valvetrain noise please help.
Thread Starter
Instructor
Joined: Oct 2008
Posts: 136
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valvetrain noise please help.
thanks ahead of time for input, here is the problem crank the car in the morning and all lifters are clattering for a few seconds until thy get pumped up then drive down the road a couple of miles and a loud tap sets in, i pulled over and let the car come back down to idle after a minute or so it stopped, you can still here slight noise at idle, all this started after i put lg g5x3 camshaft in the car it is a 98 model with 76,000 on the ticker, 5.3 heads that have not been milled, double springs that are good to .650, with a 7.400 pushrod, the car has had about 100 miles on put on it since heads and cam, could there be trash in one of the lifters causing it to bleed off, or is it time to tear back down and replace the lifters. What are the chances of this lifter getting back on duty.
Pro
Joined: May 2004
Posts: 551
Likes: 19
From: Morgantown WV
thanks ahead of time for input, here is the problem crank the car in the morning and all lifters are clattering for a few seconds until thy get pumped up then drive down the road a couple of miles and a loud tap sets in, i pulled over and let the car come back down to idle after a minute or so it stopped, you can still here slight noise at idle, all this started after i put lg g5x3 camshaft in the car it is a 98 model with 76,000 on the ticker, 5.3 heads that have not been milled, double springs that are good to .650, with a 7.400 pushrod, the car has had about 100 miles on put on it since heads and cam, could there be trash in one of the lifters causing it to bleed off, or is it time to tear back down and replace the lifters. What are the chances of this lifter getting back on duty.
Have you checked the torque on the rocker arm hold down nuts?
Racer
Joined: Aug 2008
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Racer
Joined: Jan 2005
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From: Troy MI
are you saying that you measured for proper pushrod length? If not - do that, it is easy to do.
Otherwise, I cannot offer any more assistance - I have the same cam with different heads and do not have that problem.
Otherwise, I cannot offer any more assistance - I have the same cam with different heads and do not have that problem.
Pro
Joined: May 2004
Posts: 551
Likes: 19
From: Morgantown WV
The most common description for valve train noise is that it makes a "sewing machine" sound. This is common for all H/C cars. If your car is making a clattering sound that goes away after start up with a subsequent loud tap.......that is not normal.
Thread Starter
Instructor
Joined: Oct 2008
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the loud tapping after driving a couple miles, then the sudden silence is what bothers me, even after warm up
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Thread Starter
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Team Owner
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From: At the beach in little Rhody
At this point start simple and start cheap (don't throw money at the problem). Was the oil pump changed? Any difference in filter that you are running now vs. before the swap? Any fluctuations in oil pressure that you notice?
Thread Starter
Instructor
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yes i installed a new melling oil pump same filter brand as before, oil pressure runs about 20lbs at warm idle, 40lbs at cruise, 70 at wot.
Melting Slicks
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From: Cedarburg, WI
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I have an EG Whiplash Cam. Its bigger than yours.
I have patroit stage II heads, caddy racing lifters and the same push rods you have. I have lttle or no noise. I can literly hear the valve slam shut at idle.
Thats the only noise that I have.
If I were you I would pull the valve covers off and look carefully at the rockers and make sure you dont have any rockers that puked out the roller bearings. Thats a common issue.
Bill
I have patroit stage II heads, caddy racing lifters and the same push rods you have. I have lttle or no noise. I can literly hear the valve slam shut at idle.
Thats the only noise that I have.If I were you I would pull the valve covers off and look carefully at the rockers and make sure you dont have any rockers that puked out the roller bearings. Thats a common issue.
Bill
Team Owner
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From: At the beach in little Rhody
Do you have access to an adjustable pushrod? Like Bill said, next step would be to remove the valve covers and inspect things (no cost).
Unfortunately, your installer should have recommended new lifters. With 78K miles, a very fast ramp cam of high lift and heavy valve springs is just not a good mix, especially since a new set would have been about $150 at the time and he likely had the lifters out of the car when he put the cam in if the heads were already off the motor.
Unfortunately, your installer should have recommended new lifters. With 78K miles, a very fast ramp cam of high lift and heavy valve springs is just not a good mix, especially since a new set would have been about $150 at the time and he likely had the lifters out of the car when he put the cam in if the heads were already off the motor.
