Air Leveling Questions

[Dick Simonis]

Currently I have a 3 point hydraulic leveling system by RVA.  I've been reading a few threads regarding the advantages of air leveling and wonder if it's possible/practical to add air leveling to my PT.  Intuitively, it would seem rather easy but you know how that goes.

Thanks for any input.

Dick

[John and Judy Gardner]

I discussed this with Elite Mobil Repair out of Eugene, they started their service after being laid off from Monaco. The quote was around $5000.00 and it is quite a task to under take. For that kind of money I did not think it was practical.

[Gerald Farris]

Dick,
I know of several owners that have had air leveling installed on their coaches. Most of them were installed by the HWH factory service center. I believe that the price was in the $4,000 to $5,000 range. So if your hydraulic leveling system is not giving you any trouble, it is probably not worth the cost to you. However if your hydraulic leveling system is causing problems like repeated broken windshields or it needs extensive repairs, you might call HWH and discuss the cost of installation of an air leveling system.

The installation of an air leveling system is more involved than you might think. You will need a new touch pad (operator control), new control module (computer), probably a new level sensor, a new set of air control valves because the air leveling system will control the air bags at each wheel separately unlike the air suspension that controls the fronts together on most coaches, and all of the wiring and air line changes to make it work.

Gerald        

[Dick Simonis]

I am liking the Hydraulic leveling more and more.  4-5K simply isn't worth a small advantage.  Thanks for the reply.

[JimDyer]

Dick, the cheapest way to do it is to find a coach with air suspension when you are buying.

[Butch Martin]

I still like my 3 point Hydraulic

[Jerry Carr]

Hi Butch

I think if you did install this yourself it would be a great project to keep you busy during the off season!

[Richard And Babs Ames]

Go to HWH.com and they have Active Air, which is a system that includes air leveling.  Had to be installed at their factory in Moscow, Iowa. Cost was in the $6000 range.

[Edward Buker]

The up ride with the hydraulic leveling system that goes between the frame and axle is perfectly acceptable in the auto leveling mode on our 2002 Marquis. The down mode is as some put it a Class B Fair Ride. In my mind it is scary at best and inside the coach it feels like an out of control retract of the cylinders.

Before leveling, we manually dump all the air. We also air up before we retract the leveling jacks. In many instances the air suspension valves, on at least one axle, will not pass air to the air springs until the coach has lowered some. The only method I use is to bump the manual retract switch momentarily in small increment allow the coach to drop in small steps until the air gague starts to drop indicating that the leveling valves are allowing the air springs to fill. I pause there until the gague has stopped falling and once the coach is resting on air I hold the manual retract until all the cylinders are fully retracted.

There is no apparent racking, no violent down travel, and most of the cylinder retract occurs once the coach is leveled using the air suspension. In my humble opinion this is the only procedure that makes this type of leveling system acceptable. Other hydraulic systems that go to the ground may be better but this unique Magnum system that uses the axles is a good idea not well executed in my opinion. The rate of fall would indicate that the oil flow rate is too high in reract mode.
If you have this system you may want to try this method and see what you think. If others have a better technique please post it. I know this is has been discussed in the past but some new learning may be out there. Given this methodology I am happy enough to keep the $5-6K for an add on air leveling system in my pocket.

Later Ed

[JimDyer]

Ed, can you give us more info on this system. As I read your post, you have a hydraulic 'air leveling system'. So it has all the disadvantages of air levelling (can't lift the wheels, no footpads for my wife to put her hands under when I'm levelling, etc) but is hydraulic?
What models have this system?  

[Edward Buker]

My coach has air suspension that levels using mechanical valves that meter air to the air springs for over the road travel like most Beaver coaches including yours. This is a fixed system always trying to keep the coach level while going down the highway with air flowing in and out of the air springs as required. The only adjustment is a fixed rod length that is set up to maintain a 10 inch dimension plate to plate from the top of the air spring to the bottom of the air spring on level ground. This sets the ride height.

For a few years, I think 2001 through about 2003 (Gerald probably knows for sure) SMC had a unique system where four hydraulic cylinders were mounted vertically above the axles, one per wheel well. Flat pads were welded on the foot of the cylinders as well as the top of the axles. The cylinders lift the coach using the axles as landing pads rather than the ground. The good points are that you never lift the wheels off the ground which is a safety concern and you never need to use pads on the ground given the rams work within the frame of the coach. It is also a more stable stance given no air springs are involved while sitting and no compressor cycling. I like these features.

Once during leveling on my last coach I got too exuberant and lifted the rear wheels enough where they lost traction and I literally had the coach fall of the hydraulic rams. The parking brake is rears only and it was risky to get the rears too high. Kind of like Russian Roulette leveling...

When the hydraulic system levels the current coach, after you drop air from the air springs, many times it has lifted the coach high enough on at least one of the axles that the suspension air valve is not allowing air to flow back into the air springs and they remain empty. This is the "long drop" at too high a rate if you allow auto retract to release the hydraulic pressure. Had the flow rate been engineered to a much lower flow level I would be very happy with this system. Some folks have had restrictors added and some have had air leveling added to overcome this problem.

The best procedure I have come up with to live with this limitation, is to air up the coach, and tap the manual retract button allowing the coach to drop a bit at a time until the chassis is low enough to allow all the air suspension fixed valves to fill the air springs. I pause at that point using the air guage to tell when to proceed. Once filled and the coach is resting on the air springs then you can fully retract the cylinders at will.

Like most that have it, I would love to have the full auto air leveling option that can be used instead of the hydraulics but not for the added expense. Hope this helps.

Later Ed

[Gerald Farris]

The SMC hydraulic leveling system was used on select 2001 and 2002 models only.

Gerald

[JimDyer]

Thanks, Ed, and Gerald. We have air and hydraulic, and the previous owner told me he had put the 14th windshield in before he had a sitdown with Monaco in 2004 and got them to do a complete rebuild on his hydraulic jacks, including moving the fronts rearward. I am scared of twisting things, plus the air levelling works very well, so I've never used the hydraulic jacks.

I did have one problem with the air ride in that one side stuck up once. I dumped, levelled, and then hit travel a couple of times and it rode flat after that so I haven't looked at it since. Probably should check and see if the ride valves are all corroded....

[Gerald Farris]

Jim,
You must have one of the first Magnum chassis equipped Marquis coaches that Beaver (SMC) built. The early production Magnum chassis that were used on the 98 Marquis had the hydraulic leveling jacks placed on the front of the frame horns not very far behind the front bumper. Having the jacks that far forward caused excessive twist in the coach and resulted in a lot of broken windshield.

After SMC had built enough Marquis coaches with the new Magnum chassis to see that they had a problem with the jack placement because of all of the broken windshields, the front jacks were moved to a location behind the front wheels were they stayed through the 2000 Marquis production run. This did not happen until late in the 1998 production because the first 26 Marquis coaches that were built used left-over Gillig chassis from the 1997 production run.

Beaver moved the jacks at no charge in 1998 and 1999 for any owners who complained about broken windshields. It is hard to understand why the previous owner of your coach took 6 years to realize the problem.

Gerald

[JimDyer]

I have one of the last 98's, and it is on a Magnum chassis. I know it was near the end of the year because Glenn and Betty Perkins' 99 has a build date about 6 weeks later.

The previous owner bought it in 2003 from the second owner and joined BAc right away, but didn't hear about this for several years.

I kind of wish I had a Gillig - nothing wrong with the Magnum but my 90 was a Gillig.