94WB Leveling Valve/Dump Valve

[Kiwi3]

I noticed that I have a constant hiss from my right drive axle and crawling around it sounds like (I haven't seen it yet) it may be either the leveling valve or the dump valve.

I can air the coach up and she looks level. I just have the hiss, I guess the compressor is keeping up with the leak.

This will be my first rodeo with the suspension. While I've looked at the pinned post on replacing the leveling valve, I missed the class on it at WOG. Are there any secrets to installing them that I should know about, or could I come visit someone while they talk me through it, or is this a find a service center thing?

I'm really not sure if it is the leveling valve, the dump valve, a loose fitting, etc.. Also if I'm under there should I change the panhard bushings at the same time?

[irmagoo]

bruce there is a pressure protection valve up on cross member by drive axle I and others have had to replace the valve/or the the innards it them. there is a vent hole in them spray soapy water up there if that's it you will see bumbles
mike

[Gregg]

Bruce,
I had the same air leak and it was where Mike indicated. All I had to do was tighten the screws on the regulator. Gregg

[Kiwi3]

Fantastic! I'm heading out to check the valve now. With luck it is just that and I can rebuild it.

[Kiwi3]

Yup it is the Pressure Protection Valve. Venting directly from the center of the valve top hat. Problem I have is space to get my body up to it between the axle and the crossmember. I can just barely touch the top of the valve. Is there a trick to getting in there? I'm guessing from where the air is blowing out that the diaphragm is done.

Mine looks like the below:

[irmagoo]

yes its tight I bought new valve and put innards in existing one ... had hwh jacks lift coach high as possible and installed jack stands in place but its a hard job for 2xl guy
,,,, but possible as always be safe make sure coach cant lower and get you I installed my jack stands and lowered hwh until coach made contact to jack stands to make sure jack stands would hold then went to work
mike

[Kiwi3]

I think I'll take advantage of my veteran status and visit the auto workshop on post. They have some seriously heavy equipment, but nothing to lift a bus. But better than me just cribbing the bus on a sloped driveway. Plus I might find a little skinny guy there. LOL

[Dieselbird01]

Originally Posted by Kiwi3

Yup it is the Pressure Protection Valve. Venting directly from the center of the valve top hat. Problem I have is space to get my body up to it between the axle and the crossmember. I can just barely touch the top of the valve. Is there a trick to getting in there? I'm guessing from where the air is blowing out that the diaphragm is done.

Hi Bruce,

Randy and his helper Glen changed the guts on the PPV, in that location, on my coach several years ago by having the coach over a pit.

It started leaking again a couple of years later and I was able to reach it well enough (without a pit) to tighten the four screws enough to stop the leak.

It started leaking again last year so I put the coach on ramps and removed the whole assembly that the PPV is in and installed a new PPV along with pretty much every other part that makes up that assembly.

The only way I was able to get up in there to R & R the assembly was by removing the Air Dryer (I went ahead and rebuilt the Air Dryer while it was out).

With the Air Dryer out of the way it wasn't hard to reach the PPV.

There are no pipe unions (if yours is like mine) so the whole assembly needs to be taken apart if you decide to replace the PPV rather than just rebuild it. Removing the assembly, replacing the PPV and all the associated fittings, check valves, etc, was pretty time consuming and getting all the disconnected lines threaded back on without crossthreading them was a bit of a challenge.

[Kiwi3]

Wow! With new parts is sure is pretty. Mine is, well caked with oil and grime. Thinking I need to do some steam cleaning under here someday.