Air Suspension Question

[johntelling]

Sorry if this has been asked before.

When starting up, I am wondering if it is best to wait until full air pressure is reached before switching the air suspension to 'automatic', or just flip the level over as soon as I start the engine?

Thanks,

JT

[rpelatt]

I wait until full pressure is reached and the buzzer has turned off before hitting the button for "automatic"

[dickandlois]

JT, Could you post the Make, Model and Year of your coach, also the chassis manufacture.

On my coach you need to have the switch in auto when starting or the air ride will not air up.

There are different wiring setups regarding the air valve operation that have been used over the years.

Rich.

[johntelling]

Rich, It is a 2005 Fleetwood Excursion on a Spartan chassis.

JT

[dickandlois]

JT,

Your getting close to needing a haircut, are your pet clean shaving? LOL

Your wiring is not connected to the ignition switch from what I have on file.

So it looks like you can engage the air ride before or after you start the engine to fill or dump the Air Springs.

Air Ride wiring- in cab-Connector

Pin #1==Green wire to dump circuit-wire at valve is Light green

Pin #2==Blue wire to fill circuit-wire at valve is light blue.

Only the Green and blue wires at the valve connection-2 pins

Pin #3==Black / Ground point inside cab. Most likely at the common dash grounding point.

Rich.

Note- from the drawings it looks like the Engine neutral safety switch and the park brake need to be providing a ground for the Start relay to engage. The Chassis builder may have added a slide(s) IN switch to the sequence before the engine will start?

[johntelling]

Thanks, Rich.

The problem I am having (maybe I should have started with this) is that it sometimes takes several minutes (as much as ten) for the air bags to start filling. It sounds as if there is an air leak, but that eventually goes away. As soon as the air stops hissing, the rig starts to rise, and then stays up without any issues.

My puppy Leonberger is a lot better looking that I am, hence the picture!

JT

[dickandlois]

JT,

Are you able to get under the coach SAFELY? With the parking brake set "please" and spray some soppy water around the area you hear or think the air is escaping. Should see some bubbles form or bubbles popping quickly it there is a bigger leak.

Not knowing what items have been serviced, in regards to the air compressor drier filters and how often the manual air bleeders have been pulled to vent off any water buildup in the primary and secondary air tanks, makes it difficult. So could you post all of the service that has been done on the air brake and air ride systems for the group.

One seemingly unrelated question, how long has it been since the engine air filter and intake system have been serviced?

Rich.

[tbutler]

My preference is to wait for the air pressure to rise enough to stop that annoying buzzer (at 90 PSI on our coach), then let the pressure build to about 115 PSI and engage the air bags. That way when the pressure drops as they inflate it won't go below 90 and the buzzer isn't heard from again. I don't think it makes any difference unless you do have some kind of air leak problem. If there is an air leak, it should be addressed as soon as you can get it fixed

[Afishhawk]

John,

I hope you got your question answered.

While you have these knowledgeable guys helping you out I would like to ask a similar question of a problem I am having also. I'm not trying to hijack your thread but its along the same line of problems.

I have a 2007 American Traditions coach with a Spartan chassis. I just purchased it last fall and its my first coach so I have a lot to learn.

This coach has an intermittent problem holding air when it is parked. Sometimes the coach will stay up on its air bags for days and other times either the front or back will go to rest, sometimes just one or the other and sometimes its both. Is that common?

My bigger problem is that after being set up for a few days and preparing to travel quite often the front air tank will not go above 75 # of pressure. Even after hi-idle for ten minutes or so. Sometimes I will reset the Power Gear controls, do a manual air dump and then reset for travel in hopes it will correct itself. Sometimes it works and other times you just have to be patient and wait it out.

Is there a valve in the system that could be sticking? I do not have confidence that it will always eventually air up and I feel one day I may be stranded where I am and require a service call. I bet those aren't cheap and who knows if the service tech would know how to repair it.

Last fall I took it to Spartan Coach in Charlotte Mi. and after two days of soap suds and a new air dryer $1200 later it did the same thing the next morning. Grrrr.

Any ideas?

[dickandlois]

John,

Welcome to the FMCA Forum!

Welcome to the learning curve we have all been on and if we trade coaches - it starts all over again!

For starters:

Try this when the gauge(s) do not go above 75 psi.

Make sure the air dump switch is in the auto mode, then turn off the engine and restart it. See if the guage reading goes up to it proper level ! What happens?

Have you had the ride height checked for the proper height? There are 3 valves, one for each corner of the front coach and one control valve for the rear. If they are not set to the same height, then any motion inside the coach will cause the system to use more air trying to maintain the out of spec. settings and some other strange things can happen.

You mentioned that the repair shop used soap looking for leaks, but some times the manual and auto dump valves leak and then reseal.

Did the service center mention the condition of the air dryer elements?

Rich.

[Afishhawk]

Rich,

This is Fishhawk, Thank you for your response.

Spartan replaced the air dryer and filter and a valve near the dryer because they said it had some small air leaks and there is no rebuild kit available. I feel it may have been a shot in the dark for them and it didn't fix the problem. For some reason I thought because it was a Spartan chassis they would be able to isolate the problem and identify it rather easily but that was not the case here.

I have not had the ride height checked. When this occurs the front stays down completely and does not even attempt to rise until pressures exceed the 75 # threshold. You said to have the controller in the "auto mode" I will do that next time it occurs and see if it makes a difference. I believe I normally press the "travel " button, and maybe to early in the cycle. Next time I will also wait until the air is completely up to pressure before I press the travel mode. Maybe this would allow the higher pressure to free a sticky valve if that was the case. I'm kinda at a loss and Spartan says they will look at it again but asked "How much do you want to spend on it'? I just don't want to get stranded somewhere so I would like to get a handle on this before it happens.

Is it possible that the malfunction is in the Power Gear dash control? I kept assuming it was in a valve below but I have no experience to base it on.

[jg053047]

If your Tradition is the same as my Eagle I will tell there is a switching valve near the front area of your coach that is activated electronically through the controls inside that you are familiar with.
I had to replace this master valve on a Tradition I had some years ago and that same valve is on my 2000 Eagle. It would not switch to level the coach all of a sudden after having issues somewhat the same as your describing.

If you are anywhere near Spartan Chassis I would revisit them and retell your symptom. But get there attention and make them listen.they have a pretty good reputation for service so I hear.

I also encourage you to look into joining a chapter of ACC or A.CA and get connected to the ACA yahoo group forum to discuss your issues. You will get answers specific to you Tradition from lots of members. They have bailed me out of lots over the years.

Welcome to FMCA this is a great community of fellow RVers
Jim G

[Afishhawk]

Jim,

I appreciate your inputs.

I think we are on the right track with either the dash control or master valve you mentioned. When I mentioned "valves" to Spartan they kinda blew it off and said there are a lot of valves under there and it would be difficult to know which one was causing the temperamental or intermittent problem without it actually failing at the time when tested.

They didn't want to just throw parts at it without knowing which one it needed. One would think from the described symptoms they could isolate it somewhat.

I will check out the yahoo group you suggested also.

Thanks,

Bill

[dickandlois]

Fishhawk, The fact that you did have an air leak in the drier and they fixed it is not all bad. Leaks tend to get worse over time.

Regarding the leveling system, Intermittent problems can be very hard to find and I'm thinking that Spartan did not want to charge to just start throwing parts at the problem an hope they fix it.

From one of my prior posts in this thread, I posted the wiring colors.

So it looks like you can engage the air ride before or after you start the engine to fill or dump the Air Springs.

Air Ride wiring- in cab-Connector

Pin #1==Green wire to dump circuit-wire at valve is Light green

Pin #2==Blue wire to fill circuit-wire at valve is light blue.

Only the Green and blue wires at the valve connection-2 pins

Pin #3==Black / Ground point inside cab. Most likely at the common dash grounding point.

The system power connection(s) could be an issue and have a intermittent connection.

When I mentioned placing ride in the auto / travel mode and restarting the engine, that recycles the dump valve(s) and things might air up. Should that be the case then I would look into the possibility of the valve not cycling or a bad seal, internal to the dump valve.

Rich.

[gbrinck]

It's normal that the air suspension receives no air until the minimum pressure for air brakes (60-70 psi) is reached. The air systems primary requirement is to provide air pressure to the brakes. Everything else is second or lower priority. The coach air compressor has a huge capacity, so it can usually produce enough air pressure to overcome anything but a huge leak. Leakage slows it down, but rarely stops the suspension from air up fully.

I'm not familiar with your AUTO switch - there is no such thing on my American Coach (also a Fleetwood product). Mine just builds air pressure and brings systems online as sufficient air becomes available. Do you have to manually dump air to lower the chassis and deploying the jacks? Or maybe what I'm asking, is AUTO the opposite position from "DUMP"?

Finding an fixing leaks is kind of an art. You don't especially need a Spartan chassis expert, but you do need somebody with some experience with air brakes and suspensions and knows how to test for air leaks.

[Afishhawk]

Gbrinck,

My Power Gear system has four main controls other than the raise and lower buttons when using the Manual mode.

They are TRAVEL, AUTO, MANUAL, and AIR DUMP.

Depending on the terrain determines which modes I use. To avoid lifting wheels off the ground I will use the MANUAL mode.

I have not read a manual so not really sure if I am doing it correctly or causing some of this myself but sometimes I will dump the air prior to setting the jacks down if I am using the MANUAL mode. The AUTO mode does it all along with self leveling. When using the AUTO mode I do hear it dump air at times but not sure if it does all the time but would assume so. My goal was always to maintain the lower profile for all practical reasons when possible. I cant say there is a common denominator that creates the problem but will now try to pay closer attention to circumstances that appear to create this.

Rich,

With all that info it sounds like I have to trace down a few things to make sure I have good connections.

I'm sure over time I will understand it more and be able to isolate the problem.

It sure is nice to have these forums available for us rookies to get educated !

Thanks Guys,

Bill

[Afishhawk]

^{Update on the air problem.}

Turns out the "air governor" was needing replacement. Works great now, very dependable and airs up quickly. 

[Afishhawk]

On 4/4/2015 at 8:51 PM, johntelling said:

Thanks, Rich.

The problem I am having (maybe I should have started with this) is that it sometimes takes several minutes (as much as ten) for the air bags to start filling. It sounds as if there is an air leak, but that eventually goes away. As soon as the air stops hissing, the rig starts to rise, and then stays up without any issues.

My puppy Leonberger is a lot better looking that I am, hence the picture!

JT

John,  I have had the same hissing sound when airing up and the sound also stopped when the pressure was able to build.

It seems like we determined it was a dump valve that may not have reseated and leaking causing the hissing sound. It was more apparent when under low use conditions verses when we went out weekly. That made me think higher frequency of use was keeping things moving freely. I have not heard it since replacing the air governor. 

[blakeloke]

AFISHHAWK,

Glad you found the problem.  I had similar issue with our coach leveling system not leveling, and when level, going out of kilter after a day being parked.  Long story short (my previous posts) we replaced several things.

First was the Air Dryer and Filter.  Second was the air leveling manifold.  Finally, the Air Governor.  Each of those helped a bit but none totally solved our issues until the replacement of the Air Governor.  Best thing was that there are some real experts on this Forum that helped us diagnose and repair.

I'm still looking for a small leak somewhere upstream of the air leveling system (again with the help of some of the experts here) but frustration level is WAY down now that the coach stays level when parked.

Sorry I hadn't logged on sooner - we are at Talledega for the races - and when I started reading your post my first thought was the Air Governor.

Blake

[jleamont]

Blake, glad you got most of it corrected!