: valvetrain noise
sic7camaro Feb 19th, 10, 11:38 AM after i installed a cam and lifters.first i didnt adjust the rockers right.well i adjusted to where the rod bearly drag but didnt give it a 1/4 or 1/2 turn after.it didnt make noise at first till a couple miles.i did give it a half turn after i heard the noise but still there.it seems like it coming from passenger side.then again it sounds like a calapsed lifter.could it be a lifter?
440sixpack Feb 19th, 10, 04:52 PM It can always be a lifter , if it's hydraulic. I'm going to guess you are running hydraulic lifters, did you break the new cam in right and how many miles are on it? chances are you need to adjust your valves again but it's hard to say in an over the internet diagnosis.
justincat Feb 19th, 10, 06:40 PM Its a strange thing but when your motor warms up your lifters get looser. So if its cold and there is no knocking, and there is knocking when its warm your probly still a little loose. Some times it takes 3/4 turn. Did you do anything else with the cam swap(exhaust)? Like 440 said, did it do this right after the swap or later on?
JimM Feb 19th, 10, 06:41 PM Could be a few things. replacement "factory style" rocker nuts could be a loose fit and working loose.
Your cam could be going flat.
I really really doubt a collapsed lifter is the problem, it just doesn't happen often. It's not 1961, and we have learned to trust our "juice" lifters.
First things first is to determine which one(s) it is. Easiest while it's running. Get her warm so she'll idle slow and smooth (so as not to make a big mess) pull a valve cover crank her up, and run down the lifter, find out which one is loose and how much.
Write it down.
Adjust em til they are quiet and note how much you got to turn it to get it that way.
If any nuts feel loose replace them now
Drive it. If it gets loud again, do it all again. If the same one(s) are getting loose, you gotta go inside, you're probably loosing the cam.
justincat Feb 19th, 10, 06:44 PM thats what I was trying to say:hurray:
sic7camaro Feb 19th, 10, 06:45 PM other then the noise.it runs fine no problems,yes its hydraulic cc 280h.ill get a vid of the sound in the morning.less then 800 miles.if its a lifter can i use the ones that i took out when i replaced with new ones for now to see if thats the problem?
Steiner Feb 19th, 10, 06:53 PM if its a lifter can i use the ones that i took out when i replaced with new ones for now to see if thats the problem?
No. They have a wear pattern from your old cam and will eat up the new one in short order.
I can never get the lifters right just going by feel on the pushrod. I use a 0.005" feeler gauge between the rocker and valve stem, tighten the nut by hand while sliding the feeler gauge in and out until there is a slight drag, then go a half turn. No noise on mine.
justincat Feb 19th, 10, 06:56 PM Is i just a minor taping sound? I would think its just loose. Take off your valve cover and get a short hose, and put your ear on one end and put the other end on your rockers intill you find with one it is. Tighten it another 1/4 and see if it stops. If so I would turn the rest 1/4 turn and go from there.
sic7camaro Feb 19th, 10, 06:59 PM doesnt make noise while driving just on idle.i have sportsman 2 heads with harland sharp 1.6 rockers w poly locks.it made thenoise a couple miles into the new cam
Steiner Feb 19th, 10, 07:03 PM How's your oil pressure and what weight and brand do you use?
sic7camaro Feb 19th, 10, 07:04 PM Is i just a minor taping sound? I would think its just loose. Take off your valve cover and get a short hose, and put your ear on one end and put the other end on your rockers intill you find with one it is. Tighten it another 1/4 and see if it stops. If so I would turn the rest 1/4 turn and go from there.
yes minor taping.ill give it a 1/4 turn and see what happens in the morning
sic7camaro Feb 19th, 10, 07:10 PM How's your oil pressure and what weight and brand do you use?oil pressure is ok then it drops to alittle over 30,castrol 20/50
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