carbon di oxide in radiator

[mike gaines]

My Hawk from hell continues to punish me !
I have CO2 coming through my radiator , I have pressure tested the heads , no problem , head gaskets checked , no problem. Is it possible for a crack in the block to allow CO2 to get into the water ? If not , what else can I check

[DEEPNHOCK]

If you are talking about bubbles in the coolant, and all your checks are good, then it is probably from a cracked cylinder (or maybe still a head gasket).
When you say you 'pressure checked' your heads, and head gaskets, are you saying you ran a compression test?
If you ran a compression test, did you run a 'leakdown test'?
There is a difference between the two test methods.
But.....
Pressure test your cooling system with a leak down coolant pressure tester.
If the cooling system will not hold a pressure.
Look for leaks externally, but suspect a cylinder crack (and keep thinking head gasket for the karma value).
Either way, you will be pulling the heads to look further, so look real close at the head surface, the block surface, and the head gasket when you first take it apart.
Hope the info helps.
Jeff[8D]

quote:Originally posted by mike gaines

My Hawk from hell continues to punish me !
I have CO2 coming through my radiator , I have pressure tested the heads , no problem , head gaskets checked , no problem. Is it possible for a crack in the block to allow CO2 to get into the water ? If not , what else can I check

[JDP]

If you mean you are detecting combustion gases in the radiator with a sniffer, it's likely a head gasket.

JDP/Maryland
64 R2 GT (Sid)
spent to date $62,839.60
63 Daytona HT/4 speed
63 Lark 2 door

[curt]

I had a leaking head gasket years ago . I would be on a good highway run and stop. When the engine was stopped immediately after the highway run the radiator would vent fluid. Now I should define the stop and shut down: pull off the highway and stop immediately in a parking lot. That was when the fluid STARTED to flow. As I recall a compression test was compatible with a blow gasket, two adjacent cylinders were off specs.

[64studeavanti]

Same problem on my 64 Avanti R1. It would overheat - coolant would pour out of the vent. The compression test looked ok, however, I did not do a leak down. There were bubbles in the coolant. Pulled the heads, had them shaved and put everything back together with the thick gaskets(trying to keep the compression down a little). No problem since. It has never run above 190. I did flush the block as everyone recommends - boy did the crud come out.

[mike gaines]

Thanks for all the good advice. Yes , the carbon di oxide was detected using a sniffer. I have pulled the heads off again and I notice that the gasket between the two inner cylinders on both heads has a darkish stain on the gasket between the cylinders and the nearest water channel . The gaskets have not blown. I recently pressure tested the heads and checked that they were not warped. The head bolts torque down properly and its a new gasket.Does this mean that the block is warped , I cant see any distortion using a straight edge and a backround light , accross the block.