MH Air Suspension leaking and body dropping

[terboggs]

Every week my rv slowly lowers itself, i notice it esp at the door step as it get lower to the growd ,Is that normal? Monoco Exec 2001

[Ivan K]

Do you have air leveling or jacks or both, do you leave it in Auto, are you on level ground or severely unlevel? You would get better answers if you describe it closer. The generic answer would be that you have minor leaks if it takes a week.

[Guest Ray Davis]

I wouldn't say it's normal but it's common.  They were not designed to leak, however, most coaches do leak to some extent.      And if it's going down evenly, not one corner going down creating a twist, many owners learn to live with it.    Leaks can certainly be repaired but unless you do it yourself it can get quite costly, because you may have many small leaks 

Edited September 3, 2023 by Ray Davis

[terboggs]

7 minutes ago, Ray Davis said:

I wouldn't say it's normal but it's common.  They were not designed to leak, however, most coaches do leak to some extent.      And if it's going down evenly, not one corner going down creating a twist, many owners learn to live with it.    Leaks can certainly be repaired but unless you do it yourself it can get quite costly, because you may have many small leaks 

i do have air leveling jacks, not sure how to turn it on auto 2001 Monoco Exec

25 minutes ago, Ivan K said:

Do you have air leveling or jacks or both, do you leave it in Auto, are you on level ground or severely unlevel? You would get better answers if you describe it closer. The generic answer would be that you have minor leaks if it takes a week.

Air leveling, and not sure how to make to on auto, 2001 Monoco exec

[timaz996]

Turn your air leveling off then press the on or air button twice. That is auto leveling.

[vito.a]

Air Suspension Leaks

 A large percentage of the time (maybe 90%+) the leaks are in the air solenoid valves, or "6 packs". They need new o-rings installed both inside the solenoid and also where the airlines insert into the solenoid.

You need to get the coach up in the air because after you locate the leaks you need to bleed the air down to work on the solenoids. If you do not have a lift, build some ramps from 2" X 12" boards stair stepped together.

Someone also posted a link to a leak detector spray product on Amazon that is superior at finding leaks.
https://www.amazon.com/dp/B001B00LOS...v_ov_lig_dp_it

This process takes lots of time and patience and very few shops have either. HWH will work on your system if you are near Iowa or Paul Maddox.

A good way to start would be to search this forum and the Roadmaster section on IRV2 and pre-purchase the o-rings needed. Mike Canter suggests you use Dupont Viton orings. The internal oring is a -019 size, the large one on the bottom is a -028 and the small one on the bottom is a -015.

Then remove the 6-pack valves in both front and rear and rebuild them. Label all wires and air lines. Or if you can each, rebuild them in place one at a time.  It will help to have a special "pin wrench" tool and cannon plug pliers to get the valves apart.

Here are some links to get you started:
Air leak in chassis leveling system

You Tube video:  Air leak in chassis leveling system

Hope this helps.

[NAMVET77]

I have the same problem with my 04 Camelot. While on vacation in San Diego I found a truck repair shop that did work on motor homes and was familiar with the six packs. He found a leak on one of the solenoids and ordered a new one.  Went back and he installed it and it’s working fine. The solenoid was $200 dollars and labor was $400
i need to rebuild all of them and have the O ring specks but I don’t have any info on the pin wrench. I’m imagine there are many sizes out there. Does anyone have a part number or a place where I can buy the correct wrench? Thanks in advance. 
Don

[Ivan K]

There's a number of ways to take it apart if you don't want to wait. I have an adjustable wrench but ring pliers worked just as well. A double nut on the stem would work just fine too and you have the nuts already. It did not need any huge force.

[NAMVET77]

Thanks Ivan. I knew I could probably take it apart with the nuts but I like having the right tools for the job. I’m still in San Diego and won’t be home for a while, but it’s on my list to do before the next trip. 

[NAMVET77]

Ok, it's time to tackle the 6 pack air valves (waiting for Gen parts to come in so I need a new project!!!).  From what I remember, the source for the O rings was Valid (located in Canada).  Talked to them and they said they don't service HWH systems??  Dupont Viton are the O rings of choice but where is a good source to buy them? I have the sizes for all 3 O rings.  Also may need a coil or two if they check bad.  Does anyone know what the resistance reading should be of the coil or is it a voltage check? Any POC's at whatever company will be greatly appreciated.  Thanks.

Don

[Ivan K]

I got ALL my orings and hydraulic seals for the coach from www.theoringstore.com. Some shipments showed up overnight, good service. As far as the coils, veurinks has/had complete valves for like $130. There are 2 orifice sizes so order the correct one if needed. Otherwise plenty of generic solenoids on the net to fit the 1/2" stem. Resistance is somewhere around 10 ohm, dont remember exactly.

[terboggs]

and how do we get it in the air to work on those?

 

[Ivan K]

1 hour ago, terboggs said:

and how do we get it in the air to work on those?

 

If the problem is due to sixpack valve leak or coil, it is unlikely for multiple valves to completely fail at the same time so there are different options depending on which one with air leveling and ride hight.

[NAMVET77]

I had a shop replace an air valve on the rear six pack due to an air leak while I was traveling. It was pricey.  Hopefully they put the correct valve in. How do I determine which one to get if I need one?  I believe there was a green Dot on the inside bottom of the valve. I didn’t see any markings identifying the size??? OBTW, the MH still looses air over night on the left rear. So probably another leak. This is why I am going to rebuild all of them.  I don’t imagine the oring store sells coils if I need a new one.  Someone must sell the coils. Probably whoever sells the air valves. I checked the resistance of the old valve and it was 15 ohms. I want to get this right the first time.  Thanks. 
Don

[Ivan K]

Front and rear orifices are 3/32. Tag "lower" valves are 5/32 for speed. Your resistance reading is correct. I replaced one coil with a universal one from Amazon for cheap but later got a new part from Veurinks for spare.

[Ivan K]

BTW, the orifice size is marked on the valve assembly.

[NAMVET77]

Thanks Ivan. The one that was replaced last summer has a label on it but it’s not readable. But at least I now know which size to get. I’m ordering the orings today and hopefully will be able to start next week. The MH is up on blocks ready to go.  More to follow. 
Don

[amphi_sc]

Just curious if that 125 psi rating is sufficient or if there is some regulator that reduces the air suspension pressure from the main tanks as my system cycles between 110 low psi to 135 psi compressor cutout. Or maybe my Valid system uses differently rated valves.

[Ivan K]

There's no regulator between the sixpack inlet and PPV at the tanks. Given the small orifice size (something like 0.03 square inch), the pressure on plunger closing spring is in hundreds of the inlet pressure (the spring is really soft so that the small solenoid can pull it in) and the airbag side can see the full tank pressure only if you hold the raise button until bags fully extend and eventually the pressures even out. The valid system that I have seen is using the same looking plunger stem but the orifice is machined into the manifold, so the bronze looking part in my picture is eliminated. I kinda prefer the replaceable orifice since manifolds are way more expensive but the chances are none with proper air system maintenance.