I bought a new heater core. So how do i properly pressure check a new heater core for leaks before installing it? i want to make sure it doesn't leak before waisting all that time installing it. any ideas? or proper way to test it for defects?

 

If I were doing it I would take a piece of heater hose and connect it to the 2 pipes on the heater core. I would put a T in the hose with some fittings so I could use my air hose to pressurize it. Set the pressure regulator to about 15 psi and put the heater core under water to see if it leaks.
Kind of a pain but much less painfulk than installing it, having a leak and getting to do it all over again.
Smart move on your part.

 

that sound like a good idea. where can i get a T fitting that would fit the hoses? i do have an air compresser but im not sure how to connect it to the rubber hoses to pressurize the heater core. have you done this before?

 

Yes I have rigged up similar ways to air test things for leaks such as this. I havd a big coffee can full of assorted pipe fittings etc. that I keep for things like this.

Go to the hardware store or auto store and you can buy a metal tire valve that has 1/8" pipe thread on the other end. The air chuck you fill your tires with will fit on one end and the other end will be 1/8" male pipe thread. The rest of the parts can come from the hardware store. Metal is available but plastic should be cheaper. You need a tee and 2-5/8" hose barb fittings for the hose, and reducing fittings for the other branch of the tee that will take you down to 1/8" female pipe thread so you can screw the tire valve into it. Also a couple of hose clamps.
Just be sure you don't over pressurize it and cause a leak in the heater core. The system is designed to run about 15 psi. A new heater core should hold more than that but I do not knowhow much. My guess is you could safely fo to 18-20 psi but I would not go over that and there is no reason to go higher.

 

I just thought of a simpler and cheaper way if you have access to a 1/8" pipe tap. Get a piece of thick wall plastic pipe at the hardware store that will slip into the heater hose. Drill & tap the pipe to 1/8" pipe thread. Then use the fitting I described above.