Air bag tubing size

[sparkplug188]

Bruce- That jack uses air pressure to run the hydraulic pump on the jack.  Oil does not get inside the air tubing.

This Youtube video shows the air operated hydraulic pump.  The jack shown is a lot smaller than the long ram I posted earlier.
https://www.youtube.com/watch?v=J44ib1npZdM#t=267

[MightyThor]

The problem with this set up is that to let the jack back down you have to turn the threaded valve at the base of the jack.  Not sure how you would do that without squashing yourself.  Also would have to lower one corner at a time.  The air valve only allows you to go up, not down.

Has anybody thought of using these:

8 Ton Long Ram Air/Hydraulic Jack
http://www.harborfreight.com/8-ton-long-ram-air-hydraulic-jack-94562.html

16,000lbs capacity
air operated, manual backup
17.5" stroke
35.7lbs

It would need a large retracting spring, like this:

National Hardware 7688 Garage Door Extension Spring with Safety Cable
http://www.amazon.com/National-Hardware-Extension-25-Inch-110-Pound/dp/B000B4N0SO/ref=sr_1_1?ie=UTF8&qid=1415974854&sr=8-1&keywords=garage+door+spring

Both mounting points on the jack are pivots, so they can't be mounted like "normal" RV leveling jacks (straight up and down, without bracing).  They need to mount similar to backhoe outriggers- see the first picture below.  On a bus, I would mount the ram nearly vertical and mount the outrigger pivot near the differential- see second picture below.





I do not know how the professional leveling systems deal with hydraulic "bleed down".  There must be some sort of locking system that I am not seeing.  I am not sure how to lock outriggers in place.  There is probably a simple way to do it that I am not thinking of.

It wouldn't be a fully automatic leveling system, but it would be an effortless way to level a bus without spending $4000+ on a leveling system.

[sparkplug188]

Thor- You're right.  That setup is only slightly better than carrying jacks and jack stands for leveling.  The threaded valve at the base of the jack could be reached with a long jack handle.  Also, an air valve would need to be mounted on the skin next to each wheel for lowering each jack.  I am really thinking an air leveling system is the better way to go.  The air bags cost about the same to install (on an Eagle), but can easily be hooked up to an automatic leveling/dump valve. "Bleed down" won't be as much of a problem with automatic valves.   It won't be as rock solid stable as hydraulics, but I can live with it.  For long term parking on air bags, I could just air up the bags and put jack stands under each corner to stop the rocking.

[MightyThor]

To make sure the coach doesn't rock I just tell my wife to walk more evenly when she gets up in the middle of the night.  Works for me.

[Oonrahnjay]

To make sure the coach doesn't rock I just tell my wife to walk more evenly when she gets up in the middle of the night.  Works for me.   

     Yeah, that works.  I did that once - was out of intensive care in just a few days.  Something about the words "do you have to walk so heavily ..?" seemed to cause a problem!

[rusty]

The valve to hold the cylinder in place is called a lock valve. They are mounted close to the cylinder. It locks both sides of the cylinder. It unlocks when the pressure is greater than the lock pressure. It is a common valve on stabilizers on cranes. I have them on our 05 leveling system and they work well. One problem I have two cylinders mounted in the engine compartment. When they are all the way up and cool and you drive and warm up the cylinder the pressure gets higher than the pump pressure so the lock valve will not unlock. Solution leave the cylinder extended slightly so the pressure will not build.

Wayne

[lostagain]

A few 2Xs of lumber to drive on to level the bus works good, low tech, quick and easy...

JC


Sent from my iPhone using Tapatalk

[sparkplug188]

JC- No doubt 2x lumber will get the job done.  However, there is so something to be said about the convenience of pulling into a camping spot and automatically leveling in just a few seconds.  My previous RVs took 30 to 45 minutes to set up camp, with the longest and most physical part being leveling.  It took anywhere from two to five tries of adjusting the thickness of the blocks to get level. It wasn't practical to level the RV with blocks for overnight parking.

I think it is worth $500 and several days of fabrication to have some sort of quick(er) leveling system.

[Dave5Cs]

Yep airbags with block off plates. at four corners

I use a 1/2 x 4' piece of pipe to let down my Air overs when I need to let air out of a jack when working on the Bus. I used a dead blow hammer and just gave it a whack to egg shape the end. It fits right over the air release screw.

[gus]

Very true, with the original 3-pt system the bus is indeed twisted when parked on uneven ground.



Jacks - The problem with jacks is they punch holes in stuff and get stuck! No comparison to an air bag leveling system

[solodon]

I just replaced the two rear leveling valves and planned to replace the front ones when I get new bags and plate the front.  I'm now thinking of adding a leveling system and can't figure out how people have retained the OTR system and integrated the leveling system for the 4 corners.  Everything I can come u with has one defeating the other at some point.

[sparkplug188]

Clifford- Any luck finding the schematic for the Eagle factory installed air bags?  I sent an email to your gmail account, but have not received a reply yet.

If anybody has Eagle manuals on CD that you don't need anymore, please let me know.  I am interested in bartering for or buying manuals for the model 1, 10, and 15 just for reference.

Don- Haldex makes a COLAS hand control valve that automatically overrides the height control valve when the parking brakes are set.
http://www.haldex.com/en/North-America/Applications-Products/Brake--Suspension-Systems/Product-Catalog/Suspension-Controls/Valves/Hand-Control-Valves/Colas-Hand-Valve/90555270

HWH makes several air leveling systems that work with the existing height control valves and air bags.  However, I have found it very difficult to find pricing and information on the HWH air leveling retrofit systems.

[luvrbus]

I won't be back home till the end of the week then I can send those to you

[sparkplug188]

Clifford- No problem, Thanks again 

[gus]

I just replaced the two rear leveling valves and planned to replace the front ones when I get new bags and plate the front.  I'm now thinking of adding a leveling system and can't figure out how people have retained the OTR system and integrated the leveling system for the 4 corners.  Everything I can come u with has one defeating the other at some point.

Somewhere is a complete description of a manual leveling system, must have been sometime this year, and it was a good one.

I once thought about adding a fourth valve to the front and running rods from each valve up through the floor.

Crude, but I think it would work. A pain to adjust though from 4 points so far apart.

The secret to leveling the bus when parked is to let as much air out as possible from the high end and then adding to the other end as necessary. This helps eliminate the rocking boat effect.