Airing down

[Ivan K]

8 minutes ago, BobSchmeck said:

Interesting, in our coach if i deflect the bags there not enough pressure left for the breaks and it would refuse to go into the building. LOL

Must be something about how HWH handles the dump command, like if it went into leveling mode because all the red corner lights come on. I never tried to understand it, just the way it always worked.

[Jim McGarvie]

1 hour ago, Dr4Film said:

Jim,

When I first get home all I have to do is dump the air bags to back in. Then over time the air tanks will lose all of the air until they register 0 psi on the gauge.

However, when I need to pull the coach out from under the house, I first start the engine to build up the air pressure to release the rear brake springs, then put the coach in gear and hold down the Dump Air Switch until I am completely out from under the house.

Even though your coach doesn't have Air Leveling you must have a switch which dumps the air from the bags, correct? Or does your Air Dump Switch dump ALL air from the air tanks & the bags at the same time? If so I wonder if you could alter the air system so you could just dump air from the bags separately?

Having a Knight you most likely only have four air bags to deal with.

Richard,

Nope, no switch to dump just the bags, only the entire system, bags and tank. I would love to be able to just dump the bags. And yes, we have four bags.

[96 EVO]

1 hour ago, BobSchmeck said:

Interesting, in our coach if i deflect the bags there not enough pressure left for the breaks and it would refuse to go into the building. LOL

Your coach would need air-leveling to do what your attempting to do.

[Dave Pumphrey]

I have HWH air leveling on our 2000 Dynasty, I always dump the front to get the step low as possible, then, if needed, make other adjustments to get level. With this system, dumping bags does not dump tanks...

[Jeff H]

My 06 Diplomat, with hydraulic leveling dumps the air bags but they will refill if the system pressure is high enough.  it would be nice to have a way to lower the coach without having to reduceair pressure tothe point of the low air alarm going off.

[Dr4Film]

Jeff,

I would think that having the ignition key turned OFF would accomplish that task such that the air bags do NOT refill until the ignition key is turned back on.

I wonder if there is a missing or faulty ignition lockout relay that is allowing the air bags to raise when they are not supposed to.

[Jeff H]

1 hour ago, Dr4Film said:

Jeff,

I would think that having the ignition key turned OFF would accomplish that task such that the air bags do NOT refill until the ignition key is turned back on.

I wonder if there is a missing or faulty ignition lockout relay that is allowing the air bags to raise when they are not supposed to.

You are correct but to level or move the coach I need the key on.  So to level I have to reduce the air pressure to the point it won't raise the coach which is just below when the alarm comes on.  I suppose one could wire the leveling so it did not require the ignition to be on.

[Dr4Film]

1 minute ago, Jeff H said:

You are correct but to level or move the coach I need the key on.  So to level I have to reduce the air pressure to the point it won't raise the coach which is just below when the alarm comes on.  I suppose one could wire the leveling so it did not require the ignition to be on.

Well once again the Monaco "pillow" engineers strike again. It just makes common sense (which they lacked) that you should NOT need the ignition key on to level.

Thankfully, it is that way with Air Leveling and should have been that way with Hydraulic Leveling also.

[Endeavor to RV]

32 minutes ago, Jeff H said:

You are correct but to level or move the coach I need the key on.  So to level I have to reduce the air pressure to the point it won't raise the coach which is just below when the alarm comes on.  I suppose one could wire the leveling so it did not require the ignition to be on.

On my '03 Endeavor I turn the key to the left, accessory position, to dump air and use hydraulic levelers. No alarm. Perhaps your rig will work this way?

[rvingstuff]

I've read this thread and keep wondering why everyone is "airing down." When I replaced all of my air bags, I was told that their life cycle will be extended if you DON'T allow them in the totally "aired down" position. The reasoning is that when they are flat - aired down - there is far more pressure on the sides of the bags.

 

This made good sense to me and I've followed that rule-of-thumb ever since.

 

Now, if it's the idea that your coach is too high for ease of entry and exit, I carry a simple "step" to allow for the difference in height. This - to me - is a much less expensive option to early fatigue and need for replacement of very expensive air bags.

 

Just my "2 cents."

[waterskier_1]

We had a similar discussion regarding this on another forum.  We concluded that coaches with Air Ride only (no Air Leveling), must dump everything (both air tanks) to drop the coach.  Coaches with Air Leveling (specifically HWH and maybe Power Gear) do NOT need to dump the air tanks to drop the coach.  On those systems with air leveling there are 6-pack valves (solenoids) that control routing of the air to the air bags.  When Air Level dump valve is energized only the air level valves are operational, and the ride height valves are inhibited.  Therefore, the main air tanks are disconnected from the air bags when the coach ignition is OFF.  Now if you start the engine, the coach will begin to rise as the ride height valves become energized again.  I think, but have not tested a Power Gear system to confirm it operates the same.  As previously stated, if you don't have Air Level, you don't have the 6-pack valves to isolate the ride height valves, and the main air tanks, so you have to dump everything.

Most people choose to dump before leveling to get the coach as low to the ground as possible.  It's not required because if the coach can't be leveled by adding air to the low side, the system will dump air as necessary (within it's design limits).  

I think anyone who stores their coach, and doesn't have leveling enabled (with power for the compressor), or on hydraulic jacks, the coach is going to settle all the way down eventually.

[Jim McGarvie]

2 minutes ago, waterskier_1 said:

We had a similar discussion regarding this on another forum.  We concluded that coaches with Air Ride only (no Air Leveling), must dump everything (both air tanks) to drop the coach.  Coaches with Air Leveling (specifically HWH and maybe Power Gear) do NOT need to dump the air tanks to drop the coach.  On those systems with air leveling there are 6-pack valves (solenoids) that control routing of the air to the air bags.  When Air Level dump valve is energized only the air level valves are operational, and the ride height valves are inhibited.  Therefore, the main air tanks are disconnected from the air bags when the coach ignition is OFF.  Now if you start the engine, the coach will begin to rise as the ride height valves become energized again.  I think, but have not tested a Power Gear system to confirm it operates the same.  As previously stated, if you don't have Air Level, you don't have the 6-pack valves to isolate the ride height valves, and the main air tanks, so you have to dump everything.

Most people choose to dump before leveling to get the coach as low to the ground as possible.  It's not required because if the coach can't be leveled by adding air to the low side, the system will dump air as necessary (within it's design limits).  

I think anyone who stores their coach, and doesn't have leveling enabled (with power for the compressor), or on hydraulic jacks, the coach is going to settle all the way down eventually.

Spot on, Rick. Our coach does not have air leveling, and deflating the air bags deflates the entire system, tank and all. And as you point out in your last sentence, within a couple of days our bags are fully deflated no matter what we do.

[96 EVO]

53 minutes ago, waterskier_1 said:

We had a similar discussion regarding this on another forum.  We concluded that coaches with Air Ride only (no Air Leveling), must dump everything (both air tanks) to drop the coach.  Coaches with Air Leveling (specifically HWH and maybe Power Gear) do NOT need to dump the air tanks to drop the coach.  

Yes, the Valid / Power Gear system works the same.

[Dr4Film]

1 hour ago, waterskier_1 said:

I think anyone who stores their coach, and doesn't have Air Leveling enabled (with power for the compressor), or on hydraulic jacks, the coach is going to settle all the way down eventually.

I guess this makes perfect sense for coaches with Hydraulic Jacks to dump all air first which usually takes a long time to drain both tanks and air bags too, then level, or is it not necessary when you have jacks?

Never had a coach with jacks so I don't know what the procedure is. I guess once the jacks are in place the air bags are out of play.

I do know that Monaco ALWAYS recommends deploying slides at Ride Height then leveling. Does that mean that once you activate the leveling control panel the system will dump all air FIRST then deploy the jacks to level?

Just wondering....

[eddie4ne]

1 hour ago, Dr4Film said:

I guess this makes perfect sense for coaches with Hydraulic Jacks to dump all air first which usually takes a long time to drain both tanks and air bags too, then level, or is it not necessary when you have jacks?

We always air down before storage bc it will leak unevenly.

[waterskier_1]

Richard,  tree rationale for dumping air is the same for air & hydraulic leveling, to keep the coach as close to the ground as possible.  Most don't want to have to use a step ladder to get in the Front door.   This has nothing to do with when the slides are deployed.  As you stated, Monaco says to move slides only at ride height.  This means the first thing you do is deploy the slides.  Then, if you choose, you can dump air - but you don't have to (depending oh how level the ground is).  The next thing is to level - you may choose manual or automatic, it's up to you.  The statement I made earlier holds for hydraulic jacks too;  if you have air ride, you'd have to dump all air, if you have air leveling but choose not to use it (I don't use mine), the air leveling valves are still there and continue to function.  The valves don't know you are using jacks.  The amount of time it takes has nothing to do with jacks, but rather whether the coach has air leveling or just air ride.  Other factors can also affect the time, such as clogged dump valves, but not the presence or absence of jacks.  Of course if the coach doesn't have air leveling, it will have jacks.  But just because it has air leveling doesn't mean it won't have jacks.  I prefer the solid connection between the frame and the ground - it minimizes the movement of people walking around - especially up the steps out in the slide.  I guess all the good reasons for having ride when going down the road are tree reasons I don't like it when parked.  

Yes once on the jacks, the bags are out of play, at least until you start the coach, at which time time ride height valves will cause the bags to start inflating.  I actually take advantage of that.  When I'm home, I'm leveled on the jacks, but unless I'm loading / unloading or working on something that requires a slide to be deployed, I keep my slides in (in storage) but level, so I can fire up the refrigerator.  If I need to deploy a slide, I simply start the engine and the compressor raises the coach, off the jacks (they are still extended, just no longer supporting anything) to ride height.  Then I shut down & deploy the slide.  When I'm done, I simply dump the air and I'm back on the jacks and level.... no need to re-level.

[Larry H]

On 8/10/2021 at 1:39 PM, Gary M said:

Mine requires me to pump the brakes to drop the coach. That process takes about 45 seconds but its irritating. Ill have to just use the dump switch next time to see how long it takes.

Gary, that is what I was doing—dumping the tanks. I have since been told that is bad for your system. I have a dump switch on the dash that, with the key on,  this slowly lowers the coach—so slow I open the door so I can see it going down. The tanks retain most of their pressure.

[96 EVO]

49 minutes ago, Larry H said:

Gary, that is what I was doing—dumping the tanks. I have since been told that is bad for your system.  

Larry, I don't know why anyone would consider that 'bad' for your system?

Maybe, rather than pumping the brake pedal to drain your air tanks, pull the drains on the bottom of each tank (probably lanyards in your case), and check for moisture!

That's 'always' a good thing to do!

Edited August 13, 2021 by 96 EVO

[waterskier_1]

31 minutes ago, 96 EVO said:

Larry, I don't know why anyone would consider that 'bad' for your system?

Maybe, rather than pumping the brake pedal to drain your air tanks, pull the drains on the bottom of each tank (probably lanyards in your case), and check for moisture!

That's 'always' a good thing to do!

It has to do with the way the air brakes and the park brake (two separate systems & parts) work.  Pressing the brake pedal forces the brake shoes to tree drum.  Once under about 60 PSI, the park (some call emergency) brake is released.  Pressing the Break pedal with the park brake energized is not recommended.  Some training says never do it.  More detailed info is on the web.  

[Jeff H]

21 hours ago, Endeavor to RV said:

On my '03 Endeavor I turn the key to the left, accessory position, to dump air and use hydraulic levelers. No alarm. Perhaps your rig will work this way?

I tried that, mostly because I know I can dump the air in the accessory position and would feel like an idiot for not having tried to level. The leveler does not have power in the accessory  position. Perhaps a new wiring project.

16 hours ago, Dr4Film said:

I guess this makes perfect sense for coaches with Hydraulic Jacks to dump all air first which usually takes a long time to drain both tanks and air bags too, then level, or is it not necessary when you have jacks?

Never had a coach with jacks so I don't know what the procedure is. I guess once the jacks are in place the air bags are out of play.

I do know that Monaco ALWAYS recommends deploying slides at Ride Height then leveling. Does that mean that once you activate the leveling control panel the system will dump all air FIRST then deploy the jacks to level?

Just wondering....

If I am close to level I will not dump.  If the jacks need "room to work" I will dump.  of course as soon as you lift with the jack the ride height valves kick in and star dumping air trying to lower the coach.  They continue to drain until the bags are empty but not the tanks whether the key is on or not.

[Steven P]

I typically get parked, deploys slides, then dump air, then level (jacks only).  I do not have air leveling,  only hydraulic jacks.   My air dump takes around 1 to 2 minutes, long enough that I put a clothespin under the switch so I can do other things.  Once it gets to about 30, it stops on its own and if I want it to get to zero, I pump the brakes or just wait a couple of days and it leaks out.  My coach dumps all driver side air before the passenger side, causing a "lean to the left" for a little bit.  

Recently, I've started leaving the jacks down when starting the engine and airing up and retracting the jacks once the bags are partially full.  Due to the left lean, I will not be leaving the jacks down (as in storage) and dumping air as I worry what that angle of lean could do to the jacks.  When airing up, there is no angle, so the jacks are straight.  

I watched a new model Tiffin level and dump and build air very quickly one day.  Looked like the cars with hydraulics.

[dl_racing427]

10 hours ago, waterskier_1 said:

It has to do with the way the air brakes and the park brake (two separate systems & parts) work.  Pressing the brake pedal forces the brake shoes to tree drum.  Once under about 60 PSI, the park (some call emergency) brake is released.  Pressing the Break pedal with the park brake energized is not recommended.  Some training says never do it.  More detailed info is on the web.  

The park brake applies under low pressure, not releases.

I've heard that the combined force from the spring brakes and the service brake can bend the linkage or brake shoes.
I've fanned the brakes to drop pressure faster, but I don't press the brake pedal hard, only enough to repeatedly flow some air through the system.

 

[96 EVO]

10 hours ago, waterskier_1 said:

It has to do with the way the air brakes and the park brake (two separate systems & parts) work.  Pressing the brake pedal forces the brake shoes to tree drum.  Once under about 60 PSI, the park (some call emergency) brake is released.  Pressing the Break pedal with the park brake energized is not recommended.  Some training says never do it.  More detailed info is on the web.  

Yeah, that hasn't been true since they developed anti- compounding valves, many years ago.

Here's a piece from a CDL air brake training manual;

This adding together of the two forces can potentially cause damage to slack adjusters, s-cams, brake chambers, brake shoes, and brake drums (the foundation brake components).

Yet, this problem is now obsolete, as the majority of trucks are equipped with an anti-compounding valve.

This valve prevents the service brakes from being applied if the parking parking brakes are engaged.

Despite this advance in technology, a significant number of driving instructors are going to get “right torqued” if a students makes a heavy service brake application and the parking brakes are engaged!

[waterskier_1]

1 hour ago, dl_racing427 said:

The park brake applies under low pressure, not releases.

I've heard that the combined force from the spring brakes and the service brake can bend the linkage or brake shoes.
I've fanned the brakes to drop pressure faster, but I don't press the brake pedal hard, only enough to repeatedly flow some air through the system.

 

I think we are saying the same thing, just using a different point of reference.  The park brake is held off (not engaged) by air pressure.  Once that pressure is reduced below around 60 PSI, the brake is "released" for being held off by air pressure, and allowed to engage due to the springs.  

 

58 minutes ago, 96 EVO said:

Yeah, that hasn't been true since they developed anti- compounding valves, many years ago.

Here's a piece from a CDL air brake training manual;

This adding together of the two forces can potentially cause damage to slack adjusters, s-cams, brake chambers, brake shoes, and brake drums (the foundation brake components).

Yet, this problem is now obsolete, as the majority of trucks are equipped with an anti-compounding valve.

This valve prevents the service brakes from being applied if the parking parking brakes are engaged.

Despite this advance in technology, a significant number of driving instructors are going to get “right torqued” if a students makes a heavy service brake application and the parking brakes are engaged!

The 2005 Commercial Driver License Manual from some states (Rhode Island is one) still have the warning, without the commentary that it is obsolete.  I'm not sure how many years ago the change was made, nor am I sure that it was 100% incorporated in every single brake system at that time.  In any case, Monaco added a Dump Valve so you wouldn't have to feather the brakes.  I suspect that the reason it's taking so long is that it hasn't been used and the dump valve is (partially) plugged.  I have never seen a Monaco Owners Manual that recommended other than the dump valve to dump the air.  Why not fix what's broke versus finding a work around? 

[Gary M]

On 8/12/2021 at 12:22 PM, Dr4Film said:

I guess this makes perfect sense for coaches with Hydraulic Jacks to dump all air first which usually takes a long time to drain both tanks and air bags too, then level, or is it not necessary when you have jacks?

Never had a coach with jacks so I don't know what the procedure is. I guess once the jacks are in place the air bags are out of play.

I do know that Monaco ALWAYS recommends deploying slides at Ride Height then leveling. Does that mean that once you activate the leveling control panel the system will dump all air FIRST then deploy the jacks to level?

Just wondering....

On my coach no! I have to dump bags separately. Jacks are totally separate process. I am going to try not using the brake pedal next time to drop the coach. It takes about 45 sec to dump using both switch and pumping brakes which is how my manual instructs from what I remember anyway. The following is my basic procedure for leveling.

This only my opinion! Jacks are for stabilizing not leveling. Level with whatever u choose under your tires then stabilize with jacks. I use four sets of (21026) “Camco Fasten XL 2x2 Leveling Block - Interlocking Design”. Just my opinion. Smile 😀

 

1- Pick as level of a spot as possible.

2- Use whatever means of leveling your coach by placing supports under your tires to bring coach as level as possible while at ride height.

3- Move slides out.

4- Dump air or not.

5- Lower jacks to stabilize.

 

If not dumping air, you should also place supports under jacks so as to use minimum amount of fluid in reservoir.

 

This only my opinion! Jacks are for stabilizing not leveling. Level with whatever u choose under your tires then stabilize with jacks. I use four sets of (21026) “Camco Fasten XL 2x2 Leveling Block - Interlocking Design”. Just my opinion. Smile 😀

 

1- Pick as level of a spot as possible.

2- Use whatever means of leveling your coach by placing supports under your tires to bring coach as level as possible while at ride height.

3- Move slides out.

4- Dump air or not.

5- Lower jacks to stabilize.

 

If not dumping air, you should also place supports under jacks so as to use minimum amount of fluid in reservoir.