Re: Radiator Coolant Foaming

Posted by Owen_Dyneto On 2015/3/19 9:15:06

Heaters were not standard equipment so it's unlikely that whatever coolant they might hold would have been included in the capacity of the cooling system. And generally a typical hot water heater would not hold as much as a gallon. But the "foaming" suggests other possible issues such as a blown head gasket or a cracked cylinder block or cylinder heat, even possibly a bad water pump seal allowing air to be sucked in. I suggest you start with a compression test of the cylinders.

Also, any evidence that the original radiator was replaced with one of a smaller capacity?

You made no mention of whether the car is overheating but that's my assumption. If your compression test shows no problems, I'd start by removing the water jacket plate and doing a thorough scraping and cleaning of the water jackets and the manifold within the plate itself. That done, I'd then give the radiator a vigorous back flush followed by a flow rate test. Then I'd subject the entire cooling system to the standard oxalic acid (followed by a neutralizer) chemical cleaning. While you're at it, remove and check the water pump for such things as a corroded or slipping impeller and leaking seal (just repack with graphite cord if needed).