C3 expansion valve
Thread Starter
Drifting
Joined: Aug 1999
Posts: 1,451
Likes: 84
From: Round Rock TX
C3 expansion valve
I have the original expansion valve and would like to use it again. Is there a way to test it to verify that operating correctly off the car? I know they can be "rebuilt" but would like to see what I can do myself.
Melting Slicks
Joined: Feb 2006
Posts: 3,105
Likes: 96
From: Sunrise FL
Well no body answered so here goes...see if it holds a vacuum. Not sure how to check the temp sensing/press regulation.
Give it a good cleaning/inspection and try it. If you are in this far I would convert to R134, cheaper in long run.
Give it a good cleaning/inspection and try it. If you are in this far I would convert to R134, cheaper in long run.
Burning Brakes
Joined: Mar 2014
Posts: 904
Likes: 46
From: Crestline CA
Valve is a pretty simple device, its function is to close off the flow of refrigerant when the evaporator get too cold to prevent it from freezing over. When the sensing bulb sees a too low temperature it shuts the valve.
Couple of quick tests. See if you can blow through it with the sensing bulb at room temp, you should be able to. Second is to cool the sensing bulb, it should mostly, if not completely close the valve. I've used a can of refrigerant in the past to cool the bulb but thats a no-no nowadays, Never tried but a freezer may do the trick.
Couple of quick tests. See if you can blow through it with the sensing bulb at room temp, you should be able to. Second is to cool the sensing bulb, it should mostly, if not completely close the valve. I've used a can of refrigerant in the past to cool the bulb but thats a no-no nowadays, Never tried but a freezer may do the trick.
