Rocker Failure

[g356gear]

I went to take the car for a spin today and enjoy the weather a little. I warmed her up and then proceeded down the road. About 1/4 mile into the trip I noticed the sound of an exhaust leak or puffing from the driver side exhaust. A few seconds later I start to hear a light tapping from the motor. Instantly I pull it over, shut it off, and pop the hood. Everything looks OK. Start it up and I get a loud tapping from driver side #1 cylinder. Pull the spark lead and it stops. Great....something let loose in the new motor. Managed to limp it home and pull the valve cover and this is what I found....



None of the parts of the rocker actually broke off....just spread like an orange opening up. I spotted a few very fine particles but nothing major. So now I would like to find a good quality upgrade rocker set that I can still fit under my stock 396 valve covers. Any ideas?

[Lowend]

I've seen that kind of failure before. Unless you recently changed a cam I would chalk it up to bad casting

Comp Cams Pro Magnums are the best low-pro rockers I have found

[g356gear]

Thanks or the tip. I actually picked up a set of those today. I looked at the Scorpions but for the few extra dollars, why mess around.

[Vegas69]

Roller all the way. That stock crap isn't worth it in a performance application.

[g356gear]

Well, I pulled the rest of the valvetrain out this morning and found a few more issues.



I have a bent #2 pushrod and a few are slightly darkened in the centers. Is this discoloration from stress?


#7 exhaust rocker looks to be getting super hot as the oil is burning on the rocker and nut. Any ideas what is going on here? This is the only one that has an issue.



All the other rockers seem to be fine. I don't have any galling on the pushrod tips at all. I noticed the guide plates on the pass side have a little wear but there is nothing really on the pushrods themselves.

[Pro Stock]

With all the parts that you have that are showing heat damage I would check for proper oil flow to the top end of the engine first, pull the distributor first, leave the valve covers off the heads and spin the oil pump with a drill motor and priming driver, you should see a good amount of oil coming through the pushrods and rockers, has anything on the engine been changed such as camshaft, if so was the piston to valve checked ? . Too tight of clearance can cause the pushrod bending. Good luck with your engine, I hope you get it fixed.

PS. I have been running a 502/502 with stock rockers on the dyno and have put close to a thousand (no lie) pulls on it with no problems.

Dale

[TonyHuntimer]

If for some reason the pushrod or the lifter got clogged and stopped delivering oil to the rocker, it could cause one rocker to overheat and gall...then get super hot after galling starts.

Was the bent pushrod on the cracked rocker? Was the cracked rocker the same one that was toasted?

Is this in the same Camaro that sat for 20 years and you experienced fuel pump problems?