new comp hyd. lifters keep bleeding down

[3rdelke]

not sure what the problem is. different ones seem to leak down. motor still has break-in oil in it, after I installed roller rockers the upper valve train seemed noisy, pulled the valve cover, lifter not pumped up, ran it a while, pulled the valve cover, the aforementioned lifter was good, but another one was soft... I cant remember what lifters they were as they came with the car. the tech at comp said there are two different preloads, the press fit lifters are to have .002 to .004 preload, the spring clip type .030 to .060 respectively, not sure the preload would account for them leaking off and you can run the engine for a while and they don't pump up. thanks, bob

 

[benno440]

gone through 4 sets of comp lifters and all did the same thing, switched to lunati and never had a problem for 2 years now

 

[3rdelke]

benno, was afraid I had heard that, guy at comp did say "they may have failed" I may try to give them a full turn of preload...Oh well...thx...Bob

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wonder if I will need to have another set of push rods cut if I change lifters

 

[lewtot184]

i'll step out on a limb here. a couple years back, and i can't remember if it was a magazine article, comp cams admitted their hydraulic roller tappets were failure prone. something to keep in mind is that comp cams or any other cam grinder does not make their components and i don't know who makes comp cams rollers. i'm not sure anyone makes a good hydraulic roller tappet, but Morel seems to have a good rep. what one needs to do is find out who's making tappets and which ones hold up the best. i think the aggressive nature of these aftermarket roller cams kill hydraulic tappets. i also believe that there isn't any "motor messiah" on these mopar websites who knows good from bad on these hydraulic roller tappets. i recommended on another website to get on speedtalk.com or yellowbullet.com and find some real cam people with experience in this area. what brand are the chevy guys running that holds up? they make big power and the internal workings of the tappets are probably the same from one engine to another. i'd also think about calling Isky and see what they're doing.

 

[3rdelke]

lew we have flat tappet hyd, not a roller cam, we did just put on roller rockers, and just had smith bros. make our push rods. I just found the box the lifters came in...comp pro mag 867-16. thanks on hold with them now, may just order the lunatis

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comp said they may just be noisy, said same lifter as lunati.

 

[lewtot184]

sorry for the misread on my part. you engine probably has the Stanadynes tappets in it. comp, and everybody else, sold a bunch of them and they're crap; went thru a couple sets. make sure your getting Johnson tappets. this is a problem with cam grinders who really don't make much but outsource a lot. it's a pain in the butt to have to chase who manufactures the parts you trust to be good.

 

[3rdelke]

lew, thanks again. think there is any danger in running these for a while?

 

[Cranky]

You say you still have break in oil in it? How much run time is on it? Once I break in the cam, I change the oil to whatever the customer wants. Moly rings break in pretty fast and well, the bearings really don't need a break in oil. Why not go ahead and get the break in oil out of it and see how it acts before making other changes?

 

[747mopar]

I sent a couple sets of lifters back to Comp because they weren't pumping up, the second time I asked them to replace the cam and lifters for a solid lift........ 6,500 miles later and still no problems. Both times I sent them back they confirmed they were bad, I hope they got it figured out because I like Comp Cam.

 

[3rdelke]

cranky, its only got about 100 miles on it but that's probably good advice. 747 mopar, we would like to do the same thing, would upgrading to solids require another set of pushrods?

 

[lewtot184]

as long as they're rotating they won't break anything. another point here; these newer aggressive hydraulic cams will have some clatter due to the fast closing ramps; but not a constant tick like one or two tappets aren't pumping up.

 

[hunt2elk]

On Friday we dyno'd my new 451 build. This is the one where the #4 cam bearing spun and the top end ran without oil. I replaced the solid lift for a custom hydraulic grind from Racer Brown. He said that there are only a couple of manufacturers making lifters and in his opinion, Johnsons were the best and is what he recommends. So I bought a set from him. We broke in the motor for 20 minutes and made 10 pulls with no issues. After that, we started to hear some noise from the top end. It was progressively getting worse. I had to leave, but the builder said they were going to remove the valve covers to investigate. He called back later and said that 5 of the new lifters weren't pumping up and that you could compress them with you fingers. He had a set of Comp racing lifters in the shop and installed them. Made a few more pulls, and all the noises were gone. He said they have 4 sets of new lifters sitting on the bench right now that did the same thing. These were the first Johnsons that they had go bad though. Apparently lifter quality control is not the greatest right now.

 

[Yatzee]

I have used only Lunati products in the past 20 years and have never experienced such an issue as this. I think it's an absolute shame that you should have to disassemble your motor for such a trivial thing. How hard can it be to produce and test their products before marketing? I agree that some of the "wilder" cams cause havoc with lesser quality lifters but the manufacturers should take this into consideration as they make both cams and lifters so I suppose we should deal with companies that have only track proven records. I will pass on to all posters that the best pushrods I have ever purchased came from Trend Technologies in Michigan and can assure you that these people know their stuff. I also advocate the use of a rod length checker for all new cam/lifter installations before giving them a call - it'll be the first question they ask you. Pricey? A bit, but then you only get what you pay for and removing an intake due to a faulty valve train has got to be worth the extra $50 you pay over other manufacturers products. Hope everything works out for you, you've been seriously inconvenienced.

 

[lewtot184]

all this is a perfect excuse to go to solid lifters. the solids will idle better and make more power thru the whole power band.

 

[65 Coronet]

I'm on my 2nd set of comp lifters since rebuilding the motor, and the constant tick will not go away. Guess its time to make the switch to Johnson. Frustrating to say the least to have to continually tear the top end apart and adjust the rockers time and time again!

as long as they're rotating they won't break anything. another point here; these newer aggressive hydraulic cams will have some clatter due to the fast closing ramps; but not a constant tick like one or two tappets aren't pumping up.

 

[747mopar]

all this is a perfect excuse to go to solid lifters. the solids will idle better and make more power thru the whole power band.

Exactly! I'm done with hydraulic lifters, it's really sad though that it's come to the point where to be confident in your build you have to steer clear of hydraulics because knowbody can get right what once was a reliable part! Sickning if you ask me but on the plus side I love my solid lift cam.

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I'm on my 2nd set of comp lifters since rebuilding the motor, and the constant tick will not go away. Guess its time to make the switch to Johnson. Frustrating to say the least to have to continually tear the top end apart and adjust the rockers time and time again!

Your flirting with disaster replacing lifters after the cam is broken in, the texture on the new cam aids break in and gets the lifters seated properly which is why I had Comp send me a whole new cam and lifters.

 

[65 Coronet]

Exactly! I'm done with hydraulic lifters, it's really sad though that it's come to the point where to be confident in your build you have to steer clear of hydraulics because knowbody can get right what once was a reliable part! Sickning if you ask me but on the plus side I love my solid lift cam.

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Your flirting with disaster replacing lifters after the cam is broken in, the texture on the new cam aids break in and gets the lifters seated properly which is why I had Comp send me a whole new cam and lifters.

I agree. Looking to go with a Hughes cam and do away with the COMP cam and start from scratch. I really don't have any other choice right now.

 

[lewtot184]

something to look at is the amount of lifter preload. all the original tappets and the newer ones have .200"+ plunger travel in the tappet. with this long travel the tappets will need .060"-.090" of preload. this means with a 3/8"-24 thread adjuster the adjuster will need to be turned in at least 1 1/2 turns. trying to set a .020"-.040" preload may not work well with some tappets. there were some tappets made some years back that only had .100" plunger travel but i think they have been long gone for years. it's also my understanding that comp is using johnson tappets. there may be a quality control issue. personally i think people ask too much of a hydraulic tappet. they were never meant to do what folks are doing with them.