1999 DSDP another with front airbag leaking down

[RV2015]

1999 Dutch Star Spartan Mountain Master Chassis. Front bags leak down over night. Air tanks both had @120 psi yesterday afternoon, this morning front of coach leaked down, both front airbags down. Rear bags still inflated.
Both air tanks, this morning, now read @55psi.
From what I am reading I have a leak, air tanks kept trying to fill until a cutoff valve stepped in and shut the air supply off to retain minimum air in system. Also this @24 hour leak down doesn't sound normal. (?) The coach is now kneeling.
Also from what I am reading, for a newbie, I shouldn't be crawling around underneath for health reasons.
The good news is the rig is scheduled for a full service Monday. As the rig is new to me I am having everything checked, changed, inspected front to back. That was my plan regardless of maintenance records just so I know. Long winded way to ask what should I have the mechanic/technician look for? Or just soap the system and look for bubbles?
Glad I read the posts about not going under the coach, as I would have, being a newbie and all....Thanks.

[tom chelbana]

You have a leak in the air system and since you are taking it into a service location have them check it out. The leak will not stop you from traveling in coach until you get it checked out.

[Skip426]

Your problem , both tanks down to 55 psi. may indicate multiple problems.
On Freightliner the air suspension system is fed from only one tank.
If the shop isn't a Spartan facility you should try to round up an air system diagram for them to hand over when you arrive for the service .
Hope that the leak is something simple to repair, because any loss of air in the suspension; in less than a week anyway; can run the brake system short and reduce stopping power.
Going under the coach when the system is aired up to look for a leak, requires safety stands to protect yourself.

[Matador 01]

Call Chris McCord at Sparton 517-543-6400 X3235, he will tell you whats wrong. Had the same thing on my 2003 a couple years back, repair folks tried everything here, couldn't find the problem, called Chris and he said change the rear ride height valve (yes rear) and that fixed the problem. Haven't had a problem since.

[Rotten-Red]

Originally Posted by RV2015

1999 Dutch Star Spartan Mountain Master Chassis. Front bags leak down over night. Air tanks both had @120 psi yesterday afternoon, this morning front of coach leaked down, both front airbags down. Rear bags still inflated.
Both air tanks, this morning, now read @55psi.
From what I am reading I have a leak, air tanks kept trying to fill until a cutoff valve stepped in and shut the air supply off to retain minimum air in system. Also this @24 hour leak down doesn't sound normal. (?) The coach is now kneeling.
Also from what I am reading, for a newbie, I shouldn't be crawling around underneath for health reasons.
The good news is the rig is scheduled for a full service Monday. As the rig is new to me I am having everything checked, changed, inspected front to back. That was my plan regardless of maintenance records just so I know. Long winded way to ask what should I have the mechanic/technician look for? Or just soap the system and look for bubbles?
Glad I read the posts about not going under the coach, as I would have, being a newbie and all....Thanks.

RV2015,

First, if it takes all night to leak down it's not a massive leak. It could possible be the front ride height valves leaking. Mine used to do that also. On the front ride height valves there is a cover plate with 4 (if I remember right) torx head screws. Tighten those screws, once I did that I no longer have any leaks and the suspension stays up for weeks before it leaks down. You should also check all your line connections with a bubble solution.

Originally Posted by Skip426

Your problem , both tanks down to 55 psi. may indicate multiple problems.
On Freightliner the air suspension system is fed from only one tank.
If the shop isn't a Spartan facility you should try to round up an air system diagram for them to hand over when you arrive for the service .
Hope that the leak is something simple to repair, because any loss of air in the suspension; in less than a week anyway; can run the brake system short and reduce stopping power.
Going under the coach when the system is aired up to look for a leak, requires safety stands to protect yourself.

Skip426,

On a Spartan chassis your suspension air supply has no effect on your brake supply. Losing air on the suspension will not cause your brakes to under perform.

[RV2015]

I sent an e-mail to Spartan to see if an air diagram was available. Within 2 hours I had diagrams for the air brakes and the air suspension and a couple of trouble shooting tips, the first being check exhaust tube on the REAR height control, then check the two front control valves. Thank you Mr Fisher!!!! I am amazed by the service!
I did start the coach today and let the air build up to @120 psi per tank. Then just took a listen to see if I could hear an air leak...nothing. I measured the height ground to front fender and so far 4 hours in no change...I don't think it has magically been fixed. Real nice to know Spartan has our backs. I will post if/what the service center finds Monday. Thanks all!

[DAJO]

Originally Posted by RV2015

I sent an e-mail to Spartan to see if an air diagram was available. Within 2 hours I had diagrams for the air brakes and the air suspension and a couple of trouble shooting tips, the first being check exhaust tube on the REAR height control, then check the two front control valves. Thank you Mr Fisher!!!! I am amazed by the service!
I did start the coach today and let the air build up to @120 psi per tank. Then just took a listen to see if I could hear an air leak...nothing. I measured the height ground to front fender and so far 4 hours in no change...I don't think it has magically been fixed. Real nice to know Spartan has our backs. I will post if/what the service center finds Monday. Thanks all!

I had the same issue on my 2005 KSDP. It was the rear height control, about $80 from Spartan. The reason the front goes down first is that the front requires more pressure that the rear to lift rv up. Don't know why just told that by Chris at Spartan. Something about front bags being smaller. By checking the exhaust tube they are saying look for air escaping from the tube. My valve was leaking so bad I could hear it standing beside the MH.

[RV2015]

Originally Posted by DAJO

I had the same issue on my 2005 KSDP. It was the rear height control, about $80 from Spartan. The reason the front goes down first is that the front requires more pressure that the rear to lift rv up. Don't know why just told that by Chris at Spartan. Something about front bags being smaller. By checking the exhaust tube they are saying look for air escaping from the tube. My valve was leaking so bad I could hear it standing beside the MH.

Thanks for the info on the exhaust tube as I had some questions as to what I was looking for now I know!

[RV2015]

Just an update our coach has been at the truck shop going on 8 days. Not that I blame them, they are a truck shop so the coach gets sidelined often. No big deal, glad they are working on it, but would like to get it home.
As far as the air leaks the shop foreman called and said they do not think the air dryer filter had every been changed! So much for the seller and his we do all the maintenance as required statement.... Guess I was too trusting. So the air dryer is junk which has led to some of the delays. They could not find an original replacement dryer so the new dryer is bigger and they have to move it and re-plumb the air lines....I knew buying a used coach would have its pitfalls and $$$ issues but the purchase price was right so when all said and done all fluids and filters will have been changed front to back and a new air dryer. Now to start a maintenance folder for the coach. Next on the list, new tires before fall. No one said it would be easy (or cheap!)

[Algoma]

If your coach has the original airbags then it is probably time to change them anyway. Just like tires they may not look bad but after 15 years they could give way anytime. I had 2 on my previous coach fail after 10 years. I also changed all my height control valves. They are cheap insurance.
On the inflation pressure issue it is not true that the front airbags operate at a higher pressure than the rear ones. The front bags are smaller because they carry less weight. If properly designed both front and rear airbags will have around the same pressure at the max axle weights. The fronts go down quicker because they have less air to lose.
My '98 coach had a Bendix AD-9 air dryer which is still fitted to coaches today. I find it hard to believe the shop could not find a replacement for the original you have on yours.

[Ramets]

RV2015, while they have your coach, make sure they check your ball joint boots. If original I'll bet they're toast.

[JC2]

Originally Posted by Ramets

RV2015, while they have your coach, make sure they check your ball joint boots. If original I'll bet they're toast.

Agree and if you have the Spartan chassis, then figure $2500-3000 to R&R correctly and front-end realignment. We had it done last spring of 2014. Gotta love Spartan folks as they were supposedly lax in reporting this to their customers after they become aware of the less than optimal quality of the rubber boots covering the ball joints.

[RV2015]

Well got our coach back and the bill was, well lets just say double what I had expected. I am disappointed in the sellers song and dance and the maintenance records were pretty much bogus. But more disappointed in the fact I believed him, so the bad is on me. I should have know when the asking price was much lower then others. Oh well I now know exactly what I have and systems are all serviced and up to date.
They had ordered the exact air dryer and model the was original to the coach but it had been redesigned and would not fit in the original location as it is wider. It if had not been for all the labor to move the dryer, rusted/cracked lines and -plumbing the invoice would have been closer to what I expected. So valuable lesson learned maintenance log books are essential in a used purchase, I blame myself, but this coach will now have all records going forward. That air dryer filter will be getting changed every year from now on!
As far as the ball joints, the boots are gone but the ball joints are good. I found some post, on this site, of some making their own boots and a fellow that was using Boeing Shield T-9, which I have purchased. So will do some thinking on making my own boots, maybe VW transaxles boots from the 70s, or something on that order and try the Boeing product.

When I checked into having an inspection and the price was @$1200-$1500, hindsight now indicates that would may have been cheap compared to what I got into. Now whether an inspection would have found the air dryer fiasco I don't know.
So lesson learned, real live maintenance invoices or have an inspection of some sort even if it is a truck shop. We aren't upside down in this coach, so all is good, just disappointed we followed our hearts and not our minds...

[mikee409]

I stumbled across this post and could relate to the same overnight deflation issue.
I crawled under the RV yesterday after work with some soapy water in a squeeze bottle. Yes I did put jack stands under the chassis. I found the 2 front ride height valve covers leaking. Tightened the Torx screws and the leak stopped. The rear single ride height valve was not leaking. I checked all the air hose fittings I could find and found no more leaks. This morning the RV was still up to the height it was yesterday after I pressurized the system. Thanks for the help guy's Mikee