By: James, San Jose, CA. My compressor is a Montgomery Wards brand 220v/1.5 hp 20 gallon model, with a Franklin Electric motor, a two-cylinder compressor, and a Kargard Industries tank. The date code on both the tank and the motor are 1972.
Montgomery Ward Air Compressor

Question
It seems my compressor has the same symptoms as a previous poster – it will not pressurize the tank above ~40 PSI. When the compressor is first turned on with the tank unpressurized, I can feel the cylinders sucking in air as they should; but as the pressure builds, more and more air is pushed right back out the intake valve. As with the previous poster, I disassembled the heads on my compressor to check the valves. They’re just flat reed valves, and appeared to be in fine condition, just a little dirty. I cleaned the valves, head, and ports copiously, replaced the gaskets with new ones, and reassembled. But this did not solve the problem. Neither does changing or even removing the air filter.
Bill, you mentioned something about a “check valve going into the tank” in regards to the previous poster’s problem. While his problem turned out to be a head gasket issue, it doesn’t appear that mine is, so I would like to know more about this check valve. What is its purpose, where exactly is it located, and how do I test it? Thanks for the help! -James
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Response
Hello James. Thanks for visiting, writing in, and including a photo. It sometimes makes answering so much easier. If you look at your photo, see where the air line from the piston head turns and runs down to the tank on the left? Usually, the device that connects that air line to the tank opening is a check valve. It’s purpose is to keep the air in the tank as the piston compresses it. The higher pressure air flows down the line, through the check valve, and into the tank.
If this check valve isn’t seating properly, or has failed completely, then air can’t stay in the tank. This may be an issue for your compressor. Best to make sure the tank is empty, the compressor is unplugged, and then disassemble the fittings at the tank, and examine the check valve. It should seal the air in one direction. Reassemble after cleaning (if needed) and see if this makes any difference, OK?
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Looks like a Champion pump
by: Smithereens
Sorry to barge in here, but I saw a lot of posters asking about the pump on the Ward’s unit. That looks to me like a Champion pump, and parts are still available for those. They were used on a variety of brands (Speed Aire, for instance), and they made a million of them, much like the cast iron Campbell Hausfelds. Check with Grainger or Champion – I think you will find the parts. – Mark
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