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Discussion Starter #1
Hi Friends

I have that tappety sound from under the valve cover. I wonder if I take out the valve cover and feel for loose rocker arms would I have to rotate the engine to TDC for each cylinder to guess looseness if I have found a stuck or damaged lifter.

The compression test found cylinders ranging from 90 psi to 120 psi and one cylinder at 150 psi !
 

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I used KREEN. The best snake oil ever milked from a reptile. About 8oz quietened my lifters in about a two minutes or less. Made my oil pressure gauge actually move like it should again.

Illegal for sale in California so it has that going for it.
Engine Cleaners
 

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Did that "tappety sound" just start? Did it start after some other work?

Have you tried "the usual fixes" (aka "Marvel Mystery Oil/ATF/Sea Foam)?

I'd pull the covers and put a straight edge across the studs to make sure no have pulled out, pull and inspect all the rockers, fulcrums/balls and pushrods (remember to keep them in order) and if THEY'RE all okay I think as long as I was in that far I'd check stemp to guide clearance and replace the valve stem seals, finishing up by pulling the intake, checking camshaft lobe lift and, if THAT'S okay, throwing a set of lifters at it. Remember to do a break-in, just like you installed a new cam.
 

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Yep.. ZRAY is right....Replace the whole set... Some people say that you MUST replace the CAM as well. That is total BS. You ONLY have to do that if there is heavy wear on the existing Lifters. If the old lifters are laser straight and are not "Concave" on the ends...and show no major wear, Just put the new lifters in with some good cam lube on the ends and you're good to go for the next 50,000 miles at least... Mind you this is on a "daily driver" not on a "Race Engine" or High Performance engine....For that, I would change the Cam as well.

:eek:)

Tony K.
 

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Make sure each lifter is required to its original location. Mixing up used lifters is a big no-no. There's nothing wrong with taking it apart to check things. I did it when my engine had 120000 miles and it was in great shape. Just cleaned off a few minor deposits and verified it was OK.
 

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If the old lifters are laser straight and are not "Concave" on the ends...and show no major wear,
Lifters are SUPPOSED to be slightly concave and off-center on the lobe to cause them to rotate. It'd be "bad" if they were flat or CONVEX.
 

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Discussion Starter #10

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Discussion Starter #11
How is the oil pressure? I ask because years ago my 351W had ticking lifters. I installed new lifters and they continued to tick. The problem was the cam bearings were worn which created a low oil pressure situation in the valve train.
Pressure is normal position on the gauge.

The engine has been stored for thirty years, I have been driving it no problems last few weeks.

66,000 miles on engine which cant be original. I purchased the car in 1986.
 

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Discussion Starter #12
Did that "tappety sound" just start? Did it start after some other work?

Have you tried "the usual fixes" (aka "Marvel Mystery Oil/ATF/Sea Foam)?

I'd pull the covers and put a straight edge across the studs to make sure no have pulled out, pull and inspect all the rockers, fulcrums/balls and pushrods (remember to keep them in order) and if THEY'RE all okay I think as long as I was in that far I'd check stemp to guide clearance and replace the valve stem seals, finishing up by pulling the intake, checking camshaft lobe lift and, if THAT'S okay, throwing a set of lifters at it. Remember to do a break-in, just like you installed a new cam.
And all that can be done in one weekend? OMG. MMO and sea foam now. Thinking about ATF in the oil and idle for an hour. Then change the oil. But when I get the covers off. If I do a running valve lash adjustment and no success on the noise. hmm ..........then how can tell its actually a lifter?
 

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The problem was the cam bearings were worn which created a low oil pressure situation in the valve train.
How often do cam bearings wear? I am no expert by any means but I thought they very rarely wear out? Just trying to educate myself.
 
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