Air compressor govnor problem

Bob Gil · August 25, 2008, 03:18:45 PM

I did not have a governor on this bus, thanks to the person that did not know what they were doing trying to fix the fire damage before I got it.

I installed one this afternoon but I can't seam to get it to do any thing?

Let me go over what I did and see if it sounds correct to you.

I put the line from the air tank to the res side of the gov. the the unload side to the compressor. I did not attach any thing to the exhaust port and I did not plug it either I left it open. I did plug the other res and unload ports that I was not using, and i did not have any air leaks that I could tell. But it still built up 130 lbs and the popoff let the air out and the compressor never stopped building air.

Any ideas what could be the problem?

niles500 · August 25, 2008, 03:28:44 PM

Probably the unloaders in the Comp. - HTH

makemineatwostroke · August 25, 2008, 03:32:34 PM

Bob if you have a air dryer it hooks up to that not the tank

Bob Gil · August 25, 2008, 03:53:41 PM

Too old a bus no air dryer.

Busted Knuckle · August 25, 2008, 05:22:04 PM

What Niles said! The unloaders in the compressor are probably stuck or bad! It's been ages since I changed any, but there used to be a "unloader kit" available at just about any parts store. But I recently asked about one while I was at a DD dealership for other parts. They told me "GOOD LUCK nobody replaces unloader valves these days, we just change out the compressor!" Hmmp OK I guess mine will just spit more often than normal until I find an unloader kit or the compressor goes bad!

BK

FWIW; By the way check around your area in the small truck repair shops someone may still have a kit to get rid of on the shelf.

Brian Diehl · August 25, 2008, 08:10:42 PM

There is one more option .... Is the govenor new? It may need to be adjusted for max pressure. There is an adjustment screw inside the plastic end cap. Maybe try adjusting that before blaming the compressor. Also, to determine if the compressor is working "A-okay" just hookup some shop air to the air compressor unloader port and make sure the compressor stops building air. If it doesn't, then you know the unloaders are bad. Just some ideas ...

gus · August 25, 2008, 08:57:10 PM

What Brian said plus;

The pop off valve shouldn't. Your pressure is set too high, it shouldn't be over 110-120 max.

Remove the black plastic cap, loosen the lock nut and turn the center screw CW until you get no more that105-110 psi. CW to decrease max press is against all logic to me but that is the way it works.

It won't take more than a turn or two to do this as I remember since it has been a while since I adjusted mine.

Once you get the bus on the road carry a spare. They are only $20 and if one goes bad you may have 150 psi before you know it-don't ask me how I know!

Busted Knuckle · August 25, 2008, 08:57:43 PM

Quote from: Brian Diehl on August 25, 2008, 08:10:42 PM
There is one more option .... Is the govenor new? It may need to be adjusted for max pressure. There is an adjustment screw inside the plastic end cap. Maybe try adjusting that before blaming the compressor. Also, to determine if the compressor is working "A-okay" just hookup some shop air to the air compressor unloader port and make sure the compressor stops building air. If it doesn't, then you know the unloaders are bad. Just some ideas ...

Yeah Brian your right I did skip that part, I do the no-no and assumed he'd already been there!

Bob Gil · August 25, 2008, 11:56:56 PM

I though that i posted that I tried to adjust the govoner both ways and nothing helped.

I will see if I am getting air to the compressor from the govnor if I am I may try some WD-40 in it, if that does not help I will see if I can find an unloader kit for it.

Thanks

Bob

buswarrior · August 26, 2008, 09:42:44 AM

Gus, it's clockwise, because you are tightening the spring against which the air pressure pushes. Stronger the spring, the lower the air pressure it can defeat, doing it's thing at a lower air pressure than first set.

clear as mud.

happy coaching!
buswarrior

makemineatwostroke · August 26, 2008, 09:58:59 AM

Bob, a lot of the old belt driven compressors did not have a governor that bolted on to the compressers but a remote type can you post a photo of what you have and maybe we can help I think you have installed a governor on a compressor that doesn't have one

Lin · August 26, 2008, 10:37:50 AM

Posted on this thread in error. Moved!

Bob Gil · August 26, 2008, 10:41:46 AM

My air compressor is direct drive off the rear of the DD engine.

I will see if I can get a picture of it on the engine but here is a picture of one just like it. You can see the governor remote In line coming off the right side of it.

I have looked it up on the Bendix web site and it shows the governor mounted on the back side from where it mounts to the engine. My engine sets too close to the fire wall for it to mount there so it is remote mounted on the fire wall.

I have never heard of an air system that did not have a governor on it of some kind.

makemineatwostroke · August 26, 2008, 11:13:31 AM

Not trying to tell you they do not have governors just that they are not always on the compressor and some compressors of old just have a line fitting for the governor.and if they are not plumbed right to the port of the governor it will not unload have a great day

Bob Gil · August 26, 2008, 11:27:28 AM

Quote from: makemineatwostroke on August 26, 2008, 11:13:31 AM
Not trying to tell you they do not have governors just that they are not always on the compressor and some compressors of old just have a line fitting for the governor.and if they are not plumbed right to the port of the governor it will not unload have a great day

ok I understand what you are saying. I think mine should be plumbed correctly. If you will notice in the picture I posted before the govnoer is mounted on the right side of the compressor. If you will look at these pictures of mine it has a hose at that location that goes to the unloading port on the govnorer. There is not enough room to mount the govnoer in my bus.