No Suspention Dump

[Old Hardware]

The old girl dumps by golly!!, first time since I had her.

In an effort to pass along the fix for no suspension dump I will post the fix, some of my findings in hopes that it may help someone who has been experiencing this problem.

While at the Birds Nest we spoke with Jesse about the suspension dump system. He was not aware of a coach that had a suspension dump on the dash and one on a control panel in front of the right real time.

He explained that there were 5 clippard air control valves in the FC behind the grill in front of the steering column. To access these the grill has to be removed and a plate with approximately 15 Phillips screws removed.

The 5 were used as follows; Two, one for each of the air seat position switch, Two, one for each of the front air vents, and one for the suspension dump.

The suspension dump valve sends an air signal to the pilot valves, one in the front, two in the rear. This pilot valve does two things, it bleeds the air bag down and it blocks air from escaping from the supply tanks. If it did not function doing both the air supply would bleed down each time the suspension was dumped. Air is transferred to these pilot valves through a small, maybe 1/8" black tubing. In another post Randy D said he could not dump his suspension if the air supply was down and this is the reason, the pilot valves need air to operate. Another poster said his air supply was leaking down when he dumped the suspension. I believe the pilot valve is not blocking air coming from the supply in his case as it has to do both.

Meanwhile back at the ranch, ah..er..the Birds Nest.
My good friend and neighbor, Bryan Altier, of over 40 years, about as close as family, more in some situations, had taken off the grill and removed the inspection plate. He immediately spotted a wire missing from one of the front clippard valve (these have a yellow plastic top) and said, "I believe I see your problem", turns out he was right.

We measured the voltage on the back side of the valve, 12 VDC. The front tang/lug had broken off near the coil and the female spade connector was close by. In the vicinity we found 3 other wires not connected to anything just taped back upon themselves with electrical tape. I/we have no idea where these go, possibly to the second dump valve switch at the coach side leveling station. Since one side had voltage and the other broken I encourage Bryan to use a piece of wire grounded on one end touching the exposed broken tang on the other. When he did did this the coach sank immediately...aha!

The coil of this valve is operated by supplying a ground through the dump switch on the dash opening the valve supplying air to the pilot valves near the height control valves. Now how simple is that?

We checked with BB parts, none was in stock..come to find out these little jewels are $60+. Bryan crimped the female connector some with pliers to make a tight fit then slid the connector over the broken tang. Afterwards he used electrical tape to make a secure physical connection by wrapping tape tightly around the coil including the connection area. A few tries dumping, the dash switch worked flawlessly. We never could get the outside dump switch to work, it could possibly have been one or more of those wires loose that we found loose around this coil??

It is a new experience being able to dump the suspension, I never had this before so I didn't miss it, the coach would come down in a day or so, but I do say I like this operation better now.

Thanks to all who chimed it and especially to Bryan Altier.

[Randy Dupree]

great post Bob!
i got some of those clippard valves for Curt Sprenger a few years ago,for the same reason.
good to see you at maxton/rats!

[Bill Pape]

I knew those yellow capped Clippards were for the fresh air vents , But I had no idea or clue what the others controlled.
Thanks Bob for the follow-up.

[fxdwg]

I had the waste dump clippard leak on me. It got moderately bad before I replaced it. I took the old one apart and firmly believe they're rebuildable. It's just a couple of I rings on a couple of sliding brass pucks with a spring. As the pucks move, the air flow through the switch body changes. Very simple, really. I'm not sure they shouldn't be taken apart, cleaned and relubed every couple of years.