How to pressure test the cooling system?

Just to put a conclusion to my problem. I never figured out how to do the pressure test but surmised the problem was with the hose clamps and the hoses on top. When removing them it was apparent that two of them had been cut short and were barely covering material. I replaced them with longer hoses. Refilled the radiator with water and ran the engine.

George Van Nostrand has been having computer trouble and asked to post the attached picture.  It shows a novel design of fitting a pressure cap low down on the vent tube. He fitted a 2 lbs pressure cap but it blew the original tanks.
As mentioned earlier my radiator has a pair of tanks made by George Ehresman with the cap also supplied by George Ehresman. I checked the cap pressure which is stamped on the top. It is 4 lbs.





 

Here's what I use. It pressure tests as well as vacuum system to fill. Cost about $90.00 on Ebay. Has about every adapter known. Don't forget to plug overflow tube.

Pat Leahy

Here is a method of pressurizing a Cord radiator .

Terry, I do have an 18V pump and that was my plan. But looking at the drain line and where it ends I have a new plan. I'm 90% sure the leak is in the upper radiator hoses, so I'm ordering some new ones and will probably run modern clamps with the originals in a box in the trunk. 

AJ my radiator tanks were made by George Ehresman and supplied with a modern type cap. I think from memory the pressure is 4 psi. I will check it tomorrow.
Pressure testing the oil pump pressure relief valve I used an 18 volt Makita tyre pump. It has a digital read out in 0.5 psi steps. You could easily use one of these to check the cooling system.

Thanks guys. Will check out the overflow as a possible way to put a 1 or 2 psi in to the system. I know not to use compressed air.

A.J.

All 810 or 812 cooling systems are zero pressure. To the drivers side of the top radiator tank is a piacular raised bump. Thats the tank overflow and it runs down the drivers side of the radiator to the ground. I was advised to not fill the radiator to the top neck. That way when coolant expands it wont run out this tube. Just run the top tank half full and it will be fine. I got this information from Jim O Brien as I recall.


Gary Parsons

You may be able to pressurize the system through the overflow tube.  If you don’t pressurize it there you will have to block it off in order to hold pressure.  Also my understanding is that these old cooling systems that were not designed to be pressurized should only be pressurized to a few psi at the most.  The original cap may suffice to hold this low level of pressure well enough for you to find the leak.

Could anybody point me in the direction of an adaptor or an aftermarket cap I could drill that would allow me to pressure test the radiator on our 812?   I have a coolant leak that sprayed anti-freeze everywhere.   I believe it is the upper hoses but would like to confirm before I replace them.

I see relatively cheap test kits that come with lots of adaptors but not sure which if any will work.