airbag suspension

[jasonjason]

G'day, Just baught a 1986 Austral Tourmaster to turn into a motorhome.

I noticed that once the bus has been stopped for a while the rear airbags deflate and the back end drops down, but the front ones dont deflate.

Is this normal or do I have a leak in the back somewhere?

[makeminea2stroke]

Hi

Congrats on your purchase

You are right on both counts, yes you do have a leak somewhere, but it is also pretty normal.

Cheerz
Glen

[jasonjason]

Thanks Glen

Now im still confused (thats not hard though)

Is it normal it has a leak or is it normal the rear sags?

Jason

[makeminea2stroke]

Hi Jason

i believe It is pretty normal for them to leak and once the air leaks out the airbag deflates it sags. On the ones I've seen it is mostly the rsend that does it, but possible for front as well.

Cheerz
Glen

[boronia]

Air bags can deflate through leakage:

1. the bag has become porous from age, or otherwise damaged
2. the sealing surface where it sits in the cradle has gone, again possibly age related
3. a faulty valve allowing air to bleed out

If the rear is going dowen in less than around 6 hours, it would be advisable to get them checked.

[jasonjason]

Thanks guys.

Time to get out some soapy water and go to work finding leaks

The fronts dont go down at all but the rears are flat in a few hours.

[kelvin12]

Any of the above and more. Loose connections at any of the air bag connections or the taps directly above the air bags themselves, leaking levelers, or as in my case a pin hole in the weld on the air bag mounting plate. Chafe holes where the pipes rub against other bits. I found the odd loose hoses fitting but the pin hole was the worst offender, still is as its a bugger to get to.

I see you are a man of discerning taste, King of the Outback in their day........ ran rings around the other clunkers.

Looking forward to seeing you progress.

Dirk

[kelvin12]

Jason,

Meant to add to the above, If you are interested there is a group of us bus converters here, http://www.motorhomeconversion.com.au/links all working away on several makes nowadays, also a buyers group you might be interested in and a good deal going on alloy rims. There is a lot of DIY help there that you might find helpful.

Dirk

[jasonjason]

Thanks Dirk. Now I have a few more things to look for

Also I do know the motorhomeconversion site well. I've lost count of how many times i have been through that site, but I keep going back as its full of usefull stuff

Jason

[plough]

Hey mate, if the airbags are deflating that quick (over a few hours) you should be able to hear were the leak is comming from.

[jasonjason]

yeah ive found one leak already plough but im not sure what the gadget is. Its in the electrical panel so im assuming its some sort of pressure sensor or something. It would be good to get a manual for the bus. Ive got a friend with a bus who is also a diesel mechanic so im going to pick his brains a bit

[plough]

Any chance you can post a picture? Height valves are mechanical and would be near the airbags, they fail every few years. So it beats me what you have.

[Romen2]

I have installed dump vavles front and rear on our SL200, takes about 5 days to drop otherwise, the air will always leak, dump vavles get it down in seconds so we can set up.

[adrianglock]

I think this is standard to bus that has kneeling system! It lowers that front so the passenger can easily access and step on the door.