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Discussion Starter #1
What do I expect? I found a dead spark plug on # 7 cylinder, approximately 3 races ago. Changed all plugs, car ran fine for 2 times out. Recently the car sat up for about 2 weeks, tried to crank, and wont turn over, battery good, moved the flexplate with turning tool approx. 2 inches, car cranks good with plenty power. Car started but blew moisture out of the driver side header, sounds like running with a miss, kinda like another dead cylinder, Didn't yet pull plugs, but will pressure up the water jacket thru the radiator cap tomorrow when I get off work. I did check and low on water. What do I look for when pressuring the cylinder, or what are my next steps?

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If you suspect a head gasket, I would probably do a cylinder leak down test. My kit has gauges which shows how much it's leaking. But basically, you want to make sure the cylinder your testing is at TDC. Make sure valves are all the way closed. Pump some air in the cylinder. My gauge is set for 90psi. Listen for air at Carburetor (make sure you open the throttle), check for bubbles at the radiator (make sure it's topped off), at the exhaust and at the crankcase (pcv, breather, etc...). Most likely it's a head gasket. How do the plugs look? whitesh residue? Is it smoking?
 

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My guess is you have a slow leaking head gasket. DON'T run it again! Take the plugs back out and you will most likely know immediately which cylinder it is (as the water will run out the plug hole.) Low water level in radiator is a big sign of this. The miss sounds like another good sign. When you moved the flexplate that most likely pushed out some water and enabled you to fire the engine. But the longer it sits (and/or runs too) the more water leaks into the cylinder and if you try to start it again it will eventually hydraulic the engine. (This is where bad things happen like bent rods, bent valves etc.) All it takes is a small burnt spot in the head gasket to cause this. Be happy you caught it early. Not a big deal to fix, just make sure to inspect both the head and block surface for blemishes that may have been caused by the cylinder seal being compromised. You can do a leakdown but I'm pretty sure you're going to remove the head no matter what in this case. Let us know what happens and good luck! If you want more help, happy to answer any questions too!

P.S. Also possible you have an intake leak so I would check the gaskets carefully when you remove the intake as well.
 

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Discussion Starter #4
Why do I get all the confusing problems? well I pumped up the cooling system today, thru the radiator cap, up to 17#, after 30 mins, it dropped to 14#. I pulled all the plugs, all look good, no white or rust. Turned engine over with all the plugs out, no water or moisture. I cranked it, to get the oil churning, didn't run long enough to get hot, just warm. The oil is clear, no water. ?????
 

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When you said earlier that you found a "dead spark plug" what exactly did it look like? Black? pinched shut? wet? smelled like fuel? description..?
 

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Discussion Starter #8
Actually I made 3 passes, at that time when I couldn't figure out how i loss 1 sec. of et. After checking headers, found # 7 cold, plug was black, but no damage. Changed all plugs, ran fine since.
 

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Hmmm, well if it were me I would check all the plug wires to make sure they look good, make sure the alt/charging sys is working and do a leakdown as well. That should rule anything out. It may just be a weird combinations of events that happened at the same time.
 

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Water Problem

I had a 327 a long time ago that lost a little water in the radiator and missed a little at first engine start up. I filled the radiator full and pumped the pressure up with a pressure tester and went to bed. :sleep: In the morning pulled all 8 plugs and pumped pressure back on the radiator with the pressure tester. Then I spun the engine over and watched a little water spurt out of #2 cylinder. What I had was a cracked head and as soon as the engine got warmed up a little I guess the crack would close up. I never got any water with a quick test, but letting it sit overnight and cool off revealed the leak. I hope yours is just a head gasket. Good Luck
 
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