't see a lot of first hand experience-real life examples of what has been tried, what has worked and what has not worked. I suggest to keep searching until you find someone who has actually done such a repair himself. No second or third hand opinions allowed!
Try antique engine rebuilders, heavy truck engine rebuilders (which engines use steel cams and rebuilders try to reuse everything possible), or specialty machine shops. A friend's dad ran a shop that specialized in building up and regrinding printing press rollers and such. These places likely have experience with how much distortion takes place when building up with weld.
 
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