dresser wayne compressor trying to fix

[generalsparky]

So I replaced the pressure control switch but it gets to 120 psi and then the switch releases air, from safety valve I think. Won't stop until it releases a lot of air almost all of it. The old switch did the same thing. Not sure what's going on. I did some research i thought maybe it was the unloader stuck open but that's not on the switch is it? There's also some box on the pump with a electric plug don't know what that does, temp gauge maybe? I don't know much about these 2 stagers very clueless. Maybe I should buy a new oil-less and just use the tank?

 

[The Cobbler]

sounds like a blow off safety valve is popping. it's not part of the switch, it would be separate , on the tank . it is designed to blow off when excessive pressure is reached . are you sure the pressure is 125, is the gauge accurate?
snap some pics of this box with a plug on it

 

[MacMcMacmac]

The unloader valve is in the switch most likely. Sounds like your check valve has failed and all of the air is being blown down at shutoff.

 

[generalsparky]

The unloader valve is in the switch most likely. Sounds like your check valve has failed and all of the air is being blown down at shutoff.

Thanks, does that mean I need a new switch?

 

[generalsparky]

sounds like a blow off safety valve is popping. it's not part of the switch, it would be separate , on the tank . it is designed to blow off when excessive pressure is reached . are you sure the pressure is 125, is the gauge accurate?
snap some pics of this box with a plug on it

 

[generalsparky]

sounds like a blow off safety valve is popping. it's not part of the switch, it would be separate , on the tank . it is designed to blow off when excessive pressure is reached . are you sure the pressure is 125, is the gauge accurate?
snap some pics of this box with a plug on it

when it goes off i see a spark on the control switch and it lets out air, but both switches failing same way and 1 is brand new. Just blows my mind.

 

[RTM]

On my little compressor, the unloader is part of the pressure switch. I would agree with Mac that the check valve seems to be the problem. The unloader only releases the air between the compressor head and the check valve, if I read the threads here correctly.

 

[MacMcMacmac]

I have no idea what this is. It almost looks like a Klixon overload switch from a refrigeration compressor glued onto the side of your pump.

It's normal for contacts to spark when they disconnect under load. If there are little sparks flying everywhere and bits of slag like a welding arc, then I would be worried. I have no idea what this switch in the picture might be doing, or supposed to be doing. The red button on the motor is for a thermal overload reset, so I don't know why this extra switch is in the mix, unless it is substituting for a failed thermal overload in the motor. It's certainly not a low oil level switch, since there is so little oil in these Campbell Hausfeld VT pumps it would likely not have enough range to be useful.

 

[generalsparky]

On my little compressor, the unloader is part of the pressure switch. I would agree with Mac that the check valve seems to be the problem. The unloader only releases the air between the compressor head and the check valve, if I read the threads here correctly.

Check valve, umm, not sure what that is. Researching... Uh, I think it maybe this submarine looking thing the pressure control switch screws into?

 

[generalsparky]

Is it what I circled here? Or maybe at the bottom of it? Know where I can buy a replacement? Is this it? https://www.amazon.com/dp/B00NU50ZPM/?tag=atomicindus08-20 I guess I need to take it all apart to make sure I'm getting the right size fittings/ends.

 

[RTM]

This is complete guess cuz I can't pretend to be a compressor expert.

Looking at your away shot it looks like the copper pipe that you circled comes out of the compressor head. I don't see any other fittings on that line. I would say that somewhere between where you circled and the tank is where the check valve should be. I can't see what is below the deck that you circled.


As far as size goes, yeah verify inlets and outlets and every other different thing before you buy.

 

[generalsparky]

This is complete guess cuz I can't pretend to be a compressor expert.

Looking at your away shot it looks like the copper pipe that you circled comes out of the compressor head. I don't see any other fittings on that line. I would say that somewhere between where you circled and the tank is where the check valve should be. I can't see what is below the deck that you circled.


As far as size goes, yeah verify inlets and outlets and every other different thing before you buy.

Thanks for everyone's advice. I'll replace the check valve and report back.

 

[generalsparky]

It's working great now. Fills the whole 100gal tank to 120psi in about 3min. Thanks for your help I was really stuck. I searched online for help for weeks before I came here.
I do need to tension the belt, is there an easy way to do that? I tried unbolting the electric motor and stuff but I can't seem to get the tension high enough. Man, it's frustrating.

 

[mogandave]

Belts do not have to be very tight. Are they slipping?

Does the motor mount not have slots?

 

[generalsparky]

Belts do not have to be very tight. Are they slipping?

Does the motor mount not have slots?

No, i guess it's fine. It's not slipping, but it kinda bouncing a bit. It might stop when I bolt it to the ground. Yeah, there are slots, so do you take the belt off and then move it or do you move it with the belt on?

 

[mogandave]

No, i guess it's fine. It's not slipping, but it kinda bouncing a bit. It might stop when I bolt it to the ground. Yeah, there are slots, so do you take the belt off and then move it or do you move it with the belt on?

Just move it with the belts on.

Make sure the motor pully is in line with the compressor pully.

You can probably use a pinch-bar/board/pipe to snug it back a little, but not too tight.

 

[mogandave]

Installing/removing belts without moving the motor is generally not a good idea.