Originally Posted by orange rush (Post 1586912090)

You could drain the oil and get a magnet extension to feed through the oil drain and see if it catches anything. Long shot but worth trying. I am on the hunt myself for a valve spring lock. It popped off and I can find it either. :willy:

Originally Posted by Arclight (Post 1586912232)

When you did the compression check-that cylinder was "next to zero"? :eek:, obviously both valves should be closed to get a reading on the compression gauge- why don't you have compression? Is it possible the valve got bent prior to the rocker arm failure?You should try a leak down test next-that would immediately show if either valve is bent. The broken stud-or what remains of it is a big concern-but the compression check should be normal if all that has failed is the rocker arm.Not to mention just fixing the broken rocker stud is not addressing why it broke in the first place. Looks like you have a lot of work to do-that broken stud and nut HAS to be found, if it means the motor comes apart so be it. It'll find its way out of the engine-one way or the other....:ack:

Originally Posted by petsur (Post 1586915125)

Makes sense what you're saying. The guy that did the cam also did Comp's trunnion upgrade but did not use the new rocker bolts that come with the kit. He used the factory rocker bolts.

Originally Posted by QKSLVRZ (Post 1586916354)

That looks like an intake(?), if it was, since the intake valve didn't open, I would expect to see very low compression during a compression test.

Originally Posted by QKSLVRZ (Post 1586916354)

That looks like an intake(?), if it was, since the intake valve didn't open, I would expect to see very low compression during a compression test.

Originally Posted by Arclight (Post 1586916849)

Forget the compression test. Use a leak down tester. Basically the engine is rotated until both valves are closed. The spark plug is replaced by an air hose,using a regulated air supply- put 100psi of air into the cylinder-no leakage at all is not going to happen but 90%+ should not escape. If the intake is bent or has a damaged seat the air will escape through the intake tract and can be heard coming from the manifold,conversely if the exhaust valve has damage the air will leak through the exhaust manifold. Some leakage is to be expected in a cold engine with some escaping by the rings. A compression test is a good fast way to compare cylinders but with a leak down-you KNOW what psi is going in- as well as coming out:thumbs: IMO, you MUST find that broken stud- not to mention the fact that if it shattered,there is enough small debris floating around in the drive home-that might have been captured by the oil filter. Either way- that motor has to come apart- at least the top end. You also have to wonder if the lifter was damaged in anyway. Upgraded rocker arms are a must if you are doing track days-Jesel or T&D might be overkill-but they won't break. Not to mention establishing a maintenance schedule to check the seat pressure on your valve springs. Better to replace weak springs than dropping a valve.:eek: Unfortunately, it will probably easier to get the broken stud out with the head removed on a work bench than over an open motor. Hopefully its not your DD.

Originally Posted by petsur (Post 1586915125)

Makes sense what you're saying. The guy that did the cam also did Comp's trunnion upgrade but did not use the new rocker bolts that come with the kit. He used the factory rocker bolts.

Originally Posted by taken19 (Post 1586917768)

Epic fail! The new bolts are a must because they are about 1/4" shorter than stock. The stock bolts will bottom out in the blind hole and never clamp the rocker down... Ask me how I know. I had a reputable forum vendor make the same mistake on a new motor in my old C6 and I broke a rocker bolt on the track - I thought I lost another motor. I tried to easy out the bolt myself with no luck. I ended up taking it to a machine shop to get it extracted and help-coiled. Pretty cheap fix, but I would be all over the shop that made this mistake! Don't worry about the motor. As soon as that bolt broke, the valve stopped moving and shut that cylinder down. No other harm was done. http://forums.corvetteforum.com/auto...the-track.html Edit: if you can't find the head of the bolt, you may have an issue. You need to find it. Check all the oil drain holes?

Originally Posted by petsur (Post 1586917351)

Well, I drilled on that broken easy out for 3 hours and only got a good dimple in it. I gave up and a local speed shop is going to pick up the car and make the required repairs.

Where I didn't break any springs, do you think I still could have had a valve hit the piston?

Originally Posted by petsur (Post 1586918462)

Yeah, I just crawled under the car again and can't find the fukr. There's no debris like it got chewed up and too big to fit in the oil drain. The piece that broke off was about 1" long.

I put a head of a bolt up to the oil holes and it's waaay bigger. Looked in the valve springs and don't see it.

If you look at the picture, the broken rocker was up high against the valve cover. I'm hoping it fell out when I pulled the cover off and wrestled it under the vacuum lines.

Originally Posted by taken19 (Post 1586919117)

You have to find the bolt piece. Until you do, be very cautious on motor options. Best of luck man.

Originally Posted by taken19 (Post 1586920263)

Take a magnet and swing around the engine bay. Maybe you get lucky and find the bolt.