air leak from passenger wheel well

[Artemisprime]

I have a 2000 alpine coach that's new to me and i wanted to get some clarification about this air leak that im having. So anytime i start the RV and as soon as it starts to build air pressure this hose starts leaking air out of it. it will leak until i shut the RV off and then it will continue to leak for a little bit longer and then it stops. i will include a photo and hopefully someone can share if this is normal.

[wolfe10]

That is a ride height valve.

[Cuda67bnl]

And that line looks split in the middle

[kenwyatt]

Correct on ride height valve. Function is to add or release air from the suspension to maintain height/level as you drive. Could be the valve has a internal leak, body is split as mentioned above or the leakage is way out of adjustment. The linkage goes between the valve and the axle. Axle goes up valve releases air from the suspension so the body should stay stable, Axle goes down it adds air to perform the same function. Most coaches have 3. This is to provide front to back and side to side stability. Be careful under the coach as the body can change height in relation to the axle so avoid pinch points but the valve is fairly simple.

[Alpine06]

Hmm, my guess is that your hight setting on this side of the coach is incorrect and the valve is bleeding air off. The circled line is not the air supply.
So this side of your coach is higher and the valve tries to adjust the air bag lower. My experience is that the front axle is so stiff at one airbag will lift the whole thing up. That makes it quite sensitive to adjust the front for correct corner weight. The rear is much easier.

[Bruce Anthon]

I have attached two photos from Neway of the manual for testing the valve and adjusting. The inspection procedure outline will help you verify the proper function of the valve before ultimately setting the ride height. It is also a good idea to the use soapy water spray to check for leaks on your finished work.

The circled hose is the exhaust line for the leveling valve. There is a slight delay as the suspension goes up and down before the valve actually responds. The easiest way to set dual valves (one on each side of an axle) is to unhook the linkage of both valves and move both leveling valve arms so they are pointing down. That will exhaust the air in both bags. Use the engine to bring the service air up to 120# as noted when the air dryer pops off. Then hook up one side and adjust the bag to its proper ride height. I dump it and reattached the linkage a couple of times to verify I have the right ride height. Then dump the bag you just set, go to the other side and go thru the same adjustment steps. Once the second side is set, hook up both linkage arms. Setting the bags this way eliminates one bag fighting the other when the unit is in operation.

Note that the directions explain how to use the bolt on the arm of the valve for adjustment. Do not adjust by changing the length of the linkage rod. Good luck!

[wolfe10]

While you are under there (yes, with safety stands in place), be sure to measure and adjust as needed RIDE HEIGHT. Each wheel position is individually adjusted. Yes, 4 ride height valves is pretty unusual, but that is what your Alpine has.


A good idea to check ride height annually.