I have not seen a schematic for the air system and would be doubtful that they exist. The 120 volt pump on my coach turns on at 72 psi and shuts off about 95 psi. A worn pump will build up pressure initially but as the pressure increases it will take more and more time to bring the pressure up the last 10 psi or so. These compressors will overheat if they have to run for lengthly period and may shut off on a thermal overload. I had mine replaced at the factory recently because it would come on at 72 psi, pump up to about 80 psi in a 3-5 minutes, then run for 30 minutes or more trying to get the last 10-15 psi into the tank. At times it would shut down before reaching the 92-95 psi range due to overheating. The new pump takes about 3-1/2 minutes to bring the pressure up to 95 psi from 72 psi.
If you have the drivers side up after leveling then listing after a short time period, you likely have a slow leak in the right rear air bags or the air lines or fittings running from the solenoids in the rear to air bags.
My 1992 has an HWH air leveling system and the remainder of my comments are based on the operation of that system.
My coach has 12 solenoids in the right rear engine compartment for the air system and 6 more solenoids for the air system in the front left of the coach which you have to access from underneath. I had the solenoid that dumps the right rear sticking so I had all 18 replaced as a precautionary/routine maintenance measure as it appeared that they were all the original 1992 solenoids. They are about $87 each for the parts.
If the coach never levels properly when in LEVEL mode, there is a level sensor, which on my coach is in the drivers side compartment directly behind the mid-entry door hanging from the top of the bay on the center line of the coach. That sensor is adjustable if the coach thinks it is level when it is not. That part of the circuit ONLY works when you have the leveling control in the LEVEL mode rather than the TRAVEL mode. Leveling in the Travel Mode is controlled valves connected by rods to the axle at the center of the front axle, and on each side of the drive axle.
The air bags require a LARGE volume of air to inflate. Trying to raise even one corner of the coach very much typically requires the engine running on Fast Idle to produce enough air.
|