combustion in the coolant?

[tregrad]

I have gone through 2, TWO! cold case radiators in my Blazer. I have to give props to coldcase though, they sent one to replace the first one I purchase free of charge last october and that one started leaking today. I walked out to the driveway and it was leaking, hadnt even started it yet.
needless to say i am a bit pissed, called coldcase and they said take a pic of the serial number and the leak and they will send out another!! many props to them and their lifetime warranty.
Now, the dude on the other end of the line told me that there could be "combustion" in the coolant? and that could be causing the pressure that is blowing the radiators apart. I personally, in all my years of being a home garage gearhead have never heard of that until today. He said that there wouldnt be the usual signs of water on the plugs or coming out the tailpipe but could be causing the pressure, said he had a 454 that was doing this. Said he changed the head gaskets and the problem went away.
Can a head gasket be bad as to let combustion into the radiator and not into the cylinder ?

[MySons68C20]

The radiator cap should pop before the radiator fails.
If you have a bad head gasket it can pressurize the radiator, leak externally or both.
Normally you should see a loss of coolant either way.

[Dead Parrot]

2nd on the cap releasing pressure before the radiator splits. Get a new cap even if current one is fairly new. QC could have failed.

Could be possible that you have a small enough head gasket leak or crack to let combustion air into the water spaces but not water back into the cylinder. Once the fire lights, pressures get really high, hundreds if not into the low thousands of PSI. The max for the water should be the cap rating. Test run it with full water but cap off. If there is leakage, you should see bubbles in the radiator.

Are the radiators leaking from the same spot? Maybe some assembly person needs a bit of additional training.

Nice to hear that a company stands behind their products.

[AussieinNC]

Sounds lie the tech was referring to combustion gasses leaking into the coolant.

All agree this should force the radiator cap to reach max pressure and vent out excess.

If the radiator is swelling before the cap releases, there must be something wrong with the radiator design or build.

Are you mounting the radiator solid to the chassis? If so, perhaps the frame is flexing placing extra stress on the radiator.

Here is a simple radiator test kit to check for combustion gas in the coolant.

https://www.amazon.com/Block-Tester-...YaAuw0EALw_wcB

[jerry moss]

Originally Posted by AussieinNC

Sounds lie the tech was referring to combustion gasses leaking into the coolant.

All agree this should force the radiator cap to reach max pressure and vent out excess.

If the radiator is swelling before the cap releases, there must be something wrong with the radiator design or build.

Are you mounting the radiator solid to the chassis? If so, perhaps the frame is flexing placing extra stress on the radiator.

Here is a simple radiator test kit to check for combustion gas in the coolant.

https://www.amazon.com/Block-Tester-...YaAuw0EALw_wcB

we use that same block test kit at work and it's simple and accurate.

[tregrad]

Originally Posted by MySons68C20

The radiator cap should pop before the radiator fails.
If you have a bad head gasket it can pressurize the radiator, leak externally or both.
Normally you should see a loss of coolant either way.

I agree totally but, don't you think that even if the cap was bad that it would be forced open before blowing out the radiator?