I have read here about owners removing the level adjusters and installing solenoids,so that they can manually level the bus. While I can see the advantages of this when stopped and camping,but how does this effect the coach on the road? Thanks Mike
just have to return them to road settings. the purpose of the level system on a passanger coach is to adjust air pressure to air bags as passangers get on or off and bagage is added or removed: once your coach is finished it is pretty well a fixed weight. If you level with air pressure gauge you just return them to road setting(pressure). Good luck Bob
There are systems that allow both automatic leveling for the road and manual for when parked. I believe that one of our members markets such a system but I don't remember who.
Mine still uses the leveling valves for traveling. When parked there is a switch that isolates the valves so I can level.
Mine are manual and can be used to level bus on uneven ground. Also if the road is rough I let a few pounds out to smooth out the ride some and on a windy day I add a few pounds to help stabilize the bus. Plus with the air bags isolated the bus has not dropped sense I installed the system.
That is issue with mine it won't inflate I'm thinking of going to manual or getting rid of it all together
When I first tackled that part of the project, I disconnected the leveling valves and installed 4 push-pull valves with gauges and used it that way for awhile. All manual. As time went on, I discovered that it was difficult to get the bus 'back to level' when leaving an uneven stopping point (like pulled off the road for a snack break) and going back on the road again.
The pressure in the bags were not all the same and there seemed to be a point when inflating the bag that the pressure would stay the same but the ride height would rise as more air was pumped into the bag. I would go around measuring the fender well to ground height trying to get the thing level. What a PITA.. I was also concerned about the geometry of the front end and also the drive shaft angle (if I didn't get it close enough).
Bottom line: I re-connected the leveling valves and installed a system of solenoids so that I can use the manual valves for leveling in a campground or uneven parking situation and then when ready to hit the road again, I just turn on a switch to activate the solenoids and the auto-levelers take over. I made it so the solenoids are energized when on the road and when camping they are 'off'.
Just my way :)
phil
Most all buses will have two leveling valves at the rear and one on the steering axle so to have a 3 position-triangle if you will-to guarantee that the pressure is evenly spaced. With four valves, you could be off by many pounds of pressure in the front and not know it creating a body twist. I have the fore mentioned 3 position valves. I kept the automatic leveling valves and installed my own solenoid system. It consists of one normally open and two normally closed solenoids. The normally open solenoid is spliced with a T into the air line between the automatic leveling valve and the air bag. Then between the normally open solenoid and the air bag is a T where the add air and exhaust air solenoids can do their work. So to operate it, I have two switches per position. The manual or automatic (on/off switch) and on/off/on switch spring loaded to either add or exhaust air. It works well-have had to only replace one valve in 15 years. Good Luck, TomC
Great topic! I've got the manual system on my 4106. With recently installed air pressure gauges ( the PO did the tape measure method ) what should I be running for air pressure. The coach scales at about 26,000 lbs.
Thanks
TM
You're book should give you the ride height at each corner and tell you where to measure. Set each corner to the correct height and note the pressure on each gauge. mine is 57# on each corner.
It depends on the ride that you want. I run my fronts at 80 and the back at 70. The reason for that is to make sure that my tow bar is flat between the toad and the bus. The PO said that he ran at 90, i thought that was a little high, pressure wise.
If you can go to GMC Busnuts. About three mounts ago a nut posted the unit with the solenoids (best one I have seen) he had diagrams ,parts list, all you will need. As soon as the weather breaks and warms up I'm going to install it in my 4106.
Just to add a note to my previous post. On RTS's, there is a single valve on the back axle and two on the front (the opposite of some buses - mine has independent front suspension) . I used a solenoid to 'separate' or 'join' the two sides of the back axle(four bags) so the system would work as designed for 'on the road' functionality.
If looking for solenoids - try to get 'no bubble' versions. They leak less ! ;D
phil
Quote from: Lin on February 08, 2011, 03:12:39 PM
There are systems that allow both automatic leveling for the road and manual for when parked. I believe that one of our members markets such a system but I don't remember who.
Yes one of our members did market such a system; I have one. The last time I talked with him, he said he had quit making/marketing them. Something about his wife and him having discovered cruising. If I am speaking out of turn, I'm sure he will post a correction.
I removed the automatic leveling valves installed from the factory. I believe the only reason to have this auto system would be for when you have different loading situations you would have when the bus was in service. As a coach/motorhome the weight or loading should be the same most of the time. That is why I believe I do not need the auto system. With that said I did purchase the leveling system from our former member and have had no problems at all except it is a little slow to level. I would not change the three point system. The front bags control the front to back leveling and the rear bags control side to side leveling. I am glade not to have all the head aches of having those auto leveling valve leaking all the time and running my air down. I leveled my bus last fall and still have the same pressure in the bags as I did then.
John
Lee,
If we're talking about the same guy down in FL, I just got an email back from him and he doesn't offer the kit anymore.
Glad this subject came up, i've been hoping to do some sort of leveling system as well. Anyone out there know of another kit that has everything you need to do this and still maintain the stock auto leveling system?
Brandon
PS-- Jriddle, we were typing at the same time, have you had any issues with not having the stock configuration?
ON my 04 I have a system made years ago by a man by the name of Red Ridout I think.
It has a on off switch that switches from road to park. It also has 4 guages that read the pressure in each bag.
If all fails I use the hydraulic feet on each corner. Use big block if the spot is very sloped.
I do not understand why 3 point is better than 4 point leveling systems. The bus uses all four to level under normal
use. level is level to the bus either way it gets there.
uncle ned
Quote from: brando4905 on February 12, 2011, 11:33:34 AM
PS-- Jriddle, we were typing at the same time, have you had any issues with not having the stock configuration?
Brandon
I have had no issues as you discribe.
John
Quote from: uncle ned on February 12, 2011, 12:43:08 PM
I do not understand why 3 point is better than 4 point leveling systems. The bus uses all four to level under normal
use. level is level to the bus either way it gets there.
uncle ned
My MCI came from the factory with the 3 point system the front air bags receive the same amount of air where the back each side could receive different amounts.
John
Red Rideout is a neighbor. Is not doing leveling systems any more. His coach is sitting. a fine gentleman! Bob
Mechanical level system. I just put a door hinge(barn) and attached bottom of leveling valve rod to it instead of frame. I use a morris cable to move the end of the hinge and change it's anchor point. A pair of levers in the last bay lets you level side to side and back to front. When ready to go down road just return them to the neutral position. Kiss system Bob
Ned,
The three point system is to prevent twisting the body as has already been posted. There are only three leveling valves - the front valve is for up and down - the two rear are for side to side and also up and down.
The original bag system is not designed to level the bus, it is only designed to keep all four axle to body distances the same regardless of load to keep the bus stable while moving.
The name "leveling valve" causes no end of confusion about this!!
Truck cabs were make with three point mounts years ago for the same reason, don't know if they still are. All my trucks are ancient!
Bob,
You mentioned that system before. It sounds interesting. Do you have any pictures yet? Is that what you are going to use on your new bus?
Bob,
Your system sounds like the simplest so far, I'd love some photos as well when you get a chance.
Brandon
http://www.truckspring.com/products/Firestone-Air-Adjustable-Leveling-Control-Panel---Quad-Pneumatic---Black__FIR2333.aspx (http://www.truckspring.com/products/Firestone-Air-Adjustable-Leveling-Control-Panel---Quad-Pneumatic---Black__FIR2333.aspx)
remove all the HEIGHT CONTROL VALVES - (no OTR auto leveling)
<> use as is for 4 POINT CONTROL (not recommended)
or
<> use as 3 point (preferred) with one of the four pressure needles as SUSPENSION tank pressure & remove one pnematic switch
or keep the OTR Height Control by using MAC 35A-AAA-DDBA-1BA (12volt DC / 5.4watts - 18" flying leads solenoids)
to activate the Height Control valves when drivong OTR
Drawing look like the ones I got when I purchased my system from that former member????????????????
My observation
John
Quote from: Jriddle on February 13, 2011, 01:34:45 PM
Drawing look like the ones I got when I purchased my system from that former member????????????????
My observation
John
That "Before and after" drawing IS one of the drawings that he did use. Shouldn't be too hard of a system to build now that norules has posted the Mac Valve numbers. Those can be purchaced from most any Industrial Supply house.
Norules,
Is that the right part number? It looks like the DDBA is 12 volt.
Manual leveling system; parts 2 barn door springs 8 inch free end two Morris control cables 1 each approx 5 ft long and 1 each approx ten ft long. a two lever control unit (mine home made). UN do bottom of level rod where attached to frame. weld or bolt barn spring with long side free under control rod. attach control rod so it can swivel to free end of spring. attach one end of Morris cable to free end also. Movement of the cable will move the free end of the barn spring and therefore move the anchor end of the leveling valve rod. so you are changing the location of the anchor end or the leveling valve and it will correspond with more air to return to neutral position or exhaust air again to return to neutral position..... Basic you are just changing the anchor location. will try to get a pic of mine..Yes I'm using on new coach also. Simple no elect solenoids just a mechanical change in location of anchor location. just return lever to stock setting(notch in lever) to go down road.
Quote from: Lin on February 13, 2011, 01:54:01 PM
Norules,
Is that the right part number? It looks like the DDBA is 12 volt.
You are correct in that was a 12V valve number... Good Catch.. The part # for the 24VDC 5.4 watt MAC Valve is 35A - AAA - DDAA - 1BA
They are on Ebay for $19.95 each..
http://cgi.ebay.com/MAC-35A-AAA-DDAA-1BA-24V-DC-Pneumatic-Solenoid-Valve-/190495856064?pt=Pneumatic_Hydraulic_Valves_Parts&hash=item2c5a7015c0 (http://cgi.ebay.com/MAC-35A-AAA-DDAA-1BA-24V-DC-Pneumatic-Solenoid-Valve-/190495856064?pt=Pneumatic_Hydraulic_Valves_Parts&hash=item2c5a7015c0)
Very good catch
MAC-35A - AAA - DBAA - 1BA is the much harder to find 12 volt DC solenoid
MAC-35A - AAA - DDAA - 1BA is the VERY COMMON 24 volt DC solenoid
what's inportant is to use a (BI-DIRECTIONAL SOLENOID)
Because
most solenoids and standard SKINNER valves - WILL HOLD PRESSURE ONLY IN ONE DIRECTION
and not to worry - I had the former Members permission to use and modify the (before & After) picture
Hate to reply to my own post.I do recall someone on this sight replacing the leveling valve arm with a actuator,(3 position I assume).when the actuator was returned to the neutral position,the bus would revert back to auto. Does this seem workable? thanks ,, mike
Quote from: mikke60 on February 13, 2011, 05:19:55 PM
Hate to reply to my own post.I do recall someone on this sight replacing the leveling valve arm with a actuator,(3 position I assume).when the actuator was returned to the neutral position,the bus would revert back to auto. Does this seem workable? thanks ,, mike
Sean did that on his bus.
linear actuator. Basicly does same as my barn door system only it is electric. It lies to the leveling valve so it reacts to do it's normal function. I used what I was comfortable with. Sean is comfortable with electric control. Same result we both use stock leveling valve to do job. The coach I am doing now has a 5 valve leveling system from factory. Part of it is missing. I will prob go back to kiss system. Or even maybe try the linear actuator system. The factory system looks like it could have allot go wrong with it. Bob
I used something like this http://www.airbagit.com/product-p/air-con-35c.htm (http://www.airbagit.com/product-p/air-con-35c.htm)
works great. 4 zones... LR, RR, FRT, & TAG
Ok, I see the photo using the 24v valves, but how does one go about releasing air from the air bags before you start to do the leveling. I have seen some S&S motor homes release all their air and settle down and then start to level refilling the bags as needed to level.
Quote from: scanzel on February 15, 2011, 03:49:55 AM
Ok, I see the photo using the 24v valves, but how does one go about releasing air from the air bags before you start to do the leveling. I have seen some S&S motor homes release all their air and settle down and then start to level refilling the bags as needed to level.
I've never seen a working leveling system in a bus but from some of the pictures I have seen, it looks like there are brass mufflers on the air valve switches at the guages. That leads me to believe the air releases at the air valve switch but I also would like to know for sure.
norules where would find the valves and solenoids? having trouble finding them tony
http://www.macvalves.com/distributors/usa.htm (http://www.macvalves.com/distributors/usa.htm)
or
search EBAY with --> 35A-AAA-DDAA-1 (note the last 2 digits is only the electrical connector type - BA= flying leads)