Leveling Question

[Cary and Don]

I know some of you have used motors on the leveling arms to adjust the air in your bags for leveling.  I was wondering if anyone could tell us what type of motor you used, and hopefully have a picture of the installation.

Don and Cary
GMC 4107
Neoplan AN 340

[Sean]

I used Electrak-1 linear actuators, which I bought on eBay.  I basically searched on "linear actuator" every day for a couple months until units suitable for the application came up.

The actuators in their centered position were longer than the factory adjustment rod, so we had to modify the mount on the A-arms as well as the levers on the valves.



-Sean
http://OurOdyssey.BlogSpot.com

[bevans6]

Sean, how much stroke did you feel was required on the actuators?  I looked on your site for a page that described your system buy couldn't find one - if you have done a description I'd appreciate the link!

Brian

Brian

[rv_safetyman]

What size actuator would I need for my Eagle

Out of curiosity, do you put leveling valves on each wheel, or go with the one valve per axle?  If you go with one per wheel, it would seem to me to get a bit complicated when returning the bus to traveling configuration unless you had some sort of sophisticated control system.

Jim

[Sean]

Sean, how much stroke did you feel was required on the actuators?  I looked on your site for a page that described your system buy couldn't find one - if you have done a description I'd appreciate the link!

Our actuators have 6" of travel and they are normally set dead center.

Sorry, I never got around to making a page on them, but have described them here on the boards in the past:
http://www.busconversions.com/bbs/index.php?topic=7632.msg74845#msg74845
http://www.busconversions.com/bbs/index.php?topic=7632.msg74868#msg74868
http://www.busnut.com/bbs/messages/233/5646.html
http://www.busnut.com/bbs/messages/233/6595.html

Out of curiosity, do you put leveling valves on each wheel, or go with the one valve per axle?  If you go with one per wheel, it would seem to me to get a bit complicated when returning the bus to traveling configuration unless you had some sort of sophisticated control system.

I put one actuator on each existing factory ride height valve.  That's a three-point system (four-point systems can induce chassis twist that will break things; don't ask how I know), one on each side in the front, and a single valve in the rear on my Neoplan (MCI and Prevost are the other way around).

I bought actuators with position-reporting potentiometers in them, then built a simple electronic circuit to be able to return the valves to factory ride-height position.  Three switches, six LEDs, a pair of quad voltage comparators, and six trimmer pots.  Less than $20.

-Sean
http://OurOdyssey.BlogSpot.com

[Busted Knuckle]

I put one actuator on each existing factory ride height valve.  That's a three-point system (four-point systems can induce chassis twist that will break things; don't ask how I know), one on each side in the front, and a single valve in the rear on my Neoplan (MCI and Prevost are the other way around).
-Sean
http://OurOdyssey.BlogSpot.com

Sean our Setra's are the same as yours I guess those others weren't smart enough to copy the Germans (opps did I just type that out loud? )

What size actuator would I need for my Eagle

Out of curiosity, do you put leveling valves on each wheel, or go with the one valve per axle?  If you go with one per wheel, it would seem to me to get a bit complicated when returning the bus to traveling configuration unless you had some sort of sophisticated control system.

Jim

Jim bring it on over to our shop, we'll take care of it for you, and cheaper than a new engine I might add!
  BK 

[rv_safetyman]

BK:  Cheaper than a transmission?

Aren't these buses inexpensive to operate?

Jim

[Dreamscape]

Jim, Spray 'em down with some oil and add a little red dust to them they should be just fine!

Paul

[Busted Knuckle]

BK:  Cheaper than a transmission?
Aren't these buses inexpensive to operate?
Jim

Yes they are Jim, and by the way I have one with an engine down too ('85 MCI 96A3 w/6V92TA)! But it is paid for and not as big a headache as the '05 Setra with the bad trans, and a $5,000 a month payment!     BK 

[uncle ned]

"HUGGY" has a four point leveling system. uses the four air bags to level first. Then has four hydraulic jacks on each corner.

Been this way for years has never broke yet. I can pick up one wheel to change a tire.
but when it is level i can't see where a 3 point system is any better.

looks like you have a better chance of twisting the bus with it

And with the four jacks down it is steady as can be.

uncle ned

[Tim Strommen]

...Been this way for years has never broke yet. I can pick up one wheel to change a tire.  But when it is level I can't see where a 3 point system is any better.  Looks like you have a better chance of twisting the bus with it.  And with the four jacks down it is steady as can be...

The triangle is the most stable base you can have.  If you have a square and three points are higher than the fourth all of the weight is on theose three points until you push down on the fourth.  With a three-point leveling system, the two wheels on one axle shift to distribute the load for the given pressure provided to the axle (essentially the axle self-levels).  The independent bags on the one axle give you the side-to-side leveling, the single point on the one axle gives you the front to back leveling.

On a 4-point system, you need to ensure that the front and back axles are level side-to-side while you also adjust the front-to-back leveling (this isn't really easy to do unless it's automatic...).


The nice thing about the way Sean did his, is that you can set an upper and lower limit in software (which reads the potentiometer in the actuator), and merge that with an inclinometer attached to the chassis - and let the bus level itself.

I've replaced my auto-ride-height air-valves with 3-way solenoid valves (1/16", 1/8", and 1/4").  This lets me totally digitize the height control.  For height sensing, I have a few hall-effect absolute encoders that use the same old arm method fro sensing the height of the chassis above the axle.  That info gets fed into a microprocessor which uses a PID algorithm to adjust the height using the valves (which will either inflate or exhaust air from the bags using 1/16" through 7/16" by using combinations of the three sizes).  When I go into "in-station" mode, it will auto-level the bus using 4 ultrasonic height detectors at each corner (this keeps the bus from bottoming out if the ground is not even), and two accelerometers coded as inclinometers.  If I hit the ignition switch "on", the bus automatically switches back to "road-height" mode and sets the air bags to the correct height. Because I don't have the leveling valves that are constantly reading the chassis height it doesn't settle if people move around inside...

-T

[Jeremy]

Caravans (Travel Trailers) here are leveled by four legs operated by electric screw jacks (not enough weight to need hydraulics). Self leveling is very simply achieved by means of mercury switches mounted longitudinally for fore-and-aft leveling, and transversely for side-to-side leveling. Power is fed to the jack motors until the mercury switches become horizontal and the electrical circuit is broken.

Jeremy

[robertglines1]

another non electrical way....I changed the fixed end of the leveling rod to be movable....used a barn door spring (hindge type) with the bottom of rod attached to one side and the oppisite secured to bus.attached a morris cable  to the movable end and ran the cable to a lever(one for each side)to the utility bay Just adjust to desired height. Over road return to travel position..slot in slide.front is single lever located left hand side drivers seat..food for thought..good luck!

[Ed Hackenbruch]

Well Tim, sounds to me like there are a lot of little things that could go wrong with your system.   l like simple, maybe because i am simple.   I have a 4 point system put in by the PO. The ride control levelers are disconnected, (one less thing to go wrong) I have 4 valves with gauges so i can set each corner for whatever pressure/height that i want.  When leveling i bring each corner up or down a little at a time so that i will not have any part of the bus way out of level with the rest. I think that if i was very unlevel and just ran one corner all of the way up or down then i might run the risk of twisting the bus, but if i am in a spot that is going to require more than a couple of inches of adjustment, i run the bus up on a few blocks so it is closer to level to start with.

[RTS/Daytona]

here's my simple - direct pneumatic campsite leveling systems -

$399 (uses Electrical Solenoid to retains OEN Height Control while traveling)   
or
$299 (does away with OEM Height Control valves + no electrical devices at all) 

http://good-times.webshots.com/album/559324954HVWVXC

Pete RTS/Daytona