Need help ~ no air in paint sprayer


(bancroft ontario)

I have a 2 horse motor on a 40 gallon tank and it builds up pressure 115psi on tank and regulator but cant get my paint gun to spray


not sure what the trouble is as it was homemade made from a mastercraft compressor and all the parts mainly just added a bigger tank as the old one had a hole in it

ps please get back to me at nighthawk_178@hotmail.com with any help ty

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Bill says...

If there is air in the tank, the upstream gauge shows pressure, the regulator gauge shows 115 PSI pressure too, then there is air getting to the regulator.

Assuming that you had air coming out of the compressor to your paint gun before (is this so?) then something has changed.

It were me, I'd turn the pressure down to about 7 PSI on the regulator first.

Then I would look inside the discharge coupler.

With safety goggles on please), and again, very carefully, I would insert a small blunt object (pencil perhaps) to try to unseat the ball check inside the coupler at the back of it. Does air flow out when you do this?

If so, you now know that air is getting out of your air compressor properly, and assuming that you air line connector fits the coupler properly, you will have air flow into your air line.

Disconnect the coupler from the spray gun connector, and again, very carefully, push the ball check inside the coupler at the end of the air line to see if air bleeds out. If yes, the problem is in the valve in your gun.

I'm not a paint gun specialist, but if it is the gun, then I suspect it wasn't properly cleaned last use, and paint has gummed up the works.

Good luck.

Bill


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Constant running then bleeding

by Roger
(USA)

I have a pit bull air compressor. It has 2 two gallon tanks, 2.5 hp motor, 7.5 cfm and the model number is TD-2516T. It had been sitting in my dads barn for around 4-5 years not being used so i decided to take it to my place. Anyways, sometimes the compressor will fill to around 120psi and then bleed air very fast down to around 90 psi then it will start to refill back up to 120psi. It will keep bleeding and refilling as long as it is on, however sometimes it fills to 120psi and holds pressure like its suppose to. Any idea what the problem is? Does the pressure switch need to be replaced?

Thank you very much.

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Bill says...

Hi Roger:

I doubt very much if it's your pressure switch, based on what you've said.

My guess is that your check valve isn't seating properly, and the air is bleeding back out of the tank almost as fast as your compressor pumps it into the tank.

Sometimes the check valve will seat, and when that happens, your tank stays full.

Check out "Check Valves" from the Valves page for more info on what and where they are.

Unplug your compressor, drain the air down to zero, leave the tanks drain valve open, remove and clean / examine the check valve and see if that helps.

Cheers,

Bill

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System relief valve lifts upon start up

A relief valve is installed in the piping system and has been checked for proper setting and operation, every thing fine there.

However, it lifts upon start up of compressor and continues to lift even though system presuure has not had time to build up. The tank is blown down to 0 psi.

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Bill says...

If the PRV opens on startup, with no pressure in the system, then everything is not all right there.

My first response is that the PRV valve itself is at fault. It works on pressure, and the internal operator is such that it won't open the PRV to drain the system until the pressure in the system is way beyond normal cut out pressure. Therefore, if the PRV is opening too soon, it's got a problem.

Bill

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