Air leak

[Dale Malquist]

2007 Contessa. I have an air leak that is now causing loss of air overnight.  The leak has gotten progressively worse. I was suspecting an air bag until searching this forum. Is there a procedure to find the source of the leak?

[Mike Shumack]

Hi Dale,
I've been chasing air leaks on my coach too. You just need to get under coach and spray all the air fittings with soapy water.

I used some soapy water in a spray bottle, but found that my home-made solution of dishwash soap and water did not work too well. I ended up buying some specialty spray for leak detection https://www.amazon.com/gp/product/B001B00LOS/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 (but after seeing/buying the "leak detection solution" I think the problem with my home made stuff was that it was too thin).

I found the majority of my leaks where coming from the HWH air leveling system manifolds. I also had some leaks at the "push-to-connect" air fittings at the air tanks. These I replaced with standard truck compression fittings.

Do you lose air in both tanks (red and green)?

[Dave Atherton]

Dale, make a suggestion going down the road it is very possible your motorhome air leveling
arm has wear and not centering because on little out of adjustment. When parked and air
is bleeding off very slow ( look at each side front and back if air leveling valve you will some idea
Which side and front or back). Another area is your air dryer pop off valve not seating and
engine not running.  Dave Atherton Retired Cat Mechanically

[Dale Malquist]

Thanks Mike: I do not have the HWH leveling system in my coach. will get, or make, some leak detector. As to the the tanks; I assume I have two as there are two gauges on the dash. Not sure which is which but both drain down over night.

[Dale Malquist]

Thanks Dave: Going down the road the coach stays level. Where do I find the air leveling arm? Where are the air leveling valves? Will check the air dryer pop off. I have the Valid/Powergear leveling system.

[Mike Shumack]

Your coach may be a little different than mine, but the leveling valves (Ride Height Control, RHC) should be similar. The picture is from my Owners manual.
On my coach there are two RHC valves on the rear axle and one on the front. The valve is mounted to the frame above the axle and the linkage/rod goes down to the axle.

The hard part is getting under the coach to check these. Once your under there (with air pressure built up and engine off) you can check to see if there any air leaking out the exhaust (which is just a 4 inch long tube coming off the valve). Then spray yoru leak detection solution on all the hoses and fittings and look for bubbles.

I made up some ramps out of 2x12 boards sandwiched/screwed together to drive the back wheels onto. That gives me enough clearance to slide under my coach on a creeper.

Also, on the fittings, Beaver uses "Push-To-Connect" fittings, which always seem to leak a little. These fittings are great for assembly line workers but not so great for owners that want to disassemble to repair. I have found about a dozen of these fitting leaking a little air (it adds up). Out of a dozen or so, I have only been able to disassemble two of three. I usually just cut the nylon tubing where the fitting starts and replace the fitting with a Parker air-brake compression fitting. Even if you could disassemble I'm not sure you could get the o-ring to repair a leaking fitting.

[Steve Huber Co-Admin]

Dale,
You'll have fun getting to the air lines as they routed a lot of them up against the floor of the coach. Mike's suggestion of running it up on ramps is a good one as you'll need room to be able to sit up under the coach to get to some of the lines.
Steve