Community Forums

davidpiano · 04-17-2023, 10:05 AM

Hello, would anyone be able to offer advice regarding 2002 holiday rambler / Monaco motorhome diesel pusher with uneven airbags?
I have searched for leaks, and only found one that is extremely small. Front right bags will not fill at all and rear right bags fill half way. Bags on left side seem full.

Pressure gauge needles both read 100 psi but after air dump red needle goes all the way down to 30 psi and green needle only drops to 90 but all bags are clearly empty.

I have spent hours under the coach, looking at all connections and valves that seem to be working properly. I have blown through all airlines and do not feel any restriction except for the front airline that leaves the passenger side airbags and goes to the front of the coach, but not sure where it goes.

I am now looking in the front compartment in front of the drivers wheel where the fuse panel is.

Trying to find diagrams of that compartment to see where a valve or solenoid for airbags could be.

thank you in advance for any suggestions.

Also, I do not have any power coming to what looks like one of the airline solenoids. I’m not sure where that power would be coming from.
(house, batteries or chassis batteries)

(the first picture below is the solenoid not getting any power. The other pictures are plugs that have nothing connected to them and I do not know what they are for the wondering if they might have something to do with the problem)

twinboat · 04-17-2023, 10:41 AM

Air bags are ride active. There will be 3 or 4 ride height control valves. They adjust while on the road.

Sometimes 2 rears and I front, others 1 rear 2 fronts and others on all 4 corners.

The bags don't fill, they partial fill until the chassis is at ride height. There are point that you measure the gap to set the ride height.

The valves are mechanical with adjustable rods from the chassis mounted valves to the axles.

Take care messing with them because you could let air out of one and get crushed.

Any pressure on the gauges is tank pressures for the brakes, nothing to do with air bags except supply air for them.

shootist · 04-17-2023, 11:26 AM

Put some jumpers on the solenoid you unhooked and see what happens when it is powered up. Find the voltage rating on it first , should be 12v but you never know.

JaminSamin · 04-17-2023, 11:36 AM

The first picture is most likely the air horn solenoid, only getting power when the horn is called for.

Pictures two and three are probably for optional equipment that your unit did not come with. I have several of these unused plugs on my Horizon.

Picture four is an OBD diagnostic port. Some units have two of these, one under the dash near the drivers foot well and one outside near the engine compartment.

Tha_Rooster · 04-17-2023, 01:51 PM

Quote:

Originally Posted by davidpiano

Hello, would anyone be able to offer advice regarding 2002 holiday rambler / Monaco motorhome diesel pusher with uneven airbags?

I have searched for leaks, and only found one that is extremely small. Front right bags will not fill at all and rear right bags fill half way. Bags on left side seem full.

Pressure gauge needles both read 100 psi but after air dump red needle goes all the way down to 30 psi and green needle only drops to 90 but all bags are clearly empty.

I have spent hours under the coach, looking at all connections and valves that seem to be working properly. I have blown through all airlines and do not feel any restriction except for the front airline that leaves the passenger side airbags and goes to the front of the coach, but not sure where it goes.

I am now looking in the front compartment in front of the drivers wheel where the fuse panel is.

Trying to find diagrams of that compartment to see where a valve or solenoid for airbags could be.

thank you in advance for any suggestions.

Also, I do not have any power coming to what looks like one of the airline solenoids. I’m not sure where that power would be coming from.

(house, batteries or chassis batteries)

(the first picture below is the solenoid not getting any power. The other pictures are plugs that have nothing connected to them and I do not know what they are for the wondering if they might have something to do with the problem)

Does it not have ride height air valves like other manufacturers?

jacwjames · 04-17-2023, 02:20 PM

On my rig (manual jacks, no auto air leveling) there are two types of valves the control the height of the RV.

On is the air dump valves like this https://mpparts.com/part/mac-225b-60...ve-225b601baaa

I have one in the front that dumps all 4 of these air bags this is located on the firewall , and two in the rear that dump the rear air bags, these are located at the rear of the coach mounted on steel near the engine. These are controlled by the Air Dump switch located on my dash and also by the hydraulic jack system which starts dumping air as soon as I activate the system.
The second type of air valve is the level control for ride height, these are mechanical type valve that are mounted above each axle, one in the front and two in the rear. It looks like this https://www.amazon.com/Hadley-H00450.../dp/B009RTLS3S

If your motor home is sitting uneven chances are the ride height valve needs to be adjusted. In your manual there should be a good writeup on how to adjust. There is not a standard height, it is model/year specific and it should be listed in the manual. If you don't have a manual you can get one here. https://www.monacocoach.com/service-and-repairs/

What I did when I check/adjusted mine I cut a piece of wood the right length and then used it to measure to make the adjustment, a lot easier they trying to use a tape measure. My front and rear ride heights are different.