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by Carlos Rodriguez
(La Mirada, CA. )
My dad just gave me his old CH 6.5 HP (VT627000AJ) air compressor. For some reason he disconnected the motor from the pressure switch and does not remember how to reconnect it.

The motor is a Doerr Emerson Electric motor LR22132 model T368X8NJ1016 MFG # B69B.
There is no wire diagram. On the connecting plate there are only number that read 1,3 and 4 next to some copper poles, There is also poles 2 & 5 that have a jumper that is label L2. The 8 inch cable that connects the pressure switch to the motor has 3 cables, green (ground), white & black.
So with that said I have 3 possible wiring configurations.
1 & 3, 1 & 4 or 3 & 4. I’m thinking 1 & 4 but I would like to be sure.
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Wiring pressure switch
Double darn! Can’t see where the power cord goes, or which terminal is number 3.
No matter, try this, and I’m gonna write some stuff that you may already know : you need some sort of continuity tester or volt-ohm-meter. Any functional cheapo will do.
Start with the switch “OFF”.
The power in a proper outlet (wall plug) is arranged like this
N H
G
(N)eutral is the wide blade slot, white wire.
Connect to the cord blade that fits there, and
test to find that in the switch, then turn the switch to “on” and find the other terminal.
Turn the switch back to “OFF”
Repeat with the (H)ot, blade, black wire.
The wires from the motor go to the second terminal you found, white to white, black to black.
Ground goes to the green or dark ground screw.
If you don’t find a second terminal in the “ON” position, the switch is bad.
If you are unclear what I’m saying above, write again to ask before you try to plug it in.
____________________
Got it
The correct wiring configuration is 1 & 3, is working now, thanks for your help.
_____________________
Got it
Good and You’re welcome.
How to reconnect a snap off terminal connector to a wire? Damage it when screw would nt release at air compressorswitch , to tight when screwed in.
Sounds like you’re talking about a ring terminal. If so, the answer is you don’t. You need to replace it.
Probably your best best is to go to a nearby store that carries electrical stuff with the terminal.
Look around or ask for a kit to replace it. That will include the crimper you’re gonna need.
Practice using it on some scrap wire. (buy a for or two if you don’t already have some).
In a pinch, temporarily, you can just strip the wire a 1/4 inch or so and wrap it around the screw without any connector.
What is the yellow wire for in the above photo. I purchased a new motor. Do I need the jumper wire on the new motor my cord is white black and green
Depends on the motor. Is there not a wiring diagram on the motor or cover plate?
I can say this much, IF it’s dual voltage motor. The jumper above is to wire it for 240V. The wire(s) in a different place would be for 120V. But that’s what the diagram that I mentioned should tell you. If the motor is fixed at 230 or 240V, then just connect it to whatever is marked, or the wires extending out of the case.
I have the same motor as Carlos. I believe a have to change the run and start capacitor, but the start capacitor label is worn out and I can’t see the specifications for the capacitor. Any help would be appreciated.
Unless it’s really old and/or been sitting unused, usually one cap or the other goes. What are your symptoms?
Plug the compressor in and hear nothing from the motor. I have power to the pressure switch and to the motor. I was going to replace the capacitors but the start capacitor label is faded and I cannot read the details on the volts, hertz or micro fharads
It is a 1995 with the doerr 6.5 hp motor. When plugged in the compressor does nothing and no sounds from the motor. The engine and compressor move freely. I have to power to the pressure switch and to the motor
It is a 1995 Campbell Hausfeld compressor. I plug the compressor in and it does nothing. I have power to the pressure switch and to the motor. The engine and compressor move freely. I believe it may be the capacitors. The start capacitors label has worn off and I can not tell the volts, hertz or micro farads. The compressor was given to me free.
Well, if it’s doing nothing, new capacitors will not make a difference. Capacitor problems cause buzzing or blowing the circuit breaker either immediately or after a fairly short time. Your motor should be a 230V unit. If that is so, please check the voltage *across* the motor, not to ground. You should have about 220-240V. If you have zero or 110-120V, your power is not correct. If you do have 220 or so, then the motor is blown, or possibly there is a loose internal connection. Let us know what you find, please, and we can go from there. Or… Read more »
Good news. After checking the power with the pressure switch on it only read .040. My friend suggested looking at the plug. Removed the plug and saw one of the wires was off. Fixed plug and the compressor magically turned on. Pumped up to 120psi and shut off. It seems like everything is working. Thank you for your assistance, it helped out tremendously.
Excellent!
Thanks for letting us know how you fixed it.