I just installed a Comp cams k kit in a newly rebuilt 400. It was the xtreme energy 268 cam kit. The lifters are noisy still...after talking to their help line they told me that it should quiet down after break in. Well it is making me nervous since I have ran it for a couple of hours now and its still quite noisy. I took off the rocker cover and could remove a pushrod by hand. Has anyone else had this problem and how can I correct it short of removing them and sending them back. This rebuild has gone smooth except for the Comp Cams stuff. The cam was chewing up distributor gears. A bronze MSD may have cured that.

 

somethings wrong! don't run it any more until you find out why you are able to "remove a pushrod by hand". are you able to remove more than one? all of them if you turn the engine by hand to rotate the cam off the high spots? do you have an oil pressure gauge hooked up? what was the pressure when running? i'd drain the oil into a clean pan and check for silver metal particles first.

 

if your pushrods are that loose you don't have the preload on the lifters and they will be noisy. by the soiunds of it your pushrods are too short (assuming you have none adjustable valve train) and you don't want to keep running it like that. I am not for sure but I believe the 268 xtreme cam is ground on a smaller base circle than stock and will require either a adjutable setup or longer pushrods or if you have shims under the rockers you mighthave to remove them, but get the lash setup correctly.
What concerns me more is eating dist gears if you chewing up iron gears the bronze isn't gonna last as it's even softer and used on steel roller cams.

 

you have the wrong push rods. you need the correct length.

 

I have checked all the pushrods on the left side and they are all very loose. The pushrods are stock length. The heads were milled .010 and the difference taken off the top of the valves by the machine shop. I can look down into the motor and see that the inside of the lifters are stuck or not at the top. We are talking a good 1/4" difference for me to just move the rod over and lift it out.

 

Check your engine oil for metal particles.

I don't want to scare you but I had a similar problem with my engine. My machine shop used a Comp Cams XE256H kit in my rebuild. The first run on the dyno was great - and then things went bad, real bad, real quick. After a lot of head scratching, they ended up disassembling my motor and found that one of the lifters had completely sheered off on the bottom. Needless to say they had to tear the entire motor apart and re-replace everything.

They contacted Comp Cams about the problem and Comp Cams said they have had more cam and lifter failures in the last 2 years than they've had in the previous 20. Comp Cams attributes the cam failure to the lack of zinc in gasoline engine motor oil and suggested using diesel engine oil during the break-in period. I've also heard there was a batch of bad lifters a year or so back.

The good news is everything was fixed and I couldn't be happier with the Xtreme Energy cam. Good luck!

 

It happened again. The cam and lifters went bad. It has to be the oil...I hope. I am at a loss if it happen's anymore. Has anyone else heard of this problem with Crane or other name brands besides Comp Cams?

 

what kind of oil did you use both times? i picked up a gallon of Rotella and a big bottle of snake oil called hyper lube. i've heard of using EOS (engine oil supplement) available at certain dealers parts dept's too. i'm getting ready to fire up a 268H myself.

 

What kind of spring pressure are you running? You may have to remove the inner soring for the break in. We have engines in a circle track application, solid lifter cam and .650" lift. they have some pretty high spring pressures. I am willing to bet Comps latest failure rate is possibley because of the rate of lift gets higher all the time. So the engine builder needs to be aware of this.

 

i don't know what the problem is exactly, but i would put my money on comps cams. i have used them for years with no problems. but in the last two months i have seen 5 comp cams go flat in a matter of hours and one lasted almost a week. and i now one of them was a comp 268h. i don't think there is a problem with comps lifters because one of the engines we used cranes lifters and the comp cam went flat again, twice in the same motor. now on the third total rebuild with a crane cam it's still running strong. crane and lunati fixed them all. i'm not saying all this to try and down comp cams i have relied on them for years with a lot of luck. so i hope this is a issue they get worked out soon for all of us. it's hard enuff to try and save for one rebuild and then have to turn around and do it again. it gets real frustrating the second time because a cam went flat for no reason, i now. good luck and i hope it all works out for you. latter..

 

Oh crap! I have a comp cams xe262 k-kit still in the box! Maybe I'll leave it there until someone figures this out.

 

I heard from the guy who rebuilt my trany the same story on comp cams. He builds tranies for alot of the local race guys. He's not saying that comps doesn't have good grind numbers, but they have a higher failure rate, and he prefers crower, or crane. funny cause I had never heard that before, and now I'm hearing it here. This site rocks.

 

The k-kit came with the springs that have a inner dampener. I called Comp Cams and they told me that it isn't a dual spring so you shouldn't have to remove it for break in. I used Pennzoil 10w-40 then Mobil 1 the second time.

 

When you looked down into the engine and saw that the lifters were collapsed, was that with the pushrods loose? Did you prime the oiling system until you got a pressure reading before you fired it up? Ifnot, you may have damaged the lifters, and/ or bent the pushrods. BTW , I would not use Mobil 1 on a new rebuild until the rings are seated and everything is functioning properly. At least 1500 miles, use conventional motor oil ( I like Havoline) until that point. Check the oil and lube forum on this site.

 

Well I agree up to a point..Prime your system before fire and run rottela Diesel motor oil intil the break in is done..It has the highest content of zinc ..greta for cam break in..

Russ