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TR2/3/3A TR3 Camshaft Needed for Regrind

Tinkerman

Darth Vader
Offline
Evening All:

Really need some help!

Found out today that my tappets are trash and because of that the camshaft needs to go. Talked to Ken Galander and he can get a camshaft reground for me but I do need a regrindable core to start with. Due to the way the tappets looked I suspect that my camshaft is wuthless. If anyone has a regrindable TR3 camshaft I would be happy to buy it from you to solve my problem.
If you have one or know someone that does please let me know. My eMail address is in my profile so just post me or PM me.
Thanks for your help, really would like to get the engine done, sigh.
Thanks, Tinkerman
 
don't be too hasty there.
cams can be repaired easier than you think. I had a cam repaired and reground by my local cam grinder for my truck once. it had a chunk out of a couple of lobes. it was out of my diesel landcruiser so replacement costs BOTH arms and legs. they spray weld with some exotic metals and is still in use today. they beveled the edges of the lobes so that it would not do the same thing again (factory did not bevel the lobes in 1981). it cost $135 canadian.Best money ever spent. The company is Shadbolt cams in vancouver b.c. They used to do all the catterpillar cams for Finning tractor (2nd largest cat dealer in the world at that time)for all their remanufactured engines as well as anything else.
Rob
 
Tinkerman - How did your tappets look when you took them out. At 80,250 miles from new 3 of mine had grooves in the flat bottom. The other five had finely polished circular marks on them as they are supposed to have. This is because the center of the tappet is not centered on the cam and this causes the tappets to rotate. All I did was lap them with 300 grit sandpaper supported on a piece of 1/2" thick glass that I know is flat. After I got the bottoms all flat again, I put them back in the engine. That was in 1990. I just took them out last week and one has a flat wear line on it indicating it had not been rotating and seven looked perfect. I smoothed the "bad" one by lapping it as above and I also did the others a bit while they were out. During that interval, I drove 94,000 miles and I plan to put them back into the engine. There was a rash of tappets a few years back that were sold as replacements and these had not been hardened. They would only last a few 1000 miles. I also heard about camshafts not lasting after a re-grind. Maybe the re-grind went through the case hardening or maybe the engine should have been broken-in using an oil with Zinc in it.
 
all cams that have been ground MUST be re-hardened. nitriding is best. if the cam grinder does not do this then don't use them, find someone else. This is not an option. flat facing the lifters as you say may have worked for you but i wouldn't suggest it. if you can do this then the lifters are obviously too soft, they will ruin the cam. it may look ok but if you mike the cam the profile will be ruined. it's not just about the total lift at the peak, it's about the shape to get there and back.
Rob
 
it has been proven that ceramic lifters SAVE camshafts from wear. we are talking about rockwell C-scale of over 90 (if i recall). reduced friction and almost no wear on the cam because of it. many of the lifters supplie for our cars aren't even Rc-50. you may not have a significant problem but chances are that the hot cam you put in is no longer a hot cam. Just worn out.
Rob
 
The guy I worked for circa 1970, during the day was a tool and die maker, and consequently knew pretty much what he could do back then from a resurfacing standpoint. I remember that if after measuring the lifter length if one pass on the surface grinder(about .0015)did not cleanup the face it usually was a throwaway. The average lifter probably didn't have more than about .005 of hard surface to begin with so if you removed more than half it becomes mechanically weak and will start flaking off in large pieces. I did have one fail on me but it had been in the car for 20+ yrs. Folks are right to be worried about the declining zinc content of oils. It is a cause for concern down the road so to speak.
Tom Lains
TS8651 & 58107
 
My cam has never been out of the block and I still plan to use these original tappets when I put the engine back together again. I'm sure I haven't removed more than half a thou from the lapping I did and who knows if the new ones would be from the batch of soft ones or not. In the past 5 years (over 50,000 miles) since I had the inserts done for the exhaust valves because of lead free petrol, I have never had to re-set the valve clearances. This tells me that my tappets and push rods are working just fine.

As for braeking in new flat tappets and a cam, read what Crane Cams has to say about this and oil with Zinc and how to do it.

https://www.cranecams.com/pdf/548e.pdf

Don Elliott, Original Owner

https://mysite.wanadoo-members.co.uk/trebor/don3a_big.JPG
 
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