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TR4/4A Tappet wear pattern inspection - normal or not ?

blhazzard

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I have a 67 TR4A with 144k total miles and 50k miles since cam R&R and bottom rebuild.
Took the head off to repair a broken manifold stud (manifold side ports were out (-6 and -23 mil with respect to center port) ... the -23 side is where the manifold bolt broke...

Anyway...
I pulled the tappets out to clean and inspect and have attached pics of the wear pattern.
#1 is forward most tappet and #8 is rear most tappet.

Can anyone comment on the wear pattern ?
Normal ?, Expected ?...
 

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It doesn't look like they rotated at all in the bores. Either the tapped should be slightly crowned, or the cam slightly angled such that the tappets rotate a bit each time. At least as I under stand it all.
 
It looked like #2 and #8 rotated for a while ... but stopped.
Most of wear pattern look like a mono/bi quasi-stable position...
Looking at how the things is supposed to work I would have expected a round pattern... not this...

These are probably OEM (1967) tappets... Replace them ?

Anyone have any experience with the Moss "lightened tappets" ?
https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=66138
 
I always thought the originals were the best tappets and there have been lots of problems with soft reproductions. These definitely are turning. Ether too tight in the bore or wrong profile to the cam lobe. Anyway I'd check your cam too and may be some problems there also. You can have the cam and the tappets reground and hardened. I sent mine to Delta Cam Shaft in Tacoma Washington and had repairs to the cam and a new profile ground and close to 15k miles now and no problems. I even auto crossed several times.
 
Got_All_4,
Thanks for the advice.
I have not done a hard look at the cam yet since it and the engine are in the car with just the head off.
Will do...

The engine was pulled and cam was r&r about 45kmi ago due to some odd cam issues.
Need to talk to the PO and review maintenance records.
The bottom was done at that time also..

Thanks again!
 
I live in Tacoma and delta does a lot of cams. I wonder last time I was in there where did all these cams come from. It never dawned on me that people would send stuff to them. I am no expert on cams or lifters, but the lifters I have seen all had an even dished pattern that just had to be flattened out with a resurfacing. In today’s world you could probably seed Delta those pictures and ask them what they think. My take is that the adjustment was too tight or like suggested for some other reason they did not turn and wear evenly.
 
Wow, those are some soft lifters! They are beyond repair and I would do 2 things, replace the lifters with some from APT and take a good look at your cam. If the lifters are that worn the cam had to suffer, but to what degree? Delta, like most machine shops can re-profile lifters for pretty cheap, but those are long gone.
Rut
 
I would not be too concerned about the lifters spinning, once they wear a pattern in the surface they won't tend to spin. My original lifters have little wear but a definite stationary pattern. However, in my experience, yours have way too much wear. I don't think some of the aftermarket lifters and cams are very good. No telling what the metallurgy is like with those lifters so I don't think I'd have them ground and hardened. I would not hesitate to have original lifters done however. I would also buy replacement lifters from one of the cam specialists rather than the "big 3" and the like. Also try some ZDDP oil and 2000 rpm break-in.
Tom
Edit: Here's an original lifter with about the same mileage.lifter.jpg
 
Note the pics may be somewhat deceiving.
While the wear looks bad the wear is barely perceptible to the touch.
The "black" areas are the reflection from the camera.
I was mainly worried about the "shape" of the wear pattern and it implication to cam health.
I am doing a close cam inspection today... well as close as I can without pulling it out.

Everyone ... thanks for the comments.
 
Cam lobe pics..
Pic 1 are bobes for Cyl 1
...
Pic 4 are lobes for Cyl 4

Any comments...I have yet to measure dims of lobes..
 

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Cam lobe pics..
Pic 1 are bobes for Cyl 1
...
Pic 4 are lobes for Cyl 4

Any comments...I have yet to measure dims of lobes..

I wonder about the uneven pattern. Was the cam new or reground at the previous teardown? Can you feel the areas that seem discolored? The mic readings should tell the story.
Again here is a spare cam with about the same mileage.
Second comment: you are a much better photographer than I.
P1010047.jpg
 
I put Moss lightened lifters in my car 8 years ago. I've had no problems that I know of--but I sometimes wonder why I'm so easily swayed by catalogue language like"new and improved" or "high performance" or "uprated."

My guess is that a good cam shop would have directed me elsewhere.

At eight years out I do hear a "tapping" sound at idle, and after three tappet adjustments I've failed to eliminate it. I've wondered if it could be a bad lifter. Anyway, brighter folks than me can comment on lightened, new and improved and uprated lifters.
 
As it's been said before, does it sound like a typewriter? If so, everything is working like its susposed to...if you have to chase the adjustment you may have cam or tappet wear.
Rut
 
I am wondering if proper break in procedure was followed with a good cam lube in place. It looks to me like the grind finish on the cam lobes and journals was not very fine. It appears the burnished the lifters leaving the imprint of the lobe surface on the lifter. The cam looks to be harder than the lifter. By the time I tear one down the lifters usually are pitted, so I have not seen this pattern before.
 
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