post #1 of Old 12-27-2012, 07:50 AM Thread Starter
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1999 TJ Wrangler 
Join Date: May 2012
Location: San Diego
Posts: 4
Rockers/pushrod tapping at high rpm??

I recently built a 4.6 stroker out of my 4.0. everything runs great, but around 3000 rpm under load, i get a random tapping noise in the engine. it isnt a knock, and i thought it was the rods on the rockers. i pulled the valve cover off and checked everything out. there is flow through the pushrods and no severe markings on the rockers. this only happens after the eninge is at operating temperature and the oil is warm. i use castrol synthetic 5w-30 in my motor. i think the oil might be too light for the engine. i have 20lbs of pressure at idle, and at 2000rpm im at 40-41lbs. would moving to a 40 weight oil help with this? i know it isnt damaging anything yet, but the wear on the rockers could lead to premature failure. i also just moved to upstate NY and i dont want to go too heavy. would a lucas oil additive be a better choice? thanks for the help guys, I need all i can get!


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post #2 of Old 12-27-2012, 01:11 PM
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1997 ZJ 
Join Date: Dec 2006
Posts: 19,793
Check for camshaft wear.

'97 zj 5.2, some stuff, some other suff, and some things that even work sometimes.

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post #3 of Old 01-01-2013, 11:43 PM
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Join Date: May 2010
Location: british columbia ca
Posts: 518
sounds more like pre-ignition,try some premium fuel.
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