Air Suspension Blues

[SteveOlsson]

I'm a new member, currently on the road in Half Moon Bay CA for the first time with a recently purchased 1987 310. This used to be the traveling Beat Museum, and is brightly striped with Kerouac.com. Love the bus and have visions of an extended road trip. Biggest concern is that he rear suspension bags are flat. so we are low to the ground and dragging on driveways, etc. too easily. Can anyone point me to a discussion of troubleshooting and hopefully repairing this airbag system? As there are several components involved, part of me is saying this is too complex for a non-professional. Any assistance most appreciated. Steve Olsson

[bkahler]

Hi Steve,

Welcome to Airforums!

Here's the latest repair thread on the rear air bags and tag axle.

You definitely don't want to be driving without air in the rear suspension. Bad things can happen.

Brad

[Smartstream]

Welcome tp the forum. That thread may be more than you want. I would suggest you start with your air compressor. Check the fuse and power source and make sure it is operating. Once you have air the system is pretty simple.

There should be a Schrader valve on the tank under the coach in the rear. You can fill the system with an air hose like you would fill a tire. Once you have air the bags should fill then you can start to look for leaks or other problems.

[92landyacht]

As bkahler stated, I would start by making sure you have compressed air. Do you hear the compressor when you turn the key on? If not, than you need to find out why the compressor isn't turning on. If yes, you'll need to see if the compressor is creating pressure. I installed an external pressure gauge at the compressor outlet to make sure I know what the output pressure is since the only gauge that was installed by AS was for bag pressure. If you have pressure but still no lift than most likely it's related to the lift valve that regulates how much pressure is added to the bags. Usually it's a broken linkage but the valves can fail as well. If you hear hissing, than start there as you have a leak.


Hope this helps. Keep us informed on your progress.

[SteveOlsson]

Hi Bkhaler, thanks for the good info. I had a guy look at it and he pointed out that our process was all good except that we used the lifters to raise the bus, which is not the way to text weight on the chassis... So, we brought the bus down to earth, and saw that the tank was holding air, the compressor worked well enough to expose 3-4 inches of the shiny metal shaft inside the air bags... Since we are now enjoying an entirely different ride experience, I'm assuming that 3-4 inches "lift" is about right. The 345 has a whole different feel now. It glides over the little bumps. I'm impressed with the technology! many thanks.

[bkahler]

I appreciate the kind words but it was actually Smartstream (Dan) that posted the great advice!

When we first bought our 310 the seller had filled the air tank with air but neglected to tell us that the air compressor was not functional. We found out the hard way once we set off for home that the air in the tank will last only so long before the cut-off leaf springs start banging on the bottom of the frame. For that trip the only thing we could do was to stop every so often and refill the air tank.

Good luck on your repairs!

Brad