# loss of pressure on air suspension



## tombar

I had air suspension put on my Compass Calypso last May by Gasworksair via this forum and it has been good. I last used the van 2 weeks ago at its usual pressure of 90 psi. Today, I noticed it was low at the back and leaning to the left and found one was at 84.5 and the other at 10 psi. Gasworks air doesn't seem to exist any more. Can anyone tell me what may have caused the loss of pressure on the suspension and is it a matter of getting it all replaced?


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## icer

Wow that is a very high figure to run your system at, I run mine at 3.5 bar at that is quite high. yours would be about 6.2 bar.

Is Gasworks air suspension Ltd no longer trading then?

dont know where you are but would use google to find a repair shop

Ian


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## tombar

*suspesnion*

For the pressure, I was told by Gasworksair that Firestone say to use them at 10-100 psi and I was lead to believe the kit is a Firestone one, though I don't have any evidence for this.

The bags have only been on 9 months, so I'd have thought there might be a warranty, but haven't yet found how to contact Firestone.

According to the Internet, Gasworks air was dissolve in January this year.


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## raynipper

Do they have a shrader valve to blow them up again?

My Winnebago with a Chevy chassis had air bags all round. The recommended pressure was 60 psi. They had valve extenders to top them up as and when needed.

Ray.


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## tombar

raynipper said:


> Do they have a shrader valve to blow them up again?
> 
> My Winnebago with a Chevy chassis had air bags all round. The recommended pressure was 60 psi. They had valve extenders to top them up as and when needed.
> 
> Ray.


Yes, two Shrader valves


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## Ian_n_Suzy

icer said:


> Wow that is a very high figure to run your system at, I run mine at 3.5 bar at that is quite high. yours would be about 6.2 bar.
> 
> Is Gasworks air suspension Ltd no longer trading then?
> 
> dont know where you are but would use google to find a repair shop
> 
> Ian


Hi,

I recently fitted a Dunlop System to our 7m Van and we run them at 37psi with the Van more or less fully loaded to 3850kg (I tried at 50 and found it too hard so gradually lowered it).

This system is also rated to 100psi (or it may be 110), but running it at that would be rock hard.

I presume the valves must not be linked if one is at 84.5 and the other at 10, so you should be able to try to re-inflate it, though I would think something must be wrong for it to go so low (maybe check the valve?).

Good Luck


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## tombar

My van was terrible for rolling and getting pushed sideways by even a car overtaking - strong winds had it completely heeling over. I tried lower pressures, but didn't find them effective. 

The pressure drops back to virtually nothing in less than an hour. It inflates in jerks and the van drops down in jerks - not a gradual leakage, it seems


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## cheokee

Sounds like the valve leaking.


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## DTPCHEMICALS

I run ours at 35psi at the highest.
After checking the valves, if they are ok then,
mix a solution of soapy water in a spray bottle.
If you do not have one mix in a jar or similar.
Pump up your system. Spray soapy solution onto the pipe joints and then the air bags. If using a jar paint solution with a paint brush.

Just like when you were a kid looking for a puncture on your bike inertube.
When you see a stream of bubbles apearing you have found your leak.

Dave p


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## raynipper

DTPCHEMICALS said:


> I run ours at 35psi at the highest.
> After checking the valves, if they are ok then,
> mix a solution of soapy water in a spray bottle.
> If you do not have one mix in a jar or similar.
> Pump up your system. Spray soapy solution onto the pipe joints and then the air bags. If using a jar paint solution with a paint brush.
> 
> Just like when you were a kid looking for a puncture on your bike inertube.
> When you see a stream of bubbles apearing you have found your leak.
> 
> Dave p


I do that when looking for gas leaks now I don't smoke.

Ray.


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## provencal

We have Air Ride and have to top the pressure up to about 40psi, about once a month, to keep in the green segment.

I assumed that the rubber had become porous with age and this was a normal requirement. Do other members have completely airtight systems?

Brian


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## DTPCHEMICALS

Ray :lol: :lol: :lol: :lol: 

Gas leaks can be a bit iffy.

Dave p


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## dodger148

Like some of the others I run at 35/38 ish and would suspect the valve cores which are readily available from accessory shops or tyre companies.

I think where the 100lbf/in2 comes in is when fitting it is suggested that you inflate to 80/90 lbs to check the joints are ok and dont think this is normal running pressure

I was concerned about our Airides at one stage but was assured it was the cold weather and true enough during the summer I dont need to inflate so much (say every couple of months)


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## tombar

Just to clarify the situation - I'm a motorhome simpleton, so:

Does check the valve just mean put air in and put soapy water on the valve outlet?

To look at anything else, I can't get underneath with no suspension, so presumably I jack it up first?


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## Mike48

tombar said:


> Just to clarify the situation - I'm a motorhome simpleton, so:
> 
> Does check the valve just mean put air in and put soapy water on the valve outlet?
> 
> To look at anything else, I can't get underneath with no suspension, so presumably I jack it up first?


Yes air and then soapy water around the valve. *DO NOT GET UNDER THE VEHICLE WHEN IT IS JACKED UP.*


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## tombar

Got bubbles at the valve! Now to find a new one and get it screwed in.

Hopefully that's it, so thanks everyone


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## peribro

As others have said, 35 - 40 psi is a more normal pressure. I suspect that by running at such a high pressure for so long the system has sprung a leak. Also as has been said, don't go under the van and also don't drive it any further than you absolutely have to with that differential in pressures. On my airride suspension it is possible to equalise the pressure on both sides by opening the taps adjacent to the pressure gauge. Maybe you have something like that?


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## tombar

peribro said:


> As others have said, 35 - 40 psi is a more normal pressure. I suspect that by running at such a high pressure for so long the system has sprung a leak. Also as has been said, don't go under the van and also don't drive it any further than you absolutely have to with that differential in pressures. On my airride suspension it is possible to equalise the pressure on both sides by opening the taps adjacent to the pressure gauge. Maybe you have something like that?


No taps, no gauge, just two Schrader valves and the compressor I connect to the cigarette lighter.

Will try a lower pressure again once it's operational


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## Mike48

peribro said:


> As others have said, 35 - 40 psi is a more normal pressure. I suspect that by running at such a high pressure for so long the system has sprung a leak. Also as has been said, don't go under the van and also don't drive it any further than you absolutely have to with that differential in pressures. On my airride suspension it is possible to equalise the pressure on both sides by opening the taps adjacent to the pressure gauge. Maybe you have something like that?


The Airride people told me that I could use any pressure I liked after trial and error but suggested that I use 50psi on my panel van with little overhang. I have found that 35-40 psi is about the equivalent of the standard suspension.

Clearly every vehicle is different but for a coachbuilt I would have expected at least 60psi to be the norm but I agree that 90psi would probably be far too high.


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## veevee

Drive - Rite are Firestone, they are at -

www.autovan.co.uk


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## peedee

I had Airides on my last van and used to run them between 40-50psi. I was told they have a life of about 8 years. You do have to top them up now and again. One of my bellows actually developed a leak after nine years and it was considered dangerous and the van would have failed the MOT had I not replaced them. I also had the piping replaced at the same time.

peedee


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## pneumatician

The 90psi pressure is very close to the working maximum and I would have thought too close to failure. But I do not know what the safety factor is.
You obviously have independant pressure regulation so first off the valve needs checking then the pipe connections (check as you would for a gas leak with soapy water). Next check the actual hoses and cylinders for chafing. If you have a chafed, split or leaking cylinder it I am sure will be Kaput and need replacing.
What you should bear in mind is if the max working pressure is 100psi and you have a heavily laden van going over severe bumps set a 90 psi on the upward movement of the axle the pressure will increase as the cylinder compresses and this could exceed the maximum.
I have never inflated my suspension to more than 2.4 bar (35psi) and if driven at this pressure without the motorbike in the boot the back end bounces about somewhat.
Also I do not like independant pressurisation. Imagine the potential results of a complete failure on one side whilst negotiating a bend or at speed on the motorway.
I have always used just one inflation point with the wheels balanced.

Steve


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## satco

I have a Goldschmitt dual circle air suspension on my "old camel".
(since 2010)
I have tried various settings , and found best operating pressure is
3.0 bar , when stronger winds prevail the max. pressure is 3.5 bar.

Jan


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## tombar

gelathae said:


> The Airride people told me that I could use any pressure I liked after trial and error but suggested that I use 50psi on my panel van with little overhang. I have found that 35-40 psi is about the equivalent of the standard suspension.
> 
> Clearly every vehicle is different but for a coachbuilt I would have expected at least 60psi to be the norm but I agree that 90psi would probably be far too high.


Have replaced the leaking valve and OK except for about 5 psi loss over 24 h when set at 60 psi. At 60 psi, it's doubtful if the air suspension is much better than the original springs - van wallows, and gets blown about by overtaking vehicles and wind. Am now trying 70 - at least you can hear the van lifting a little as the pressure gets above 65 psi and it lifts the exhausts to a reasonable height.


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## tombar

Just for information: I received this reply from Chris Ward of Automint who do Firestone air suspension:

Firestone bags are rated to 115psi so your ok running at 90psi. The 
inflation valve internals may have come loose over time and then popped out. On the reverse of the valve cap is the key for nipping the internals of the valve. I don't know the limit of the valve but trucks run 120psi in their tyres no probs. If you need anything in the future please let me know.


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## Jumbocruiser

Was your air suspension system specifically recommended for your van?

It sounds possible that it could be some kind of generic equipment that may be under rated for the weight of your motorhome.

I'm no expert but larger diameter air bags might be available that will give you the required lift and stiffness at lower operating pressures.

We have an air-ride system fitted by West Country Motorhomes on our Ducato based van, fortunately this is a very popular and well documented system that works well at about 35psi.


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## icer

Hi.

I have just had a look at my system details.
They are Goldschmitt their catalogue shows a 6" or 8" version available.
Given that you say it not high enough perhaps different bellows might help.

Ian


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