Kneeling Bus

[WorkingOnWise]

Has anyone messed with making a GMC coach, especially the pre 1970 fishbowls, kneel on demand? Any success?

Thanks
Keith

[tekebird]

now that is simple and doable

[WorkingOnWise]

LOL!! Thanks!

I imagined that a 3 way valve that will block air from dumping out of the brakes, but allow it to dump from the bags is all it takes. And maybe a tank to speed recovery when I want the coach to stand up again.
I'm hoping someone has done it and has a recipe to whip it together with a minimum of trial and error.

[NJT5047]

Call Luke or Sam Caylor and buy a used kneeling valve off of an MCI. 
They are often removed and tossed. 
Are the front airbags "T'eed" together on a GM?  If not, you'll need two kneeling valves.  They are fed by a large line so recovery is fast. 
As I think about it, Pete "RTS" had something for this purpose too.
Problem solved.   
I use an IR adjustable regulator to control my front ride height.  Allows use for leveling, or just dumping the air...which I have to do in order to get the bus inside the barn.  An adjustable regulator is not a fast recovery system.  It comes up pretty good, but slow to settle.   
JR

[WorkingOnWise]

A kneeling valve from an MCI huh? Cool.
I had to dump the air from the bags last winter (05-06) when I backed hard into a snow bank and couldnt get off. The tires just rolled...and the coach didn't! I shut down the engine and pumped the brake pedal about a bazillion times. Finally, the weight of the bus on the snow crushed it down so I restarted the engine, let the bags fill, and drove away like nothing ever happened. We did make a nice 6V71 show angel!
But, I want the kneel ability only for kneeling, no other reason. Yeah, thats my story, yeah..

[TomC]

Call it kneeling, or call it manually leveling valves.  I made my own system.  For each position (I have one valve in front and two in the rear-I think like yours) you need one normally open solenoid and two normally closed solenoids.  First install the normally open solenoid between the leveling valve and the air bags-this serves to cut off the air supply from the leveling valves when activated.  Then between the solenoid and the air bags T in the two normally closed valves-one for exhaust and the other hooked into the air system of the bus-in this case I tee'd into the air supply to the leveling valves.  The operation is you activate the normally open valve that closes.  Then you can either activate the exhaust or pressure solenoid to make the bus go up or down.  This is not fast, but I can level my bus at the campsite in less than a minute-and usually stays put for 3 or 4 days.  If you want faster, have to get bigger solenoids with bigger pipe bores to pass more air.  Many different solenoids made.  Good Luck, TomC

[WorkingOnWise]

Tom, what valves did you use?

Thanks
Keith

[TomC]

They are continuous duty 12v dc solenoids (I've left them on sometimes for weeks on end).  The make eludes me-it is a popular brand, want to say Shrader, but not right-I know it starts with an S (starting to sound older than my 51 years).  Anyone help out here?  Good Luck, TomC

[Len Silva]

Skinner?

[WorkingOnWise]

Len, I googled "skinner valve" and got the parker website, so skinner is a brand of parker it looks like, and it looks like what TomC means. Is it TomC?

[Sammy]

The RTS bus had a good kneeling cluster on it. Solenoid valves, quick fill valve, all mounted together on a small bracket that bolted to the front bulkhead. FYI. 

[HighTechRedneck]

Larry Ward is selling RTS parts on the e place.  I just bought a couple parts from him.

[TomC]

Yeh- Ah. Skinner, that's the ticket!! Good Luck, TomC