2000 U 320.
The front end of the rig will not stay aired up. The rear of the coach will maintain the height. There is a loud air leak coming from under the rig in the front when the rig is running. I installed safety blocks near the airbags but since there is no pressure from the weight of the rig, I can't pinpoint the air leak. My friend thinks the air ride height valve is the issue.
You could have had a piece of road debris fly up and cut a hole in one of your air lines that feed the suspension. More investigation may be needed to find the exact spot so you are not just throwing parts at the problem.
Mike
reece1975,
That ride height valve looks like it is almost new. Was it replaced recently? The only place air should exit that valve is through the exhaust port (rubber cover) on the bottom. If the coach is sitting at correct ride height, the rod connected directly to the valve should be perfectly horizontal. With engine running there should be no exhaust from the valve. In that condition, if the rod is (manually) moved down from horizontal (like in the photo), then air will be exhausted from the bottom port.
If the coach is raised up on safety stands (as it appears to be in your photos) and the engine is running, air will be continually exhausted from the valve as it attempts to lower the coach to ride height.
In other words, you can only verify the correct operation of the ride height valve with the engine running and coach at correct ride height.
The "weight of the rig" won't make any difference in finding air leaks. Putting "weight" on the suspension does not increase the "pressure" in the air system. Air system pressure is what it is.
BUT, how the coach is sitting DOES influence the action of the height control valves. See my comment above.
By the way - looks like you have a NICE coach barn to work in. I am envious! ^.^d
I understand. The air leak sound no longer exists when the coach is on safety blocks. When the rig is running and I spray soapy water on all the fittings, I can't seem to locate a leak.
I purchased a new ride height valve from MOT. I hope this corrects it
You can bench test the old (or the new) valve when it is off the coach. Just rig up a simple air line connection from your shop air compressor to the top fitting on the valve. Put a little pressure (100psi) on the valve and see if it leaks. Move the horizontal rod up and down through full travel and see what the valve does.
If it operates correctly and no leakage from the wrong place, keep it as a spare.
Your air ride system probably has an air dump solenoid valve that very likely could be leaking. On my rig that valve had the exit port facing forward and over time the port filled with road wash dirt some of which got under the valve seat. So -- check that air dump valve, that could be your problem. Have a great day. ---- Fritz
If you don't mind me asking, what did it cost you?
$150 from MOT
This is something I do with electrical motors by attaching directly to the car battery. With the air actuator, I preferred just changing them out, considering their age. If changing out, I highly recommend doing it yourself; it forces you to learn how it works and being able to remember it, as opposed to just reading about it.