Push rods are sticking through the rocker arm

[CS99]

I have a comp cams hyd. roller. Today while driving, the engine started misssing, so I pulled off the drivers side valve cover and cylinder 3 had both pushrods sticking through the rocker arms!!! All other rocker arms are fine. I am wanting to know if this has happened to anyone else? I am going to order a set of roller rockers tomorrow.

 

[Boost231]

wow. please post pics. o while your at it if you would be so kind to order me a set of roller rockers as well that would be swell.

 

[CS99]

heres the pic

 

[Boost231]

wow. i have never seen that but im sure it has happend before? what spring pressure are you running? i also see your running a roller cam so im guessing with the high seat pressure and the stock rockers it just couldnt hold up.

 

[REBAL T]

Happen to me 3 different times before I changed over to rolller rockers. Were you pushing the car hard when it happen. That's what caused mine to brake.

 

[Rodney87GN]

Hmm, after seeing that I'm thinking of going with roller rockers after all. I'm getting all the parts for my motor rebuild which includes a roller cam....

I was gonna go with HD shafts with new stock rocker arms to save a little money but I might reconsider.

 

[jhanson1750]

I've seen this with high spring pressures and low oil flow/pressure. Causes the pushrods to "dig" into the rocker arm. Good luck with the car Jon Hanson

 

[CS99]

Thanks for all the replies. -cs

 

[86bluet]

cool paper weight

Have seen this when the valve guides were bad or the valve was bent slightly hope this is the worst case

 

[turbofabricator]

I smell detonation. Usually, it just bends the push rod, though. I have not seen that with a hyd. roller and stock rockers. Did you pre-lube the push rod cup prior to install? Might have failed at start-up. Lube EVERY piece with good assy. lube on installation.

 

[Boost231]

i would think with the high spring pressure and running a roller caused this. stock rockers arent made to handle this type of pressure

 

[PEACHS]

Incorrect pushrod length and valve lash.

 

[TT/Ameasap]

Incorrect pushrod length and valve lash.

Thats what im thinking.

 

[bison]

Thats what im thinking.

Me too. Geometry problems will do this every time if its off enough. Ive seen it do it to rollers too. Especially on chevys with too long of a pushrod.

 

[johnnyttype]

I smell detonation. Usually, it just bends the push rod, though. I have not seen that with a hyd. roller and stock rockers. Did you pre-lube the push rod cup prior to install? Might have failed at start-up. Lube EVERY piece with good assy. lube on installation.

can detonation cause both #3's to be crippled? just wonderin, i do find it strange that it was common to a cylinder.

CS99, atleast u know u have some strong pushrods!!! my friends 350 put a pushrod through a rocker but his pushrod was shaped more like a pretzel!

 

[Red Regal T]

Had this happen on my dark red T a few months ago. Only one pushrod. The car is stock, original unopened. I think it's caused by an inferior, poorly casted, rocker arm and/or old age. Lasted 20 years, though.

 

[PEACHS]

Weak casting can cause this to occur, i know of a few low mileage GNs cranks snapping in two from normal driving. Guess lack of oil and tight clearences can cause this. An earlier post of a Block missing a large section of the lifter valley was missing. Also engine blocks breaking in two from 20-25# of boost sometimes these things happen...

 

[turbofabricator]

I've seen BOTH push rods on #3 cyl. bent into an "S" shape. He did detonate it REAL bad, though. The piston alspo had some edges missing, and a crack in the main webbing, and two main caps broken. The push rods were the least of his worries. Running your alcohol tank dry is a VERY bad thing.

 

[PEACHS]

That is severe damage, did the timing chain break by chance? Almost sounds like the piston contacted the both valves. How many pounds of boost were on the motor? Sorry to hear this

 

[bison]

That is severe damage, did the timing chain break by chance? Almost sounds like the piston contacted the both valves. How many pounds of boost were on the motor? Sorry to hear this

The amount of boost is irrelevant. It detonated really bad. It could happen at 19 psi. Id bet the connecting rods were tweaked also and the rod bearing shells pounded out. Fwiw the stock rocker arms are stamped steel and are actually fairly strong just because they are stamped. There has to be wear there before the pushrod will go through the arm. The stock rocker shafts are weaker than the arms and fasteners that hold them in place.