Mopar Indy 440-1 heads breaking rockers

[Larry G]

All of the sudden this thing is breaking the rockers through the adjuster threads from the shaft up diagonally up through the threads there 1.6 Indy rockers. The car ran all season last year no problems this year we broke two on different cylinders end exhaust #2 and 8 any Ideas.

[Larry Hill]

Maybe there is a service life.

[Jacob Pitt]

I've heard very bad things about the Indy rockers. I run Indy heads on my bracket cars, one being a small block with T&D rockers and the other is a big block with Harland Sharps. I heard the horror stories so never bothered buying the Indy rockers.

[Mike Taylor 3601]

Check spring pressure,they may have got weak
Mike Taylor 3601

[njk53]

If you ran all season with no issue and nothing else has changed, I would agree that the service life of the rocker is at it's end.

[Larry G]

Jacob Pitt how do you like the Harland sharps do you have the ones with the needle bearing for the shaft.

Thanks for the reply's everyone.

[james schaechter]

Originally Posted by Mike Taylor 3601

Check spring pressure,they may have got weak
Mike Taylor 3601

Quality of the Rockers might not be good, who knows, but checking spring pressure is an excellent idea. Bouncing them is no good.

[Mike Taylor 3601]

Maybe rockers, but first place to look is springs,if you break valvetrain most of the time you will find springs are too weak, from worn out and lost pressure or just too weak to start with and has beat on rockers long enough they have started breaking.
Mike Taylor 3601