Thread: Bad Comp cams lifters?

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I was talking to a engine builder about some valve train nose in a rebuilt 351-W I have,he was telling me they had problems with lifters from Comp cams. I never got a cam card with the motor so I dont know the manufacture but he told me most use Comp cams and if it is from them that is most likely the problem. Anybody have problem with lifters from them.

Not a lot to go on here Jeff, but here's a possible explanation (assuming it's a flat tappet cam we're talking about).

Your builder is correct in that there are, "... a lot of problems..." however, it's not the lifters as much as lack of proper break-in.

Nearly every late-model production engine now uses roller lifters and as such, the nice folks at American Petroleum Institute (API) have lowered the ZDDP (zinc dialkyl dithiophosphate, or more commonly referred to as just "zinc") levels in motor oils listed as meeting the current SM oil rating. Simply stated - modern oils are sans the zinc we used to have and they do not protect against the extreme friction at initial start up.

Many people will install a replacement flat tapped cam and fail to read the instructions and just fire up and go... Sad story there. If break in instructions are not adhered to, things will go bad - usually cam lobes - but lifter faces are subject to tremendous stress on start up as well.

So probably the situation is traceable to initial fire up and lack of zinc additive. It's critical for the first 20 minutes as the wear pattern is irreversibly established at that time.

My two cents,
Glenn

When I broke in the motor the zinc was being reduced and knew nothing about it,if its a bad lobe I would think it would have shown up sooner as the motor has made 3 trips to Florida and runs great except for what sounds like one lifter making noise which is getting slightly worse. The builder of the motor installed the wrong cam and would like to replace it but since he had a questionable reputation I am afraid I am going to open a can of worms since it does blow some oil out the breather.

there is some lifter issue s and i know abit about whats going on . i am not going to post up on a open form as to whats going on with there lifters in the past or till now .oil has had a lack... of zinc.. that is true.. but the increase of detergent is the real deal with any goodwill any small bottle of zinc can combat would be offset by oil that is hi in detergent.added zinc may set in the oilpan .that why i buy made break in oil .from joe gib or brad pen

I hope its just a bad lifter or a rocker arm and nothing serious,I plan on tearing into it this winter to see if its something simple. I am going to pull the valve covers off and bump the motor over and see if all the valves are opening and if they are I might change the cam to the one I wanted and check all the rocker arms and push rods for wear,if its a bad cam I will look for another motor to get me by until I can build the motor I really want.

a bad lifter/cam is a serious deal. wiping a lifter puts alot of hard iron particles up on the cylinder walls cutting up bores and imbeding iron in pistons skirts

I have not noticed any metal particles in the oil when it was changed and if its a lifter I hope its a internal part,I cant get the lifter to make any noise when driving around here and can go a couple hours without any noise but when I got to Florida its noisy by the time I get there.

open up the oil filter

could be more then a cam or lifter . what rocker arms do you have stud or pedastal mounted ? if stud rocker ball or nut backed off. pedastal could be wearing away or preload was never right

I will cut the filter open when I tear into the motor and it has the newer pedestal style rocker arms,it was supposed to have new rocker arms but the builder could have cleaned up used ones.