bent a pushrod

[ocbaud]

yeah, i'm still here for a little while longer
wont know about the jetta till about thursday.

anways, my rocker arms have been becoming loose after only hours of driving the truck after adjusting them. i've adjusted them 4 times in the past 3 days and the same ones keep getting loose. well, this happened today:

yes, those are hardened pushrods....

so, what would cause this to happen? i didnt have them over adjusted, and when i pulled the valve covers the past couple days, there were 2 rockers loose and were makign loud loud noises. so today i had to fix it after driving for 10 minutes and finally made it halfway home before it started again, got home, let it cool, checked it out and thats what i found.
no place is open right now that sells hardended pushrods either

[gchemist]

You have a serious mechnical problem. You need to go through the valve train before you destroy engine parts!!! Especially pistons and valves.
Man you seem to have some serious problems with your truck. I should take off your hands to drive it like I drive mine.

[Trimman]

what ratio rockers are you useing?

[Nolowrider]

The only thing I can really think of that would cause the rocker to back off is, a bad stud or maybe the nut. Is you studs threaded in or pressed in? Maybe get a cheap rod and new nut and try it.

[86 GMG]

do you think that your timing chain has jumped a tooth? taht could cause this i think

[Nolowrider]

Yea, a jumped timming chain would do that, but it would usally be more than one rod bent. Plus, he said he had trouble with the rockers backing off.

[hotrodhomi]

What if one of the lifters were stuck. I would try to grab that sucker with a magnet and see if it moves freely.

[Moostifer]

had the same problem a few years back on a fresh rebuild... at first I thought it was the nut backing off, so I put Locktite on it and marked the nut & stud with a paint marker so I could tell if it was backing off. Two days later, it was tapping again and the nut hadn't moved. I was like "W.T.F. ? so I pulled the intake and checked the lifter, it was fine, so now what?.... long story,short, the pressed in stud was slowly pulling out, I put a screw-in stud in and never had another problem.

[ocbaud]

yeah, these are already nice screw in studs. but they are harland sharp roller rockers, which i've heard some complaints about this brand coming loose.

how would i know if it jumped a tooth? when i was adjusting the other ones, it looked like the balancer was about 5 degrees off from where it used to be at tdc(my balancer is degreed)

[Moostifer]

only way to tell for sure... take the timing cover off, pull the plugs, and crank the motor over by hand and make sure your timing marks line up.

a weak valve spring might cause this problem...

[Nolowrider]

Maybe it did jump a tooth. Sort of sounds like it now. Like Moostifer said, yank the timming cover off and take a look. Kind of a PITA though to get to it just to take a look. But, might as well replace the set while you are in there.

[jermasaurus]

I know whats wrong..... The truck doesn't want to be sold.

[ocbaud]

FU CK!
i cant get the lifter out to check it with out taking the intake off damnit i have to much work to do to this truck. plus i have class tommrow and aevery damn day. god i cant wait to get this thing off my hands.

and yes, the truck is pissed off cause i'm getting rid of it.

[Tom]

The truck dosen't care your getting rid of it, its the fact your getting a VW that pisses it off. At least your not getting a mitsubishi.

I would say either the rocker arm nuts or else the cam/lifter is the culprit. Either way the truck is not operable right now and needs to be parked.

[phantom dually]

Originally Posted by Tom

The truck dosen't care your getting rid of it, its the fact your getting a VW that pisses it off. At least your not getting a mitsubishi.

I would say either the rocker arm nuts or else the cam/lifter is the culprit. Either way the truck is not operable right now and needs to be parked.

Hell him getting a VW pisses me off!! Traitor!!! Thats a womens car right?? JK!!

[NeCrOmAnCeR]

This may be a little off-topic, but did you find out what was causing the knocking noise a few weeks ago? May have floated a valve and bent it, causing the piston to hit the valve while held open by the cam, thus causing the bent pushrod. (.490 lift is border line for needing to check piston to valve clearance)

As far as the rockers backing off, is a common complaint it seems with the Harland-Sharp rockers. As for yours needing constant adjustment the last few days, I'd say that the push rod bend was getting worse, every time you adjusted it would bend a little more.

Hardened pushrods do not prevent bending, only prevent the rod from galling (SP) on the guide plate. Checking for pulled/streched rocker studs is as easy as placing a straight edge on top of the studs (front to back) all the studs should be at the same height, a longer one needs to be checked out.

You also need to check the rocker arm geometry real close before buttoning it back together.

[fastwillie 696969]

are you using poly locks on the roller rocker arms ?

[Moostifer]

have you concidered that a lobe on the cam may have gone flat? that would explain having to adjust your rocker... and the bent pushrod.