Thread: valves tapping

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Have a 350 with a Magnum 292 camshaft. The engine has 1,000 miles on it. All of a sudden a couple of the lifters started tapping fairly loud. Tried adjusting the lifters but no success. can't stop the tapping. Is it possible a couple of lifters have failed ? Confused!

Sounds like lifter failure to me.

take the valve covers off and start it. you should be able to see some rocker not moving as much as the others.. at least it worked for me

Make sure it is not an exhaust manifold leak you are hearing - this too often sounds like rocker ticking from inside the car.

A lack of oil pressure might be your problem. Maybe your oil pick-up has fallen off. Or maybe one of the oil gallery plugs has lossened up.

If you were to remove the valve covers and then start it up, you would soon know if the oil is pressured to the top.

hopefully, it is a header gasket leak.....if its not and it is in fact a failed lifter, dont run it.....i would also pull the cam out and check to see if you have wiped a lobe.....i have in the past had to replace header gaskets more often than i liked to....they go with out warning......and sound like a collapsed lifter.....these were new lifters right.......

Watch out for all that oil !! Before you start it with the valve cover off look and see if the stud has pulled out ( if you have screw in studs disregard) I you have made a correct adjustment cold ( screw down to zero lash then a 1/4 turn more) you should be close. if you have good oil spray out of the push rods then use a 1/2 rubber hose for the followingPut One end to your ear and the other to the suspected rocker. You should hear a tap if the problem is there. A tap sound may be the exhaust as listed above , but a sticky valve in the valve guide will also do it.