3rd Gen / L98 Engine Tech 1982 - 1992 Engine Related

Tapping sound from the valve cover

Old Apr 9, 2004 | 01:29 PM
  #1  
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Tapping sound from the valve cover

My car is making a tapping sound. Im thinking it might be a pushrod. Before I take the valve cover off I was just wondering what else I should look for? its a 350 Crate TPI if that matters. Also do I need to take off the intake manifold to get a better view? Thanks guys
Old Apr 9, 2004 | 04:38 PM
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could be a rocker arm ,valve, or valve spring as well too. the best way is to take the valve cover off and let the car idle. best to let teh car run and warm up,then take the valve cover off (keeps the RPM down...lower oil pressure...not as much of a mess).

i did this on my car and leaked a couple drops of oil,u might need to get a piece of cardboard the length of the head and about 6 inches high to block the oil from coming over the side of the head while its running.

good luck
Old Apr 9, 2004 | 05:34 PM
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It could be a bad ,or sticky lifter also. Use some Marvel Mystery Oil for a week and see if that helps before you go tearing down the engine. This will help clean in inside of the motor also,so if you do have to tear it down it will be cleaner. MMO works wonders always try it first.
Old Apr 9, 2004 | 07:42 PM
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I agree on the Marvel Mystery Oil....that is great stuff. I also swear by Sea-Foam for cleaning injection systems and intakes.
Old Apr 9, 2004 | 07:45 PM
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never once heard a bad thing about the marvel oil. all the old timers swear by it, as do i

i also agree with the above posts about the rockers/springs/rods. it must be one of the 3. maybe more

and no, you do not need to take of the manifold. this is where the centerbolts come in handy. other then this task, they are terrible
Old Apr 9, 2004 | 09:05 PM
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To clean the inside of the engine, I drain out a quart of oil or two and replace it with ATF, run for a couple hundred miles and drain it out. Fresh good oil will replace it.
Old Apr 10, 2004 | 12:42 PM
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I had a nasty tapping coming for my valve cover turned out i had to adjust the valves the nut on one of them backed off causeing it to tap.
Old Apr 10, 2004 | 01:03 PM
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Like dragula said, make sure your lash is set correctly. Also, hows the oil level?
Old Apr 10, 2004 | 11:36 PM
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Better yet, how is the oil pressure?
Old Apr 11, 2004 | 12:50 AM
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And don't go by the stock gauge.....that's not an instrument, it's a trim package.
Old Apr 11, 2004 | 01:04 PM
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The stock gauge is good and should be used as a guide in a pinch. however, to be truely accurate, you need to have a good gauge hooked up to the sensor port and evaluate it now and then.

If your tapping is all over the VCs, I might suspect oil pressure but if you put the screwdriver to your ear and the other end to the VC and find that it is at one spot only, rip off that cover because you might have a broken spring. Ask me how I know.
Old Apr 13, 2004 | 01:21 AM
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Originally posted by aklim
The stock gauge is good and should be used as a guide in a pinch. however, to be truely accurate, you need to have a good gauge hooked up to the sensor port and evaluate it now and then.

If your tapping is all over the VCs, I might suspect oil pressure but if you put the screwdriver to your ear and the other end to the VC and find that it is at one spot only, rip off that cover because you might have a broken spring. Ask me how I know.
Havent had time to get the cover off this weekend. All the smog stuff is in the way...HAHAH.....I used a piece of exhaust pipe and moved it around to see where the noise is most and it seems like it is real loud above the VC's like right in the intake part. Oil is good. Thanks for the help like always guys.
Old Apr 13, 2004 | 02:28 AM
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I don't think there are moving parts in the plenum so I would say you need the VC off and touch the screwdriver on each rocker stud.
Old Apr 13, 2004 | 12:08 PM
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A long handled driver is a little more precise than an exhaust pipe. Sounds like you need to rip off the VC and be prepared for the worst. Have a set of gaskets ready too.
Old Apr 13, 2004 | 02:22 PM
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Originally posted by WhiteKid
Havent had time to get the cover off this weekend. All the smog stuff is in the way...HAHAH.....I used a piece of exhaust pipe and moved it around to see where the noise is most and it seems like it is real loud above the VC's like right in the intake part. Oil is good. Thanks for the help like always guys.
That could just be your injectors clicking. Buy yourself a cheap stethoscope at the auto store ,works better than a screw driver or hammer handle.

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