Liberty Aux Compressor

[truk4u]

Depending on your vintage, your Liberty Aux Pump has a small filter that should be changed periodically. Mine is tough to get at, just in front of the front axle behind a steel access door only accessed from underneath. Properly jacked and supported of course.

6589
Round black cover just rotates to loosen
6590
Filter with cover removed
6591
Filter

[merle&louise]

Truk,

There is also a check valve that can go bad. It would be a good addition to the spare parts bin. It is not expensive, but when it gives out the pump will running continuously. I changed my filter when the check valve was changed.

[Charles Spera]

Amen to the check valve. Now to go down to the shop and pull the filter.

[BrianE]

You're welcome Tom.

[ToyMan]

Tom,
More great info. Thanks.
Ron

[aggies09]

This thread is proving to be very helpful to this Pogger, but I am now a little confused. Upon reading this post, and having owned my bus now for nearly two years, I decided to go out to the bus barn and pull the aux air filter for replacement. While there, I drained the aux air tank which released a considerable amount of water. As I was releasing the water from the tank a compressor kicked on that is not my aux compressor. It appears to be on top of the aux air tank, but I cannot see it. Are there two aux air compressors? Is there another filter/dryer associated with the tank that I am not seeing, but need to service. I thought there was an article on the aux air system, but didn't see it. Let me hear from the experts on this one. Thanks.

[Jon Wehrenberg]

Tony,

Assuming we have almost the same coach which shares a lot of similarities to Tom's you should only have a single aux air compressor located behind a steel panel you can access from ahead of the steer axle. The panel has 10 or 12 screws and when removed exposes the compressor that is located in a box you can see from the steer compartment door.

If you aux air tank has water in it you either have been running the aux air compressor a lot, or you have a lot of water back upstream in all the air tanks. I would suggest you drain the bowl on the aux air line that is located near the protection valve in the steer compartment. Maybe Tom or someone can post a picture of that because that might be filled with water.

Where you get the sound of another compressor I cannot answer unless you have a comppressor dedicated to a device such as power awnings or a toilet. If that is the case that additional compressor might not even be tied into the aux system.

Over time owners modify the coaches from the way they were originally built so you may have had some modifications.

[garyde]

My aux air compressor can only be accessed by taking the entertainment center out in bay #2 starboard side. There is also a Zip Dee air compressor in th same bay. It runs the zip dee awning only.
There is a seperate on-off switch for it in my port bay #2 side with the inverters, fuses, relays etc.

[aggies09]

Ok. Here is what I think I know. I do have power awnings, so maybe the air tank/reservoir that I drained was for that, and maybe there is a dedicated compressor on top of that tank that I cannot see. However, immediately adjacent to the tank that I drained, which is located in the center of the coach about even with the second bay (entertainment bay), there is a compressor that will turn on when I have my bride switch on the air compressor from inside the coach while I am under the bus. I would think that this would mean that the compressor that I am looking at is my aux compressor. I see no metal box near the front of my coach that would house anything. Tom and Jon, where is your aux air tank located? Maybe there is a similarity there? I haven't found the "bowl on the aux air line", but will continue the hunt. If any of you have pics that would be great.

[aggies09]

Thanks Gary. My deduction is that I must have a separate compressor for the Zip Dee awnings as well. My compressors appear to be in a similar location to yours, but I can access through a panel under the bus. Not easily, I might add. I did find the in line air filter and there was a small amount of water there. I also found a Norgren air filter that produced no fluid. I took that as a good sign. Does your Zip Dee compressor tie into the aux air system or does it have it's own tank?..................Tom, do you have the part number for the filter shown above?

[truk4u]

Tuga - No check valve on my line, goes direct to the filter and pressure protection valve in the steering bay.

Brian - Thank you for the filters. Now where is my Liberty Jacket?:p

Tony - I'm out of town without the bus and don't have the part number, but I can get it to you by next weekend if your not in a hurry. My aux tank is next to the secondary tank in the general area above the front axle.

[aggies09]

Thanks Tom. I am not going anywhere for a month so I have time. Thanks for the post and the help.

[JIM CHALOUPKA]

Not all buses have this filter.

Open the brass T valve to drain through the small hose.

If you have it rebuild it. Prevost has the parts.

[aggies09]

Jim, the brass T Valve as shown has been replaced with a Norgren T Valve on my bus. Thanks for the photos, they are extremely helpful as I piece together how my system works.

[garyde]

Hi Tony. The zip dee air compressor is independant from the aux. air system. The two air systems are not connected. I hope your not getting under your coach without supporting the Coach.

[aggies09]

FYI. The part for this was for a Gast compressor, part number B344A.

I hope all of you have a great Memorial Day weekend. Thanks to all who have served our country.