Air compressor problems

[Explosia]

My air compressor keeps building pressure to about 145 and then I hear the pressure released and drops back down to 120. Then it builds back up and this cycle repeats. I guess the governor needs to be replaced?

[Waterloo]

What are you driving? Sometimes it is just easier and cheaper to replace the entire air dryer. Do you replace the filter once or twice a year?

[Lonestar10]

governor might be sticking or set to high i think...my truck fills to 120 chuffs its puff of air and doesnt kick back in again till around 100lbs but it doesnt drop to 100 unless i use the brakes or something else air related.

[RyanC]

If you are getting a big pressure release, start the truck and look/crawl underneath it is probably the safety pressure relief valve on your primary air tank opening. This opens at 140 to 150 psi so you don't over pressure the system. If that is where your air is coming from that's good because that's working properly.

But.... your compressor is never being told to shut off so it is constantly pumping air. It would most likely be the governor but start by disconnecting the lines to the governor and blowing them out with air. Take your desiccant filter off and look down into the housing and see if there is any sludge or debris build up in the bottom of housing.

Basically your doing a little more thorough visual inspection and blowing the lines out to make sure everything is open and clean before replacing the governor. Plugged supply lines and or ports will give you same results as a bad governor. Also if there's sludge in the bottom of desiccant housing it's in the governor also.

[Explosia]

Thanks for the help, the last time I had checked this thread no one had replied, and I’m just now back in the board. I knew my compressor was constantly running and the safety valve was working. I thought it was the governor, but wasn’t sure. I have limited mechanical skills, so pulled off at the Petro in Laramie just in case. I immediately saw a loose air hose and a broken brass fitting, and repaired it myself. It was Sunday, and the Petro didn’t have the right piece, but the loves across the street did.

[Lonestar10]

i think that might be the unloader air line for when everything reaches pressure.

[Nilao]

yup, I agree. That's the unloader line to the head in the compressor...governor may be telling it to stop pumping but it isn't receiving the signal.