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Topic Review (Newest First)
03-06-2013 02:33 PM
91chevyss Havent checked block yet. I did take my head to the machine shop to get looked at but wont know anything till tomorrow. He said if it needed shaving then he could do both for $100. If the heads are required to be shaved should I get that done or try to buy some used vortec heads and an intake to match?
03-06-2013 09:43 AM
morcey2 Now that's talent! I've seen some weird stuff, but to me that screams that someone forgot to torque the head gasket all the way or something like that. Did it damage the block deck surface?

Matt
03-06-2013 09:25 AM
oldbogie
Quote:
Originally Posted by 91chevyss View Post
Putting oil in the cylinders didnt help and I loosened the rockers a little and that didnt help either so I pulled the head and didnt see any cracks in the head or piston or valves and I pulled one valve out to see if it was seating properely, it was ok but not great. The only thing I found was a break in the head gasket between 2-4 and 6-8 but not 4-6 so Im guessing this is my problem. what do yall think?
This is one for the record books. I wonder if Guinness has a catagory for strangely blown head gaskets.

I'm thinking that if there was enough coolant in the center cylinders to blow out the gasket material in the outboard cylinders that digging into the bottom end looking for cracks in the pin bosses, bending of the rods, crushing of the rod bearings, etc. is in order.

Off the top of my head with your first post my guess would have been a problem with the compression gauge, like the thing leaking down through the Schrader valve from a small piece of dirt holding it off its seat. This is way different.

Bogie
03-06-2013 07:34 AM
91chevyss there was a little debris in the water jackets of the head from running water but I have an electric water pump that had problems with my connection and had a freeze plug leak. Since then I have replaced the freeze plugs and fixed my water pump issue.
03-05-2013 11:26 PM
PatM You might want to look for a cause of that overheating. Perhaps some sort of debris in yhe passenger side head? I don't know enough about the cooling system to "guess" what might be happening. But if you have it torn down, and it overheats again, you might blow out another gasket. You might want to investigate around a bit while it's opened up.

Pat
03-05-2013 11:14 PM
91chevyss yes it has more than once lol
03-05-2013 10:52 PM
PatM I once severly overheated an engine (a 350) and both head gaskets blew in two places as your one gasket has. Was the engine running hot?

Pat
03-05-2013 07:30 PM
91chevyss whats a good gasket to use?
03-05-2013 07:28 PM
91chevyss Im hoping improper torque but head looked flat took a straight edge to it but havent checked block.
03-05-2013 07:04 PM
crownver That's definitely your problem. Now you have to find out why it blew like that. Incorrectly torqued head bolts, warped head, block deck not flat?
03-05-2013 07:00 PM
T-bucket23 No question that is your issue. Improper torque is my guess
03-05-2013 06:52 PM
91chevyss Putting oil in the cylinders didnt help and I loosened the rockers a little and that didnt help either so I pulled the head and didnt see any cracks in the head or piston or valves and I pulled one valve out to see if it was seating properely, it was ok but not great. The only thing I found was a break in the head gasket between 2-4 and 6-8 but not 4-6 so Im guessing this is my problem. what do yall think?
03-05-2013 05:43 PM
GMC boogie Good point P-body! Possible valves too tight on that side.
03-05-2013 05:31 PM
Mr. P-Body If the gasket were "blown" that badly in all four cylinders, surely there would be a "hissing" noise very obvious.

I suspect the rockers are too tight on that side. You can put an air fitting on the end of your compression tester hose and plug air into the cylinder. Listen to where it comes out (carb or throttle body, exhaust or up through the pushrod area). If it's the cabr/TB, loosen the intake rocker and see if it lessens. Same with exhaust. If you hear it plainly but loosening doesn't "help", pull the head....

WIth numbers that "low", I would believe if rings, the wrong size rings were installed. That WILL "come up" significantly when you squirt oil in it (use heavier engine oil, "liberally").

Numbers on the other side are pretty normal for a "hot" cam. The lift number is nice to know, but the duration tells us a lot more about the cam. The "@.050" numbers are the best to use for general comparison. LSA (Lobe Separation Angle) is also important.

Jim
03-05-2013 03:19 PM
T-bucket23 Even side could have been torqued wrong. I would also check to see if the exhaust is somehow plugged on that side. It would be unusual for the head gasket to blow on all 4 cylinders unless it wasnt torqued properly. It would also be unusual for the rings to wear just on that side.
I have also seen loose spark plugs cause valves to burn. Were they all tight. I was thinking maybe someone changed them and never tightened that side.
Also more history would be helpful. Was this a new build, were you driving it and it started running bad. Poor valve adjustment could also be causing your issue
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