Tappet noise with new cam

Right. The question is how much damage and if it's toast now. Got a few hundred miles on it. I'll know hopefully this weekend.
 
Right. The question is how much damage and if the cam is now toast. Hopefully I'll know this weekend.
 
Pulled out the cam today; wear rate is visually very high considering there is less than 1000 miles on this engine, and is concentrated in one spot on the lobe. I can't measure a height difference with a micrometer, but the lobe is certainly rounded where it has been scraping the edge of the lifter. Maybe the larger diameter single lock lifter will bridge over this worn area and get enough support from the unworn edges to be okay. Would sure beat buying a new $400 cam. Wish I had known about the necessity of using a specific lifter before installing the cam.

I removed this with the engine in the car but I'll take Purdy's sage advice next time and pull the motor out.
 

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gilitos said:
Pulled out the cam today; wear rate is visually very high considering there is less than 1000 miles on this engine, and is concentrated in one spot on the lobe. I can't measure a height difference with a micrometer, but the lobe is certainly rounded where it has been scraping the edge of the lifter. Maybe the larger diameter single lock lifter will bridge over this worn area and get enough support from the unworn edges to be okay. Would sure beat buying a new $400 cam. Wish I had known about the necessity of using a specific lifter before installing the cam.

I removed this with the engine in the car but I'll take Purdy's sage advice next time and pull the motor out.
Click to expand...


You should call Bill and ask him. If it is to bad he can regrind it for you. Bill is a good guy he will tell you what to do.
 
Yep, those are exactly the same marks I had on my cam using the small lifters. The center gouge may well have worn through the outer hardening, or certainly reduced its depth, so it would not last long even with correct lifters. It should be re-hardened if it is reground. The instructions should have told you the size lifters to use. Be sure the lifters rotate when you reinstall them.
 
The hardening is usually about .080 to .090 deep. No problem regrinding it a couple of times.
Aside from that, the finish on the unworn part of the lobe looks like it was done on a bench grinder. I'm surprised Bill would let something like that out.
 
I've always used the single lock lifters . Bill Told me to use the large base single lock lifters when I ordered my cam. Mine is a 3/4 race regrind but the large base lifters are really better for any cam if you expect to get full specs on duration.
 
"but the large base lifters are really better for any cam if you expect to get full specs on duration."

Wrong! If the cam is designed for a 1 inch lifter, increasing the face diameter will only add weight to the valve train.
 
Send it back to Bill as to be checked
Ask him to supply correct lifters and valve springs to suit the cam
Remember different cams need different valve springs
 
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"Aside from that, the finish on the unworn part of the lobe looks like it was done on a bench grinder. I'm surprised Bill would let something like that out."

Hmmm.
Look closely. The copper plating is nearly gone. Wonder if the cam also overheated....that would throw off the appearance of any of the rest of the surfaces.
 
tbirdtbird said:
"Aside from that, the finish on the unworn part of the lobe looks like it was done on a bench grinder. I'm surprised Bill would let something like that out."

Hmmm.
Look closely. The copper plating is nearly gone. Wonder if the cam also overheated....that would throw off the appearance of any of the rest of the surfaces.
Click to expand...

Look closer. It was glass beaded after heat treating to take the scale off.
It has not been overheated.
 
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