Simple & inexpensive leveling system for early GM coaches with air suspension

[sledhead]

kiss



push to add air pull to remove air ....... no power needed

dave

[thomasinnv]

Gg04 you have that backwards. A 4 valve system is much more likely to twist a coach than a 3 valve system. In a 3 valve system both sides on the front are tied together allowing for side to side movement. There are a few coaches that have one valve for the rear and 2 in front, still considered a 3 point system.

[uncle ned]

Huggy has 4 hydraulic levelers and 4 way air levelers.   Never had any trouble with her twisting.

But ever coach that has 3 way hydraulic levelers seem to sway or wiggle on the end with one down,

by the way huggy has been converted a least 15 years.  not broke into yet.

uncle Ned

[uncle ned]

If 3 way was so great why do they put 4 tires on instead of three.

I think the main reason for 3 way is financial  save the cost of 1 leveler.

uncle Ned

[zimmysurprise]

A three point leveling system does essentially reduce the twisting, but most of the problems with a four point leveling system is how you level it. It's no different than leveling a travel trailer. If you were to crank each corner down one at a time to the desired elevation, it twists the frame. By alternating corners, the "twisting" has no more effect on the unit than driving over a curb.

[Dave5Cs]

Exactly. Think about it the body ( no frame on a MCI at least) is straight and even you guys with leveling valves have a 3 to 10 second delay in your leveling valves doing anything. Thats in the manual. The reason in so that the Bus has time going down the road to level or not if it changes. If the pitch is so great that it needs to adjust without make the passenger uncomfortable with the levelers always moving it will adjust faster. So the point being that your levelers would be more prone to tweak the body than 4 way valves because they are always adjusting. A four way adjusts the axles are moving but not the body so point is moot. It would be moving together and doesn't tweak or bend.
When I raise or lower ours I use two valves until I get close or drop one that needs more but you do it slowly. it take me 4 minutes sometimes to adjust at a really angled campground. No twists no pops and no one left on 3rd!...
Dave5Cs

[eagle19952]

A three point leveling system does essentially reduce the twisting, but most of the problems with a four point leveling system is how you level it. It's no different than leveling a travel trailer. If you were to crank each corner down one at a time to the desired elevation, it twists the frame. By alternating corners, the "twisting" has no more effect on the unit than driving over a curb.

who drives a bus over a curb...?

[Oonrahnjay]

who drives a bus over a curb...? 

     That's sort of related to the guy who drives a Volvo -- he's never been IN an accident but he's seen hundreds!

[Dave5Cs]

Here are the ones I use and mounted on wall thigh high left of driver seat.

[gg04]

This is another topic that has been around a lot longer than these boards . Factory system is just for weight not leveling. Leaving front wheels together will always cause twist. Air will not balance out fast enough as you raise or lower one side or the other.  Don't believe it just run string down the side front to rear btdt..rdw

[thomasinnv]

This is another topic that has been around a lot longer than these boards . Factory system is just for weight not leveling. Leaving front wheels together will always cause twist. Air will not balance out fast enough as you raise or lower one side or the other.  Don't believe it just run string down the side front to rear btdt..rdw

First I have ever heard that. I have had a manual 3 valve system setup on mine for years and never had any twisting problems. As far as the front sides not balancing out fast enough and twisting. ...that's a bunch of hog wash. Personally I think you're talking out of your @$# but it's your bus do it your way.

[Dave5Cs]

LOL and the debate goes on. Shifting weight would be Leveling out when they compensate?
Dave5Cs

[dtcerrato]

Lots of different s books of thought here, cool! That's what the board's all about right?
Appreciate all the conversation. Have a great week end...

[Dave5Cs]

Dan have a happy Easter from the Left coast!...
Dave5Cs

[zimmysurprise]

I found a patent from 1985 for a similar 4 point leveling system.

https://www.google.com/patents/US4641843?dq=motor+coach+patent+1975&hl=en&sa=X&ved=0ahUKEwjXmPWItvPLAhUEkYMKHUEDAxIQ6AEIXDAJ