CamaroFreak87

First of all, car hasn't been running right since I rebuilt the engine. I ended up binding the original rockers with my new cam, so I replaced the rockers with comp cams magnum 1.52 roller-tipped rockers. Later, I bought some chromemoly pushrods to go with it. I have the magnum rockers on there already, and was going to install the pushrods today. Open up my valve cover and one of my rockers fell to the ground! Hmm...something tells me this is a bad sign...The number 2 cylinder sheered the exhaust stud in two. Anyone know what would cause this? I've been running the engine very easily since I put the magnum rockers on, because I didn't want the rockers to develop a wear pattern with the pushrods because I knew I was getting new ones later. Would a stud girdle help?

I figure it's time for some new heads. I'm stuck with the 3/8" stud and self aligning, because that's the type of rockers I bought and they cost $200. When I do get new heads, I'd really prefer not to break off any more studs...

Ryan

ede

i'd think you need to check your valve train geometry for the reason the stud broke. if you have pull out studs you can buy a repair type stud to keep you from having to pull the head. with the lifte you're running screww in studs would be a smart move

jimmy_mac

From my limited experience, which has seen more broken studs and bent pushrods than I should have, binding at some point is more than likely the culprit for a broken stud. Are you sure your retainer is not smacking your valve guide?

Also I had a damper break (actually several broke) inside the spring and wedge in between the coils. I heard it happen. It went tick, tick, tick, snap. Then I was on 7 cylinders. Pushrod didn't bend at all.

CamaroFreak87

Ede, how would I pull the broken stud out? There aren't any threads left. Where can I buy the repair type stud? I'm sure I'll need a special tool to remove/install this, where can I get those? Thanks.

The lift at the valve shouldn't be more than .515", so I didn't think screw-in studs were a necessity yet.

Ryan

Motor City Mike

It also sounds to me that you have some sort of mechanical interference which caused your stud to break. In addition to the previously mentioned items, check the rocker arm (from the failed stud) for witness marks of it hitting/rubbing somewhere (valve retainer area, stud slot, etc.). You may need different length pushrods for your combination to restore your valvetrain geometry, to prevent this from happening again.

Check with a local automotive machine shop for tips on removing the broken stud and getting/installing a replacement. Hopefully it isn't broken off flush with the head. I do know that the studs go into the water jacket, so be sure to drain your cooling system before attempting to remove it. I replaced a pressed in stud some years ago with a screw in stud, because the threaded end was messed up. It was a shoulderless stud so the cylinder head didn't need to be spot faced in the area around the stud. If you go this route, when tapping the hole, it is very important that it is kept perfectly straight, and inline with the other studs.