Something is hitting!!!

Guero

Active Member
Oct 11, 2005
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Ok so i i drive the beast(lol), and i pass arond 3500 rpm, something starts to hit, sounds like from the back of the driver side valve colver. Im thinking a rocker nut is coming loose, and is loose enough just to hit when i reach that rpm. Any thoughts from you guys? im gonna retorque the heads, since i have to take of the top intake to see into the valve covers, just wanted your 02 cents if im right.
 
I would think that if you had a loose rocker nut, you'd be hearing a loud clicking noise at idle as well, not only hitting at higher rpm's. Do you hear it if you put it in neutral and rev it, or is it only when the engine is under load, say when flooring it in third gear? Either way, I'm sure you'll find something out of whack when you take 'er apart
 
it doesn't do it it at idle, unless i just put it under load, then it does it under load then in idle for a few seconds. went to my friend who is an mechanic, and he said the oil might be tear it up sooner since it does it at higher rpm, he said i might need to which to 20 50,
 
1TallMF said:
I would think that if you had a loose rocker nut, you'd be hearing a loud clicking noise at idle as well, not only hitting at higher rpm's.
But does the rocker travel its whole distance when just shifting below1700rpm? If it doesn't and travels the whole distance only when under load. maybe its just loose enough to where it hits the valve cover:shrug: :shrug: what else could it be? cant be the spring, valve or pushrod, cuz then i would hear it all the time.
 
Something's got me thinking perhapse sufficient oil is not getting though one of the lifters, and hence to the pushrod and rocker arm. I'd try maybe a bottle of "oil flush", to get rid of any gunk that might be stuck in a lifter, then drain the oil and run something a bit thicker, maybe 10W40, or 20W50 if its REALLY bad, or even some of that Lucas stuff, seems to work quite well. Perhapse someone else will have a better idea of what might be causing it :shrug:
 
A heavier weight oil isn't going to fix the problem. It either sounds like an exhaust leak which isn't that bad so you only really hear it under load. It could be your pipe from head to head aswell. I'd search around with a vacuum tube for a leak first. If you are 100% sure it is a rocker/lifter or internal. DO NOT drive the car. Fix it first.