I have two bent back rockers at the valve springs. I'm not sure if the rockers bent back from age or if the pistons hit the valves. I thought maybe the springs are weak and the valves floated for awhile and were smacked. It ticks at cold start then gets quiet at 200 degrees. Anyone have any ideas is this common? Maybe hydro locked at some point.

 

i highly doubt they just bent from age....and i didn't think these were interferance engines i could be wrong...and if a valve floats and a were piston hit it it would bend the valve not the rocker and you would have one hell of a skip not to mention i don't think these hydraulic lifters have the pressure needed to bend the rocker if a valve were to stick. so i would say.. either its not actually bent or someone screwed with it before

 

Well, what I thought was two bent rockers is actually two collapsed lifters! I need to pull the head to remove the lifters, correct?

 

Is there enough room to pull the lifters from the top out of the head or do I need to remove the head?

 

I believe the heads got to come off on the 4.0L. Unless u r already using synthetic motor oil, I'd try a crank case full (oil change) just to see if that would quiet/clean things up a little (synthetic motor oils are heavy on detergents). If it doesn't, then change lifters.

 

the head must come off to replace the lifters and if its in the budjet i recommend new push tube also at least the two where the rockers were bent and new camshaft while your in there if money allows

 

Pour a quart of Marvel Mystery Oil in it and run it for a few hundred miles. That might unstick your lifters if they aren't too badly gunked up. If it does unstick them put in a can of STP to keep them running free.

 

the damage is done if the rocer arms got bent

 

I dumped a quart of oil out and added a container of lucas oil stabilizer, wow what a diff. no more crazy noises and to me it feels a little more ballsy.

 

kool