Another rocker arm noise question

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Jul 12, 2016 | 05:51 PM

CaseyJones

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Melting Slicks

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From: McGrady NC

St. Jude Donor '15-'16

Another rocker arm noise question

I had all the springs replaced while the engine was down to fix a dropped valve a couple of months ago. Now I've noticed that I seem to be getting some rocker arm noise as I accelerate. If I go slow and steady up to speed, things seem pretty quiet. However, if I buzz it up through the gears, it sounds like the lash has opened up on some of the rockers and I get a tapping or ticking noise. I'm getting ready to pull the valve covers and take a look but I'm curious to know of anything in particular to look for on a cold engine.

Jul 12, 2016 | 08:52 PM

StingrayRebel

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were the pushrods replaced as well?... if not were they inspected to make sure none were bent before reinstalling the rockers?

Jul 12, 2016 | 08:55 PM

billla

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From: Seattle WA

St. Jude Donor '14

If the installed height of the spring wasn't exactly the same as stock, you have a problem.

Jul 12, 2016 | 09:23 PM

vettenuts

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From: At the beach in little Rhody

How did you drop a valve? Losing control of the valve train can damage the lifter/cam lobe interface.

Jul 12, 2016 | 10:45 PM

CaseyJones

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Melting Slicks

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From: McGrady NC

St. Jude Donor '15-'16

Broke a valve spring and it let the valve drop enough to let the piston break off the head and jam it sideways into the valve pocket. The rockers and pushrods for that cylinder were replaced and a new head was installed. All the springs were replaced with GM's latest replacement for LS6 engines. The GM mechanic said that the cam looked fine or it would have been replaced as well.

Jul 13, 2016 | 07:31 AM

vettenuts

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From: At the beach in little Rhody

If you pull the valve covers, check for rockers that may have lost needle bearings.

Jul 13, 2016 | 10:26 AM

CaseyJones

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From: McGrady NC

St. Jude Donor '15-'16

Good thought. Forgot about that.

Jul 13, 2016 | 10:49 AM

Bill Curlee

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From: Anthony TX

CI 6,7,8,9,11 Vet

St. Jude Donor '08

Quote:

Originally Posted by vettenuts

If you pull the valve covers, check for rockers that may have lost needle bearings.

Also check the valve rocker pedestal (thing that the rockers sit on) and make sure that it is not worn. If the rocker is not sitting straight on the valve, that pedestal saddle could be an issue. I've seen a few that were quite worn.