Aux Air Pressure?

[dreamchasers]

What Aux Air pressure does most use when the coach is parked? For example, when the coach engine is not running and the coach is parked. What aux air pressure does the air compressor come on and off?

Mine seems to come on at ~80 and off at ~100 psi.

Hector

[phorner]

Hector,

Mine is similar..... on at 60 off at 90.

That being said, we only need aux air while parked to operate the bed lift.

And, of course, airing up the occasional bicycle tire

[truk4u]

Hector,

60/100 for toilet only.

[Jon Wehrenberg]

I have backed mine down to on at 40, off at 80.

At the lower pressures the pump doesn't work as hard yet everything still works, doors, bed lift, door lock, floor slide (not needed, but it still works) generator air bags, and dump valve.

[Reagan Sirmons]

Guys,
I could not figure out how to start a new subject so I hope this gets posted on this old thread. For those who might note my posts are more regular over the last 60 days...this is what happens when a AAA personality ends up with half a day every day at present free to tinker...
Here goes: When I turn the ignition key to the "on" position, there is a distinct hissing sound coming from the right side drive axle area. When I turn "off" the key, it stops. I can run the engine and turn off the key and there is no escaping air. HOWEVER, when I turn the ignition key to "on" and the hissing begins, I can reach up to the Country Coach installed leveling device high on the front ceiling and turn it on...the hissing then stops immediately. The leveling device switch, when activated, shuts the escaping air off. If the air is allowed to escape, the air pressure in the on board air compressor declines.
The coach does not have any leaking air bags and the selector switch on the left panel is in the correct position. ... what does anyone think is causing the hissing escaping air when I turn the key on? Is there a leveling device at this location? I am not about to get under this thing to look even though I have bus blocks. Something tells me that potentially varying air pressure and weight do not mix well.
Thanks for your thoughts.
Pres

[Gil_J]

Reagan,

First, congrats on the free time!

When the key is off the air bags are sealed from the rest on the bus' air system. When you turn the key on the bags are being controlled by the ride height valves. When the key is on your HWH leveling system goes into "drive" mode, which puts the Prevost system in control. With the key on you can turn on the HWH level system which takes control of the bags and takes the ride height adjusters out of the picture. So, your symptoms suggest the hissing could be from the ride height valve. If so, let the coach get to ride height and see if the hissing goes away.

You should be able to reach in front of the drive tires and feel the air coming from the valve, if this is the leak. Here's what it looks like. The hose aimed straight down is attached to the exhaust port and would be were it's leaking, if it's the internal piston and o-ring that is leaking. You should be able to safely do this without getting under the bus.


Ride Height Valve.jpg

[Reagan Sirmons]

Gil,
Absolutely great! I will test this tomorrow. That has to be where the hissing is originating.
I at least know what I am looking for... I changed these out on the '87 Newell I totally rebuilt in 2004... at least I have the idea.
Thanks a lot for your kind response. Where do you guys live? Is it in a warmer climate? ... we are in Houston and had some cold weather for us last night...
it delayed the tee times this morning...
Best,
Reagan

[Gil_J]

Houston, and Texas in general, seems to have gotten colder the last couple of years.

I'm on Florida's Nature Coast, about 75 miles north of Tampa. So far, the whether has been good, but there were a couple of morning in the past few weeks weer we hit 40 degrees. The good news here is if it gets too cold we can drive south. Unless you want to cross the border, you don't have too much more south left.

[Reagan Sirmons]

Gil, I just went to the coach and for the first time ever, the coach was leaning to the left. I cranked the coach and let it run for 5 minutes. I then cut the engine off ... no leak....at least one that I could hear..... I then turned on the key and the hissing began. I found both ride adjustment valves and neither one is leaking. The leaking is very pronounced and is coming from somewhere between the two sets of air bags (starboard and port) If I could guess, it is midway or is closer to the port side ...the side to which the bus was leaning. There seems to be a couple of chambers under there... I definitely could not tell for sure but it is as if there is an open valve....so its a big escaping amount of air. Tomorrow, I am taking the coach to a truck shop that has a long pit under the coach. I will then be able to see exactly where the air is coming from. It is so pronounced that it will be very evident, I am certain. I just cannot see the source without getting under this thing and that's not going to happen while it's in the warehouse.
If you have any thoughts for my search, I will listen intently but for now...I will have to wait until tomorrow. I may be wrong but neither of the air bags seem to be a part of this problem even though the air finally went down on one side for the first time ever.
Thank you again...
By the way, we can go 200 miles South of here and never be out of Texas.
Nonetheless, I was talking to some people today from Tampa... I have a relationship with a group there... we meet in Sarasota on occasion... if we meet any time soon, I will bring the coach and we might get together.
Very best... I will keep you posted on the mystery leak but let me know your thoughts if any.
Pres

[Reagan Sirmons]

Took the coach to a shop and put it on a rack. In front of the over-the-road evaporator coil of the Country Coach installation which hangs down between the drive axle tires on the drive axle, there is a support beam going across the coach. Attached to the wall forward of the beam and opposite the evaporator coil is a valve with three or four hoses connected to it. Two of the hoses go out the bottom and curl upward through a "gathering" of other hoses and electrical wires. One of these has the hole in it. I assume these go to the front to the air compressor but am not certain. Above the valve and out of reach...as the hoses go to the gathered hoses and wires, the two hoses from the valve are clamped together by a plastic tie down that has worked a hole into the hose itself. The air escaping is prolific with the key turned on but stops if I engage the CC leveling system. Once the coach stops and the engine is off, the air doe not escape. I, of course, assume that the air is escaping while the engine is running but for obvious reasons of noise and vibrations could not tell. I assume I will call the CC folks who represent that they can advise CC owners for a fee. I certainly think they would be the ones to tell me if the hoses go to the compressor..... that is at least twenty two feet forward of the valve. My only thought at this time is to determine if these two hoses go all the way and if new hoses attached to them could be pulled through the portals. The answer is no if they are clamped anywhere along the way.


bottom of valve assembly rear.jpghole in hose going.jpg

The picture on the left is looking up from the bottom. The hose with the hole in it comes off of the bottom (blue in appearance here) and goes directly above the valve about 16 to 18 inches before it goes out of sight as can be seen in the second picture. The picture on the right shows the actual hole (the black area). This also shows the gathering area I was describing. . It is a hard, hard thing to get to. I could not reach it even standing with my shoulder up against the support beam. Are these wires reachable from any other area?
Very interesting situation. It seems that these hoses were put in place and this coach built around them. I wonder if these hoses go through the area where the water heaters are and could be reached if I took off the panels?

Thanks to all who have been following this.
Pres