wa8yxm wrote:
JRscooby wrote:
Lose several inches of ground clearance from load? Don't they use leveling valves on MH? I don't know RVs, but on trucks and trailers load it, rig goes down, opens valve to increase pressure to raise it back up. (My last tractor, 62 lbs of air was 34,000 on the tandem. 95 lbs, was 45,000)
You can only put so much pressure in the bags and then BOOM you flat.
The air bag works kind of like a spring in that if you put pressure on a sprint... it bends and lets you down.. Same with the air bag only there is a more complex relationship between pressure of the "load" and air pressure ... But if you exceed the maximum air pressure (The real maximum not the rated one) BOOM. the bag blows and you are flat.
So yes. you can lose several inches. Now there are other ways to do it where you'd need like 100 tons of cargo to compress. but that's goiong to give you a very rough ride and loss of control so I won't even speculate as to those methods other than say "Eliminate springs and air bags entirely" (I've worked on farm wagons like that)
But air bags are kind of like springs in that the more load you put on 'em the more they "let you down" only difference is the math is a lot harder.
For example if 100 pounds compresses a spring 1" then 200 pounds likely would compress it 2
But with an air bag if 100 pounds compressed 1" I'd expect 200 only to get to about 1 1/2.
, I have owned, driven, and maintained air suspension on tractors and trailers for millions of miles. I don't know what bags are on the OP's MH. They might be more like the puny thing that Dad put on his pickup because he overloaded it. But I assume that if they are factory installed as the suspension, they are designed to carry well over axle rating at a pressure well below the max pressure the vehicle air system is designed.
Reading what you post, I'm not sure you understand how a air-ride with a leveling valve works. MT truck, the gauge will show a low pressure, the distance frame/axle is the distance the valve is set to maintain. Add weight, frame moves a little, the valve opens, pressure increases in bag until it returns to the pre-set level More weight/more pressure. Now a sudden change in weight, like pulling out from under a trailer, or dumping a load, can cause the height to jump up.
The OP is much more likely to have issues over-extending than over pressure, unless he hooks up another compressor.
