Topic: Need Advice
in Forum: C3 Engines
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Former Member
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Bladenboro, NC - USA
Joined: 1/22/2006
Posts: 1058
Vette(s): 1972 conv., sunfire yellow, blk interior, blk vinyl and convertible top. Off frame restoration with American Speed 383 stroker engine producing 500hp plus a 200hp NOS system. MSD ignition. Hooker super competition headers with chambered exhaust.
I've had an irritating small oil leak from the back of my intake for the past 6 months. A friend came over today to help me replace the intake gasket. I drove the car yesterday and noticed it didn't have the power it usually does, so I decided to check the plugs while we had the intake and valve covers off. I have 2 fouled plugs which just so happens to be #4 and #7 cylinders. That's the same ones that broke the rocker arm studs last summer.
While I have the intake off, should I go ahead and pull the heads and have them checked for a warped valve or whatever is causing those 2 cylinders to foul the plugs? Will I be able to get the heads off without taking the headers completely off? Is it likely that I damaged a piston when the rocker arms broke or do you think the problem is in the heads?
While I have the intake off, should I go ahead and pull the heads and have them checked for a warped valve or whatever is causing those 2 cylinders to foul the plugs? Will I be able to get the heads off without taking the headers completely off? Is it likely that I damaged a piston when the rocker arms broke or do you think the problem is in the heads?

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Duncanville, TX - USA
Joined: 11/8/2003
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
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Was it fouling the plugs before you pulled/installed the intake? If not, chances are the intake gasket slide down a bit while putting the intake back on. This would allow oil to be sucked up into the intake ports.
(Never mind...I just re-read the post.
)
I would suggest a compression test first. Even with the intake off, you can still do a comp. test. Doubtful that you hurt the pistons. You may have damaged the valves, tho. They may have enough of a "bend" in the stems to be sticking, or wearing the guides enough to suck some oil down them. You might check to see if the valves on those two cylinders still have the seal on them. It's possible that when the rockers went bonkers, they mashed the seals into oblivion...
(Never mind...I just re-read the post.


I would suggest a compression test first. Even with the intake off, you can still do a comp. test. Doubtful that you hurt the pistons. You may have damaged the valves, tho. They may have enough of a "bend" in the stems to be sticking, or wearing the guides enough to suck some oil down them. You might check to see if the valves on those two cylinders still have the seal on them. It's possible that when the rockers went bonkers, they mashed the seals into oblivion...

Joel Adams
C3VR Lifetime Member #56
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Former Member
Send PM
Bladenboro, NC - USA
Joined: 1/22/2006
Posts: 1058
Vette(s): 1972 conv., sunfire yellow, blk interior, blk vinyl and convertible top. Off frame restoration with American Speed 383 stroker engine producing 500hp plus a 200hp NOS system. MSD ignition. Hooker super competition headers with chambered exhaust.
We took the heads off today and i'm taking them to Warren Racing Engines tomorrow. I really hope it's in the heads because I certainly don't want to pull the engine out.
Joel, I suggested we do a compression test but my buddy said that still wouldn't tell us if the problems was in the heads or the piston. This high hp stuff is fun but it dang sure ain't cheap.
Joel, I suggested we do a compression test but my buddy said that still wouldn't tell us if the problems was in the heads or the piston. This high hp stuff is fun but it dang sure ain't cheap.

i HAVE TO AGREE WITH YOU THERE JIM. SEEMS LIKE I`M ALWAYS REACHIN` IN THE POCKET, AND i ONLY HAVE ABOUT 1000 MILES ON HER. GOOD LUCK I HOPE IT SOMETHING SIMPLE. I REMEMBER I BROKE A ROCKER STUD TOO SHORTLY AFTER THE ENGINE WAS INSTALLED.
Former Member
Send PM
Bladenboro, NC - USA
Joined: 1/22/2006
Posts: 1058
Vette(s): 1972 conv., sunfire yellow, blk interior, blk vinyl and convertible top. Off frame restoration with American Speed 383 stroker engine producing 500hp plus a 200hp NOS system. MSD ignition. Hooker super competition headers with chambered exhaust.
[QUOTE=VETTERBOB]i HAVE TO AGREE WITH YOU THERE JIM. SEEMS LIKE I`M ALWAYS REACHIN` IN THE POCKET, AND i ONLY HAVE ABOUT 1000 MILES ON HER. GOOD LUCK I HOPE IT SOMETHING SIMPLE. I REMEMBER I BROKE A ROCKER STUD TOO SHORTLY AFTER THE ENGINE WAS INSTALLED.[/QUOTE]
Did you have the 3/8 rocker studs or the 7/16? I had the 3/8 with 1.5 Harland Sharp roller rockers but changed to 7/16 with the 1.6 Harland Sharp rockers after it broke the 2nd stud. I thought I had the problem solved but I guess this damage was done when the 2 original studs broke. I have almost 2400 miles on the engine and if anything else happens to it, my original engine is going back in the car.
Did you have the 3/8 rocker studs or the 7/16? I had the 3/8 with 1.5 Harland Sharp roller rockers but changed to 7/16 with the 1.6 Harland Sharp rockers after it broke the 2nd stud. I thought I had the problem solved but I guess this damage was done when the 2 original studs broke. I have almost 2400 miles on the engine and if anything else happens to it, my original engine is going back in the car.
Former Member
Send PM
Bladenboro, NC - USA
Joined: 1/22/2006
Posts: 1058
Vette(s): 1972 conv., sunfire yellow, blk interior, blk vinyl and convertible top. Off frame restoration with American Speed 383 stroker engine producing 500hp plus a 200hp NOS system. MSD ignition. Hooker super competition headers with chambered exhaust.
Got the call from the engine shop today. There is nothing wrong in the heads. We checked all the pistons real close and there's no indication that anything has hit a piston.
I think Joel might have diagnosed the problem when he said it's possible the intake gasket was not completely lined up and allowed oil to be sucked up into the intake ports.
Any suggestions as what to do next?
I think Joel might have diagnosed the problem when he said it's possible the intake gasket was not completely lined up and allowed oil to be sucked up into the intake ports.
Any suggestions as what to do next?

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Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20214
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
Fix it!!!

Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Former Member
Send PM
Bladenboro, NC - USA
Joined: 1/22/2006
Posts: 1058
Vette(s): 1972 conv., sunfire yellow, blk interior, blk vinyl and convertible top. Off frame restoration with American Speed 383 stroker engine producing 500hp plus a 200hp NOS system. MSD ignition. Hooker super competition headers with chambered exhaust.
[QUOTE=Adams' Apple]Fix it!!!
[/QUOTE]
I need to know what to fix.


Former Member
Send PM
Bladenboro, NC - USA
Joined: 1/22/2006
Posts: 1058
Vette(s): 1972 conv., sunfire yellow, blk interior, blk vinyl and convertible top. Off frame restoration with American Speed 383 stroker engine producing 500hp plus a 200hp NOS system. MSD ignition. Hooker super competition headers with chambered exhaust.
I went to pick my heads up today and decided to carry my old head and intake gaskets so the "experts" could inspect them. They seem to think that was my problem, atleast on one of the cylinders. I also had the valve stem seals replaced since the heads were already apart. Everything else looked fine.
I was a little surprised at the cost of labor for checking the heads and replacing the stem seals. ($200.44) Head gaskets, header gaskets, intake gasket and valve cover gaskets another $101.
I was a little surprised at the cost of labor for checking the heads and replacing the stem seals. ($200.44) Head gaskets, header gaskets, intake gasket and valve cover gaskets another $101.
in Forum: C3 Engines
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