Community Forums

jimloeh · 09-18-2018, 12:06 PM

Hello all. Just started to notice after parking our 05 Monaco Diplomat after about a week or so it starts sagging on passenger side. If I fire it up build air up its fine and driving it theres no problem. I also don't dump the air. Any Ideas would be greatly appreciated. Jim

BFlinn181 · 09-18-2018, 12:17 PM

I'd guess you have a leak. Start painting the air spring and air lines with soapy water and look for bubbles. You could also take to a truck garage and see if they have an ultrasonic 'sniffer' that can detect leaks.

CountryB · 09-21-2018, 03:49 PM

What Bob said --
It's not too uncommon to find air leaks in these older coaches. Usually multiple leaks.
The air bags, ride-height-valve, and/or lines connecting those together can leak. Also if you have the air leveling system (i.e. HWH) there is a "Travel" valve/manifold in the mix that can also leak.

The airbags are sort of an isolated inner circle in the air system. meaning that they are protected with check valves from the rest of the air system, so usually one will find the coach's air tanks are empty but the airbags are still hold air.

Of course this is not the case in your situation. but at least the (air bag) leak is going to be isolated to a small area near the affected air bag.

hypoxia · 09-22-2018, 06:56 AM

As advised above, do a leak check with soap solution. That probably won't show any internal valve leaks though. I like to get gas leak detector which I mix with water to thin it and put it in a spray bottle. https://www.homedepot.com/p/8-oz-All...2092/100151681

If you are mechanical the quick and easy first step is replace the ride height valve on the side that sags. They are about $25 at any truck parts store.

jsmmonaco · 09-22-2018, 07:03 AM

07 monaco knight..............after 7 days it starts to sag on the right side...........have had everything checked, nothing found............pumps back up when coach starts.............stays up for 7 days..............we have learned to live with it....................

CountryB · 09-23-2018, 02:35 PM

Quote:

Originally Posted by jsmmonaco

07 monaco knight..............after 7 days it starts to sag on the right side...........have had everything checked, nothing found............pumps back up when coach starts.............stays up for 7 days..............we have learned to live with it....................

It's probably the ride valve leaking internally - letting air leak out of the airbag through the valve and back into the air tank (which, at this time, is lower on air then the airbag).

jimloeh · 09-24-2018, 04:25 AM

Thanks for the info. I will try spraying and see where it takes me.

BFlinn181 · 09-24-2018, 08:48 AM

If it takes a "week or so" to bleed down enough to make the RV tilt, you might just dump air when parking. It'll make the steps easier to climb!

P38 · 09-26-2018, 07:42 PM

Quote:

Originally Posted by jsmmonaco

07 monaco knight..............after 7 days it starts to sag on the right side...........have had everything checked, nothing found............pumps back up when coach starts.............stays up for 7 days..............we have learned to live with it....................

2004 Diplomat. Learned to live with it also. Just dump the air whereever I park it.

Letsgoagain · 03-26-2019, 05:42 PM

Quote:

Originally Posted by hypoxia

As advised above, do a leak check with soap solution. That probably won't show any internal valve leaks though. I like to get gas leak detector which I mix with water to thin it and put it in a spray bottle. https://www.homedepot.com/p/8-oz-All...2092/100151681

If you are mechanical the quick and easy first step is replace the ride height valve on the side that sags. They are about $25 at any truck parts store.

Hello, would you happen to know the part # for the ride height valve. I'm having the same problem with the motorhome sagging on the passenger side back after a few days. Thought maybe I would just change the valve as you suggested.
I crawled under there a couple of days ago and sprayed everything I could with a soapy water solution but didn't find any leaks.
While traveling the air system will recharge usually about every 25 miles. Of
course this depends a lot on how much the motorhome tries to stay level according to road conditions.
Appreciate the info if you know the part #.
Thanks

BFlinn181 · 03-26-2019, 06:04 PM

Quote:

Originally Posted by Letsgoagain

Hello, would you happen to know the part # for the ride height valve. I'm having the same problem with the motorhome sagging on the passenger side back after a few days. Thought maybe I would just change the valve as you suggested.
I crawled under there a couple of days ago and sprayed everything I could with a soapy water solution but didn't find any leaks.
While traveling the air system will recharge usually about every 25 miles. Of
course this depends a lot on how much the motorhome tries to stay level according to road conditions.
Appreciate the info if you know the part #.
Thanks

Some air suspension systems use a manifold that is prone to leaking, also hoses or connections could be the culprit. Just throwing parts at the problem can be expensive and time consuming before you identify the real source of the leak.

Your description of "air system will recharge usually about every 25 miles" I guess you're talking about a separate electric air compressor? Are you sure your system has ride-height valves? If you do, check that the linkage between the frame and axle is tight and adjusted before just replacing parts.

I really wouldn't take the word of someone else's part number, I've had best success on removing the ride height valve (or any other item I want to replace) and taking it to the parts counter to match up the proper part.

Windecker · 03-30-2019, 07:26 PM

Back or front lean?

Ride height valve is attached to a rod that goes to left and right side rear axle, straight up to a left and right valves. Rod is maybe 14 inches (guessing) front only has one valve, is attached to the front axle in the center. Same rod attaches to the valve in front like the rear.

Air the coach, shut down, soap test the ride height valves. My experience has shown valves leaking out the discharge rubber tube on the valve.
Could leak anywhere on the valve I suppose but path of least resistances...

I agree with not replacing valves unless there is a "reason".

If you have HWH air level which I assume you do, I would check 6 pack valves with soap. They are prone to leak and are easy to fix on your own.

Do your air tanks bleed off also while sitting?

Windecker.

Letsgoagain · 05-08-2019, 08:52 PM

Quote:

Originally Posted by Windecker

Back or front lean?

Ride height valve is attached to a rod that goes to left and right side rear axle, straight up to a left and right valves. Rod is maybe 14 inches (guessing) front only has one valve, is attached to the front axle in the center. Same rod attaches to the valve in front like the rear.

Air the coach, shut down, soap test the ride height valves. My experience has shown valves leaking out the discharge rubber tube on the valve.
Could leak anywhere on the valve I suppose but path of least resistances...

I agree with not replacing valves unless there is a "reason".

If you have HWH air level which I assume you do, I would check 6 pack valves with soap. They are prone to leak and are easy to fix on your own.
Windecker,

Do your air tanks bleed off also while sitting?

Windecker.

Windecker,
Been a while since I've been on this site. Still having the sagging rear passenger side issue.
I appreciate your response and will try to give a little more information.
The air tanks do bleed down after sitting. I would say after a week or so both the front and rear air tank have bled down to 30 psi.
I have tried to soap the passenger side rear air bag, lines, and leveling valve looking and listening for any sign of air leakage. Access to visually see the leveling valve is very difficult. Had to crawl under just in front of the passenger rear tire and stretch with a mirror held out to top of wheel well to see the valve. Didn't see any bubbles after spraying with soap water mixture.
I'm not sure if the leveling system is HWH or not but I'm not familiar with the term 6 pack so I may not have that system. This is a four air bag RR4R roadmaster chassis. Two air leveling valves in the back and one in front.
Last week I changed out the air dryer desiccant filter cartridge and soap sprayed all connecting air lines at the dryer looking for leaks but found none.
Feel like the leak has to be at the passenger rear side since it is the area that is first to start sagging and as you said may be the exhaust side but I sure as heck can't find it, can't visibly detect it.
On my last trip I was watching the air gauges pretty closely to determine how long it would take the tanks to bleed down until the system would refill the tanks to 125 psi. I was measuring it in miles driven which ended up being approx. 30 miles until it dropped to 95 psi.
Of course this was on Florida interstate 95 between Jupiter and Palm Bay which is about as good and smooth a road as you will find anywhere in the U.S. So not much adjustment of the air bags going on.
Once again I thank you for your reply.

grthigpen · 10-04-2019, 07:16 AM

For a little tidbit... I have a 2003 HR Endeavor...it will start to sag on the curb side after i have been in and out of it a few times after parking it. So I checked it out. What happens is, being a heavy person, when i get out of the bus and hit the ground, the bus rocks up some and goes beyond the center point of the ride height valve and i can hear it bleed a little air out of the right front bags. After a few times in and out, its sagging. If i don't keep going in and out after shut down, it stays at its ride height setting......just a little tidbit on mine.