Shop air compressor wont put out more than 110 PSI

[Pete Masterson]

I started out with a cheap compressor much like the one you describe -- it was able to get to 120 psi -- but after a few weeks it failed -- since I bought it at Costco, they took it back with a full credit as defective (under the 1 year warranty).

I then bought a 150 psi (max) Rigid-brand "contractors, 4.5 gal, twin stack" compressor from Home Depot. It has proved to be much more reliable.

The compressor (may have) two pressure dials and a pressure regulator control knob. This allows you to set the maximum output pressure (to the hose) If the regulator is dialed back a little bit, it may not let the compressor reach maximum pressure.

The size/type of output hose should not affect the maximum pressure -- but a smaller hose will reduce the throughput (volume) of air. So filling will take longer and some air-operated tools may not get adequate volume of air at a given pressure. I use a 50' 3/8" hose. It does just fine for my bus tires and the few air operated tools I have, including a 1/2" impact wrench. (I bought one that's more efficient (and expensive) in its required air volume through the tool.)

I have one of those vinyl coiled hoses, it's 1/4" -- I've only used it with my auto tires that only need 32 psi.

When filling the bus tires, it's usually best to let the compressor cycle on to achieve the maximum pressure. Admittedly, the 150 psi rated compressor I use has a little more oomph and has less trouble getting to 120 psi -- but air delivery (volume) is slower at the higher pressure, so it can take several minutes to get the last few pounds of pressure into the tires.

Some compressors (check the manual) have a maximum cycle time limit (say, 25%) if so, be careful to stop and let the compressor rest from time to time so you don't overheat it.

Pete Masterson

'95 Blue Bird Wanderlodge WBDA 42 (SOLD!)

El Sobrante CA

"aeonix1@mac.com"

On Sep 21, 2009, at 1:52 PM, wl89spman wrote:

My Porter Cable 135PSI 3HP/4GAL wont put out more than 110psi with 50'rubber hose or 30' coiled yellow vinal(I think). It has always been this way since new. No leaks or problems...My new Michlens need 120 psi so now I have to do something. What psi compressor does everybody use?
Is there a compressor expert here? Does the length and composition of the hose matter? If so what length and material hose do I need for my 135 psi compressor?The output gauge on the compressor reads 130psi but wont pump up tires past 110psi...
Ant help would be appreciated.

Ed Gardels 89SP
Arlington Tx