4106 Front Air Bag Question

[richard5933]

Our 4106 holds air in the rear seemingly forever. The front, however, is a different story. I parked the bus where it is right now on Sunday, and by late Wednesday the front had dropped about an inch. Today it's down about 1-1/2 inches.

The shop has checked and double checked the air bags for leaks. So far they've found nothing leaking. They've gone over the system rear-to-front a few times, and all they've found is a loose fitting on one of the lines. That was tightened and helped, but it didn't solve the problem.

The front leveling valve has been changed with a new one from Luke. The bus sits perfectly level when running and airs up quickly, even when settled like it is now. I could start it right now and (knock on wood) it would be ready to drive in less than 10 minutes at about 110-115 psi and at full height.

It's obvious that there is a leak somewhere in the front. Probably a pinhole somewhere that is leaking too slowly to be easily caught or that is in a place not easily visible. My thought on how to proceed right now is to order four new front air bags from Luke and have them installed when we get back from our trip next week. It drives fine, but the problem comes with the front dropping when we're camped somewhere. Other than finding and fixing the leak the only alternatives I see are starting and running the engine every few days or hooking up the portable compressor.

Does anyone have other suggestions or advice?

Thanks
Richard

[TomC]

You're worrying about something that is near impossible to fix. My 4 bags in front also deflate after about 4 days-and that's with the leveling valve bypassed with my manual leveling system. If that bothers you, fire up the engine every 2-3 days to raise it back up. Or buy a nice quiet electric compressor (like a California oil less) and run the air compressor every couple of days.
Trying to find the leak-especially unnecessarily replacing the 4 air bags gets expensive. Good Luck, TomC

[chessie4905]

You can nrrow it down by isolating air bags and installing a Schrader valve/s ( like a valve on a tire valve stem ) to one bag or all four. Inflate all or one and check the next day or two. I did this and found one leaking slowly. Of course, I have a pit, so it is simpler. If they all hold air, then install valve before leveling valve after reconnecting air bags.see if it leaks. Get some ac leak checker at a house, commercial  ac dealer supplier or mcmaster-carr or maybe ebay or Amazon. Comes in bottle with small dauber. It will show very small leaks. I would try this first on all your air bag and leveling valve connections before you disconnect anything, incase you get lucky and it is just a seeping fitting.


http://www.nucalgon.com/products/gas-leak-detectors/gas-leak-detector

This is what I use, although my bottle is white with red lettering. There are other brands that do the same thing. I would avoid an aerosol for this job. Too much over spray.