New MH airbag operation

[RWjSIM2003]

Just purchased a 2014 Fleetwood Discovery DP MH. having some issues understanding the air bags and looking for some help. I have a toggle switch that says lower and auto. My understanding is that on auto the chassis will auto raise and lower.

Took the MH camping this weekend started MH let airbags inflate and raised jacks. Went to release the parking brake and air pressure dropped to 85 with foot on brake the bags were slow to get back to 120psi. I am surprised that every time I release the break that I lose air.

Am I doing something wrong? How do you operate the airbags on your coach?

[XBoater]

I noticed you were looking at a Winnebago 42E, why did you decide on the Fleetwood instead, if you don't mind me asking.

[RWjSIM2003]

Thank you all for the input. I have a much better understanding of the airbags and how it all works. Safe Travels

[Rollnhome]

Gasman the two gauges read very close to the same. I understand in static mode there is no demand for air supply to air ride, but traveling down the road and you lose available pressurized air to air leveling system you lose your nice smooth air ride.

[Rollnhome]

Bshpilot.
I think it is better to lower air bags before leveling. This lets MH drop and less stroke on jacks to level and lower center of balance when level. With air not released jacks have to extend farther and coach will set higher when level. This could "stretch" airbags putting undue stress on them. The jacks always level up, that is why I think it is best to start leveling at the lowered position. Also this is what the factory recommends for my Discovery.

[bshpilot]

Gasman2 reminds me - its not necessary to "LOWER" the coach before raising the coach or deploying the jacks...the right height control will take care of that.

once i figured out what the right height control valve was doing, i stopped dumping (or lowering) my suspension & just let the jacks do it.

[Gasman_2]

Rollnhome wrote:
Gasman I probably should have said monitors "Available" air for air ride system. But in simple terms it monitors air ride air. If it goes to zero so does your ride.

. The air pressure in the air ride system will only change if the ride height control valve calls for move or less air pressure to maintain ride height. You can drain all of your Air tanks and the pressure in the air ride would remain the same if the ride control black valve does not move. Of course over period of time the air system will leak off depending on how tight the system is. Rollinhome what is the reading on each of your air gauges when the air system is air up? I'm betting they are nearly the same. The air pressure on my tag is 40 lbs not even close to what my air gauges indicate

[Rollnhome]

Gasman I probably should have said monitors "Available" air for air ride system. But in simple terms it monitors air ride air. If it goes to zero so does your ride.

[Gasman_2]

Rollnhome wrote:
Lower is to dump air. Auto is to fill airbags and maintain ride height. To level lower (dump air) in netural with park brake on, then engage jacks to level. To get ready to go reverse procedure. Raise jacks. When jacks are raised flip switch to auto. Let air bags fill and build air pressure. Two air guages one is for brakes two is for monitoring air ride. This is how my Discovery operates. I admit I do at times flip to auto while the jacks are raising just to let it start filling bags sooner.

. The two air gauges represent the air pressure in the dual brake system as required by FMVSS 121. These gauges do not represent what is in the air ride only what is available. I guess you could have a third air gauge that would indicate the pressure air ride, but I have only seen those on trucks with air left axles .

[Trackrig]

RWjSIM2003 wrote:

Took the MH camping this weekend started MH let airbags inflate and raised jacks. Went to release the parking brake and air pressure dropped to 85 with foot on brake the bags were slow to get back to 120psi. I am surprised that every time I release the break that I lose air.

Am I doing something wrong? How do you operate the airbags on your coach?

The air brakes and the suspension air bags are not related to each other, other than they both operate off of air pressure. When you use the air brakes, they are NOT taking air from the suspension air bags. There are separate air tanks that supply air for the brakes.

When you use the brakes, air has left the brake air tanks via the brake peddle you're pushing. This activates the brakes. When you take your foot off of the brake peddle, the air can't go back into the tank, it's discharged out into the atmosphere.

The MH air compressor will continue to put out air. If the brake air tank is below it's maximum pressure limit, the compressor will refill the brake air tank back up to its max air pressure setting. If the tank is up to its max pressure, the air system will dispose of the excess pressure into the atmosphere. You will hear the air system discharging the excess air pressure every couple of minutes. You'll year a loud PISHHHHH.

As others have said, the air bag control switch will lower or bleed the air pressure out of the air bags when its in the lower position. When you flip it to auto, the air system inflates the suspension air bags "automatically" to the correct air pressure. Auto does not mean that it is automatically raising and lowering or increasing and decreasing the air pressure in the suspension air bags.

I have an Excursion which is the same as a Discovery.

Bill

[Rollnhome]

Lower is to dump air. Auto is to fill airbags and maintain ride height. To level lower (dump air) in netural with park brake on, then engage jacks to level. To get ready to go reverse procedure. Raise jacks. When jacks are raised flip switch to auto. Let air bags fill and build air pressure. Two air guages one is for brakes two is for monitoring air ride. This is how my Discovery operates. I admit I do at times flip to auto while the jacks are raising just to let it start filling bags sooner.

[bshpilot]

in auto the bags will do their best to maintain ride height & a level ride.

dropping the jacks (or raising the coach) will let air out of the bags (as it raises the frame)....this is normal.

when breaking camp you should RAISE the jacks (lowering the coach), then start the coach and let the bags fill until the compressor cuts-out (or shuts off).

each time you press the brake pedal you use some air from the tanks (press harder and you'll use MORE air)....once air pressure drops below 100 or so lbs the compressor will cut-in (aka turn on) and refill the air tanks (to about 130 psi) where once again the compressor will cut out (aka turn off).

your brake air supply is based on the PRIMARY air pressure gauge.
the airbags are usually represented by the SECONDARY air pressure gauge.