Used cam wear pattern

[1973dust]

Finally doing the timing chain and adding 4 barrel to my 74 318. Engine is currently all original with 42,000 miles. I may just be paranoid, but I think the wear pattern on the cam lobes looks funny and some of the lobes have what look like a dent or chamfer on their edges. I may just be seeing areas that didn't clean up when cam was ground. I basically have no experience with cams, so I'm hoping some of you can tell me something from these pics. Do I just need to pull the lifters one at a time and verify a rotation pattern and convex bottom?Thanks in advance for any help.

 

[Dubob]

Flat tappet cams are not ground square. The cam profile is ground with a taper across the lobe width wise. This causes the lifter to rotate along with the lifter face being convex shaped, due to this the lifter face won’t hit square all the way around the cam lobe. You could pull the lifters one at a time and make sure there are no vertical lines on the lifter body. That would indicate they’re not rotating. Me personally I wouldn’t sweat it too much. The discoloration is varnish build up where the lifter doesn’t make contact. That’s my best explanation but there are definitely others here more knowledgeable.

 

[Demonic]

Looks completely normal to me. Nothing to worry about.

 

[1973dust]

Thanks, guys. That's the answer I was hoping for. Figured I was just being paranoid.

 

[MoparMike1974]

Yep looks like typical wear pattern on a used cam. If its worn all the way flat across I would be concerned. Also look for scoring.

 

[RustyRatRod]

That actually looks quite good.

 

[nm9stheham]

Here are a couple of pix what to look for. Pix 1 is of a cam where it is just starting to show some wear. You can see a bit of a flat spot starting to develop at the higher edge of the lobe, by the arrow. The 2nd pix is of a lifter that has gone about as far as it can go. Much beyond this, and it will rapidly go downhill.

 

[Wyrmrider]

New timing chain and valve stem seals
you could check the lifters on a piece of heave glass or rock the bottom of one against the side of another just do not get them mixed up