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?

I can't say that I've ever experienced a rocker arm failure at that point!....Typically occurs at the pushrod cup!.....I'm just trying to figure out how or why this happened, lack of oil?....lack of long slot?.....I recently purchased a set of Summits factory high performance stamped steel rockers for my mouse, no probs!

What's your open valve spring pressure?

As well as seat and installed heights and so forth.....

Lift spec's of the cam, too..

pdq67

What are the specs on the cam and springs? I would say there was too much lift and/or spring pressure for those rockers.

I bet those are chinese!

I used to break intake rockers just like that in my first car. would be driving down the road and have it pop back through the carb! I was told to put a new rocker on the exhaust and use the exhaust rocker to replace the intake.
Problem was galling. The rocker balls weren't getting enough oil due to a hi volume oil pump squirting the oil past the rocker ball!
I run Scorpion rollers now. But have also switched to a standard pump for all my engines.

The car is running a higher lift hydraulic cam set-up. Only about 350 miles on the motor. Everything is getting lot's of oil, good pressure on the gauge and everything was well lubed when I pulled the valve cover. I think I will just swap out to a roller rocker set-up and be done with it. Any recommendations for a good drop-in set of roller rockers?

FYI...these are the stock rockers from 1969.

Hard to tell from your picture, but I bet the slot in the rocker isn't long enough if it is the stock rocker and you are running a larger cam. Look at the rocker stud and see if you see a mark where the end of the slot was hitting the stud ?

X2

Well then that's your problem!.....Any BBC running a cam with .500" lift or more will require long slot rockers!

They are selling full roller rockers DIRT cheap now... may wanna look into a set, or at least replace all of the old ones from '69.

CC has come right out and said that their lost wax cast process steel stock ball type Magnum roller tip rockers are only good to right at 350 pounds at lift so go from there.

We can now buy stock type gold colored one's that are plated w/ I want to say TiN or whatever that will go up to darn near 400 pounds before galling happens.

And right, the short slot may be pinching the stud so definitely check your studs too for any sort of grooves!

pdq67

I ran a Junk Yard 454 8.5:1 for years with a 750DP on an RPM, Headers and Crane 266H-10 M21 to a 4:10. It like to Rev but I had to short shift at 5200 because if I hit 6, I had to reach into the glove box where I kept my Valve train Assemblies. 2 Push Rods, 2 Rockers and 2 sets of Valve Springs with Retainers and Keepers. In 10 minutes I was up and running again - Ever see a BBC push rod plant itself into the roof of your garage - I've seen them go throw the Fibre Hood of a Vette - LOL

IF your running any short of spring pressure, I recommend Roller Rockers and not the CHEAP ones. I suppose the OEM Rockers are OK with a Hydraulic Cam but if your over .5 Lift with a short Duration better go Roller. You can't run more then 122lbs on the seat with a FT Cam or you asking for it. I will always run a Roller Rocker with a SFT or SR Cam.

Lazy Springs will also Break Valve Train Parts and Guides, Pound Valve Seats and possibly wreck the Cam.

One time I didn't care if my head was under the hood while the lights changed - To Day I'm MUCH MUCH older and would sooner be on my way ;o)

Well I picked up a set of Comp Magnum roller rockers today. The engine was built in 1989 so the specs were long lost on what was in the motor. Previous owner was sure it was a hydraulic comp cam and spring set upgrade used when the heads were rebuilt. From the characteristics of how the engine runs and the descriptions on the comp site, I am fairly certain it is one of the milder .510 lift cams since the car is running the stock torque converter and has a slightly rough idle. I think I am going to change out to new pushrods as well just to make sure everything is fine.

the problem is with the sloted rocker arm balls. THEY ARE JUNK. Caused me a lot of problems. The slots acutally pull oil away from the rocker arm seat/fulcrum area.
Larry 2206 AA/SA