About a week ago I had my 75 vette out after a hard run down the road pulled into my driveway. Had coolant coming out around the radiator cap very fast going everyone. Shut the car off and let it cool and later refilled it. Took it for a test drive and quickly had the same problem. Replaced water pump and thermostat tried running the car with cap off to burp the air from the systerm. Within minutes of refilling the cooling system and running the car with the cap off coolant was coming out in massive quantities without even being all the way up to temperature. I am talking a gallon plus. The new coolant also had a very strange smell. Though out research and talking to some people everyone stated exhaust gas was getting into the cooling system and causing the excess heat and pressure. I have also always had issues with coolant leaking between the head and the block from the head gasket near the 4 and 2 cylinder.

Today I began to pull the motor apart hoping to see a very obvious sign of the exhaust leak. I didn't see any major damage or signs on the current head gasket except for some crude buildup along the bottom where the coolant was leaking. I looked over the head and do not see any signs of cracks or damages. Is there any for sure way of knowing where the problem is coming from? Attached are a few pictures from today. Also the passenger side spark plugs appear to have some stuff on them that the driver side did not. Did not get a chance to pull driver side head yet.

 

First off I would have the heads magna-fluxed. If no cracks, new head gaskets.

 

From the looks of your pistons and spark plugs I can easily tell your piston rings are shot and its time for a complete overhaul.

 

What about the look of the Pistons makes you think the rings are shot? Sorry I am a novice learning on the fly right now. What should everything look like stripped down to this point?

 

You appear to have one piston that doesn't match the others.

 

What does the oil look like? Is it murky at all? That "sludge" looks like there is coolant in the oil. And all that fouling in the cylinders and plugs. If you're getting oil in the coolant, you're probably also getting coolant in the oil. You're going to be very lucky if this is just a blown head gasket at this point.

 

Interesting.....the"washed" part of the piston is what gets my attention. This is caused by coolant getting into the combustion chamber and essentially steam cleaning the parts. If the water gets in there, it can also flow the other way as well, in the form of combustion bubbles in the coolant. It looks to me like its a problem in a few cylinders. The piston in #4 is definitly different, so maybe when it was reassembled they didn't torque the heads properly and this caused the gasket leak.
clean it up best you can, install a good head gasket, run the engine and then let it cool, and then retorque the heads.....good luck

 

Well, since you have one mis-matched piston, I think it would be wise to do the complete tear down and rebuild. It's obvious some jerk has done a hatchet job on your motor during a previous teardown.