I have had two rocker arms break on me. They are different ones, on the passenger side being the very 1st one and the other one was the 5th one from the front.
I simply replaced them with new ones and readjusted them.
It is a 307 engine that is stock with an Edelbrock Perf. RPM and a Holley 600 cfm vac. secondary's along with an HEI igntion.
The engine seems to be running great other than these rocker arms breaking.
Is it that since they are possibly original arms that they are finally failing, do all the valves just maybe need readjusting, or is there somer other issue doing this?
Do I maybe need new lifters, pushrods, and rocker arms???
Any help is greatly appreciated.

If it is an all stock 307 that has never been rebuilt, I would assume that it has quite a few miles on it. I would put it more into the category of normal part failure/life expectancy. Especially if nothing else has been done to the engine other than carb/manifold add ons.

If it were my engine, I would spend a few bucks and just replace all of the rockers. Stock rockers can't be to expensive.

Yup,agree,if the rockers were old/used being worn out would likely be the issue.

Id replace the rest of the rockers ASAP because some times when the rockers break and when they come off they can hit the valve spring retainer poping the keepers lose resulting in dropping a valve and killing the motor elquickooo!!!

scott

Thanks guys for the input. At 3.99 a rocker it's gonna be a done deal.

Thanks guys for the input. At 3.99 a rocker, it's a done deal.

One more thing,dont forget to check both ends of pushrods for wear too esp on rocker end and reaplce any that look worn while your at it.

Use some kind of assembly lube ,Lucas new TB Zinc breakin lube,stp in blue container, or at the very least pour some oil onto the rockers and rocker balls prior to tightening adj nuts for valve adj so they dont run dry at startup and for the small breakin they will go thru.

Scott