How long should air suspension hold air?

[marka]

Howdy,

We have a new-to-us '99 Dutch Star. When parked for a few days, the front suspension seems to be slowly loosing air pressure. IIRC, over a couple days the front was down just like you'd dumped the air, with the rear at ride height.

When I started it up this morning, front and rear air pressure were both around 80psi as I recall. The front suspension inflated, and it seemed to drive fine. After running for a bit, front and rear air pressure was at ~105 psi or so and stays there.

Is this normal, or a cause for concern? I'm new to air suspension/brakes...

Unless someone tells me otherwise, I think when we park it for more than a couple days we'll dump the air and use the jacks anyway, so I'm not particularly concerned about a very slow leak, but being new to this I figured I'd ask if this was an early symptom of a bigger problem.

Thanks!

Mark

[Jim Stewart]

You probably have a small air leak and this tends to be normal in many coaches, especially as they age. If it holds air while running, you are usually OK. You may want to try to find it, with air in the bags, use a soapy spray mixture and spray all air lines and fitting, you may find it.

[wa8yxm]

Some years ago when I was pulling a trailer I addd air-bags to the rear springs on what is now my towed.

When I checked the pressure earlier this year it was just where I"d set it.. several years ago.

[AFChap]

Sounds pretty normal compared to what I have heard other owners say, and how my coach performs. I don't know what lelveling jacks your coach has, but HWH advises to use the leveling jacks when storing the coach. They say it won't hurt the jacks at all, and it takes some pressure off the tires helping to preserve them a bit.

[rowesort]

A couple of days is all mine hold air with the front axle worse than the back; however it is a quick fix, my HD mechanic friend says the air lines are just a push & pressure fit. He removed one which was going down overnight cut off the end with a pocket knife and reattached. And now the air bag holds air about 3 days.

[skippers_1]

I have the same new to me 99 dutch star and it does the same thing, I DID GO UNDER and tighten all the air fittings I could find and it still looses air slowly just the front .
Like other said mine runs down the road with plenty of air, so I live with it.
Rich

[DutchStar38]

Same here. If I don't put the jacks down the front will squat overnight. I do however, always use the jacks when we park at a camp or at home in stroage. Pressure is maintained when running.

[samert111]

Our Tradiiton would loose all the air pressure completely within a couple weeks with the suspension settling within a couple days. I found that all 3 ride height valves were leaking and both the manual tank drains also were not completely re-sealing after pulling the cables. Have since changed out all the ride height valves and the tank drains. It still looses air slowly but at least the suspension seems to be staying up.

[wa8yxm]

How long should it hold air.. Before my towed became a towed, it was a tow-vehicle for a trailer.. The trailer was a bit "heavy" for it so I put a set of Air-Lift air bags on it

Last time I checked them they still had the proper amount of air in them.. And I'd not checked them for at least 2 or 3 years.. yes, years.

[PaulO]

My 98 Dutch Star does the same as far as losing air. I have come up with a theory - If you do not deploy the hydraulic jacks and suspend the motorhome, any motion of the motorhome such as wind blowing or people walking in it can slightly activate the air suspension leveling valves. If you move the motorhome around enough, you deplete the stored air supply in your tanks and the ability to resupply the bags ceases resulting in loss of height. I believe this to be true for two reasons - one, after parking the MH without deploying the jacks, you can actually hear the valves letting air in and out of the bags when you exit the coach. Two - the more I am in and out of the coach the quicker the air supply depletes. What do you think?
Paul

[gesmone]

I have a similar problem. My front and rear tanks can be fully filled. (140 PSI) After three days my front tank will be down to 40 to 50 PSI. This air loss is worse now than a year ago. Spartan says that there is no reason for concern. My concern is as the coach ages is the leak going to get worse? I have friends that don't loose 5 PSI in that time period.

[94-Newmar]

My largest loss of air while parked is from the air assisted portion of the Cruise Control setup. I was told it always keeps a regulated 40 psi to the CC assembly itself - so once we shut the engine off you can hear it bleeding down as the supply side still has 120lbs in it. Once both tanks reach 40 psi the hissing stops Perfectly normal I am told for my model year.

[skippers_1]

Quote:

Originally Posted by PaulO My 98 Dutch Star does the same as far as losing air. I have come up with a theory - If you do not deploy the hydraulic jacks and suspend the motorhome, any motion of the motorhome such as wind blowing or people walking in it can slightly activate the air suspension leveling valves. If you move the motorhome around enough, you deplete the stored air supply in your tanks and the ability to resupply the bags ceases resulting in loss of height. I believe this to be true for two reasons - one, after parking the MH without deploying the jacks, you can actually hear the valves letting air in and out of the bags when you exit the coach. Two - the more I am in and out of the coach the quicker the air supply depletes. What do you think? Paul

I dont use the jacks when in storage mabe I should, as far as going in & out causing the air to leak out I normnally dont go in & out once it is parked, still loses air

[sailor_lou]

Although losing air appears to be the norm, I don't believe it has to be that way. As suggested above, check all the fittings with soapy water and tighten accordingly. My MOHO usually sits for 3-4 weeks between trips and if the suspension does change, it's not even detectable. When I start the engine, pressure is typically within 10 lbs or so of max.

Lou
05 Travel Supreme 38DS04
Spartan Mountain Master chassis