An Air Leak Question

I like that idea Greg, I too was thinking the compressor might be leaking.

JIM

A1: When I owned a Liberty I had to tighten the fittings coming out of the compressor once a year. Even had to replace the fitting once. The leak would become quite severe at times. This is done thru the access panel forward of the front axle.

There is a regulator towards the rear of the coach from the house batteries and forward of the battery equalizers. Damn near impossible to see and almost that bad to get too. You can see it or feel it by going in with your hand from the rear over the chassis batteries. Never did know what it regulated but the line in would leak.

I have a brand new replacement for it if you need it

Thanks Roger, I think I just found my leak.

JIM

Jon:

I have been chasing aux air leaks now for 6 months. A couple of things that I have found which may or may not apply:

I found aux air fittings in places I would not have expected (e.g. plumbing bay). It looks like a couple of splices put in by a previous owner. Yep, one was leaking.

Also. I have found that some leaks change based on last use. for example: drive all day, only use air slide, aux air leaks down to 40 in about 4 hours after docking. Last trip, drive all day, cycle all house aux air systems at docking, aux air holding 60 in 24 hours. Narrowed this down to bed lift. So, drive all day, dock, cycle bed lift, aux air holds 60 in 24 hours.

I know that's not a fix, but I feel like it was a valid observation and has proven helpful. I am no longer threatening to shoot aux comp or aquairium pump as I refer to it.

Also, I found if I raised the preasure in a circuit about 10 lbs, it made leaks a little easier to find.

I'm with Jim K. The belt tensioner valve stumped me for a while. What I found was that the since the hole at the bottom of the valve is so large, it wouldn't soap up. Actually, Jim Shoen found this for me. I had soaped up all the usual suspects but couldn't find any bubbles. But when Jim put his finger over the hole, he felt pressure build up. I NEVER would have figured that one out. Maybe not your problem Jon, but for others, this was a tricky place to find a leak.

Good luck.

Adam

Adam I had that leak. I put in a new valve and it leaked the same. It was the tension cylinder that was bad that ended up being the culprit. In a pinch you can stop that leak and still maintain belt tension by turning that valve slightly till the leak stops.

The flange for the diaphragm for the regulator for that is also a good place to look for bubbles.

As soon as I can get under the bus I will get back at the leak chasing.

I aired up the system to 130 PSI hoping I would create some noise at the leak.

I am seriously considering the use of freon and a sniffer that someone previously suggested. With any luck if I can rig up the required fitting at least I should be able to get in the area of the leak(s).

Now I know why Roger traded.

BTW Roger......the first place I looked was behind the compressor cover plate because I remembered you had problems there.

A few more to check:

The air sewer dump valves. There are also connections up above the holding tank on mine where airlines are joined.

The aux compressor head, not just the lines.

I just surrendered and the aux pump runs about twice in a 24 hr period when the bus is not in use.

Except for dumping we don't even need aux air because we don't close the pocket doors or do anything else that needs air. It is just the idea that I have a leak(s) and want to find it.

If my bus ever gets wet it is going to look like a bubble machine with all the dried soap everywhere. At least it smells nice.

Hi Jon,
It would be hard for you to put more soapy water on your fittings than I have.
Yesterday I isolated the two small bellows that tension the belts on the engine and filled them with R-22. Waited an hour and check them with the sniffer. No leak found yet.
Are R-22 molecules any larger than air molecules?
Jim