PDA

View Full Version : Who do you recommend for air system service and repair?



Rufus Scout
06-08-2013, 05:59 PM
My 1985 Marathon gets the leans overnight, plus I have no idea of the service history on the bags or valves.

Thoughts? Thanks.

gmcbuffalo
06-08-2013, 08:25 PM
Rufus no better person than yourself. Search the POG articles and post for ways to diagnosis the problems. You need to replace the air bags and Norgren valves at a minimum. Since it is leaning it is most likely one of the rear bags. I remember one of the post saying to bring it up to ride height and lift the tag axle, if it doesn't lean your problem is in the drive axles bags. The other thing that would be a nice addition would be an air gauge on the auxillary tank. If you loose air in the auxillary system the tag axles will dump air and the rear will drop, When this happens to mine it general leans to the right more than the left. Look up these articles authored by Jon W and Hector, both very knowledgable on the air systems. If you take it somewhere without an idea of what is wrong they will spend hours and money chasing air leaks with no guarente of solving the problem, except spending a lot of money.

dale farley
06-08-2013, 10:41 PM
Rufus, As Greg said, you can do it yourself, and if you do, you'll save a lot of money. Even if you are not inclined to do it, you can learn valuable informaiton from this article, the video and by talking with Hector, Joe and others who have been through their air systems. http://forum.prevostownersgroup.com/content.php?52-Prevost-Suspension-How-Does-it-Work

Rufus Scout
06-09-2013, 08:22 AM
Thank you for your replies. I do understand how it all works, I just want someone competent and honorable (and experienced) to replace air bags, work on Norgren valves, etc.

i have zero interest in working on it myself. I rebuilt racing cars for years, even rebuilt a Ferrari V-12 motor successfully. My wrenching interests were long ago satisfied. Now I need someone EXPERIENCED, trustworthy and competent to do the work. Thanks.

Denny
06-09-2013, 09:38 AM
Contact Joe Camper, a POG member. Joe replaced all the air bags, valves, brake chambers, air hoses, etc on my previous bus. He is very good and very fair on the cost. You can send him a PM on this site or contact him at 708- 243-7871. Joe has worked on many POG members buses.

Rufus Scout
06-09-2013, 10:48 AM
Denny,

Thank you so much, that is the kind of info I am searching for.

Any other suggestions from the Group?

I should further say that my motorhome repair place COULD probably figure it out, but I want someone who already knows what they are doing without my having to pay for their learning curve.

Thanks in advance for suggestions.

truxton
06-09-2013, 11:33 AM
Hi Rufus,

Do not let someone try and figure something out on your Bus. I have owned far to many trucks with air systems and thought I new something. It's different.
Call Joe.

Later

bv

jetart
06-09-2013, 11:48 AM
I just had Joe C out to do a bunch of work on mine a couple of weeks ago (we did all the air bags, shocks, rubber brake lines, brake diaphragms, slack adjustments, adjusted the air valve linkages, etc, etc.....) In my opinion he is very experienced, and was willing to show me / explain how everything worked. Most important to me - he let me help as my wrenching interests are not quite satisfied - (hmmm V-12 Ferrari.....:).

Gil_J
06-09-2013, 08:33 PM
Your other option is Prevost. I guess Nashville is closest to you. I wouldn't hesitate to having them replace bags and valves, but I'd probably stop there. See if the obvious things fix the problem before thinking about having anyone troubleshoot the problem. It can be very costly with limited success unless the tech does this all the time. Chasing air leaks can be like finding the needle in the haystack.

Rufus Scout
06-10-2013, 06:48 AM
Anyone here have experience positive or negative with Prevost Nashville?

n33d2camp
06-10-2013, 07:47 AM
Yes, they do a great job.

dale farley
06-10-2013, 08:03 AM
Rufus,

There have been several posts about Prevost Nashville. Most were very satisfied, some felt the price was too high on some things, but from everything I've heard, I would feel very comfortable with them. You may also want to check with Russel Coach in Knoxville. There are many positive comments about them.

Gil_J
06-10-2013, 08:56 AM
As for pricing, give Prevost Nashville a call and ask for a quote for bags and valves. They may be a bit high but they know their product. I've used Prevost Ft Worth and Jacksonville and was satisified with both visits. I wouldn't expect anything different from Nashville.

Joe Camper
06-10-2013, 09:41 AM
Rufus Lets do some diagnosis right here so all can benefit .First U mentioned an 85. So is that the chassis or title? Reason I ask is that is a big trasition point for stuff. 84 was the first XL and 102 wide. The suspension components are not controlled by spool valves (norgren) and level low controls were 3 separate up and down buttons that very closley resembles air control buttons for an air seat. Is this what U have or do U have the 4 position selector with a singular up and down control button? Mine was an 84 chassis so im very farmilure with that pre norgren design they used simpler electric solonoids and diaphragm valves. Dalej had an 86 chassis and it DID have norgrens instead of the older diaphragm stuff. SOOOOOO how is yours controled that will answer that question. If your level low is 3 separate up and down buttons and is and/or 84 chassis U do not have any Norgrens anywhere on that bus. U have the leans. Any audible air leak noise?? Use what Greg suggested to start and tell us the results. But don't start at ride height. Try going all the way up both left and right rear. Wait, see if it goes down and note how fast and how much both sides rear. Then full up in the rear left and right THEN raise the tag up and wait. Again note the drop and how much both sides. Did this change the results or no? U also have a bus with emergency brakes drive axle only and manuall slack adjusters. When was the last time your brakes were adjusted and who did it? Im driving out to Middletown NY from Chicago in late July to work on a CC.

Joe Camper
06-10-2013, 11:11 AM
For the many who loose aux air thus causing the tag to raise and the back of the bus to squat after U have parked DO THIS if U found a pretty level site. Before turning the bus off raise the L and R rear ALL THE WAY UP in level low and THEN raise the tag. Often when the back comes back down its very close to ride height but the tag is already up. NOW when the aux air drops it don't change the height at the rear. If some minor adjustment to level left or right is still nessessary you still can but ONLY by bringing the high corner down. U can not go up in the rear with level low and the tag up . U can go down though 2 or 3 inches if needed to get perfect. I used to do that all the time and then Id drop the front about half down and the drains were all very happy too. BUT if U are loosing aux air shame on U what kind of a Prevo owner are U.:D

Gil_J
06-10-2013, 03:58 PM
Joe,

Great idea, if I understood you right. For sagging drive axle bags when the tag is raised you are saying to raise the rear of the coach before lifting the tag...genius!

Rufus Scout
06-11-2013, 01:57 PM
I do indeed have the Level Low system with three knobs and an on-off switch. Who knew? :cool:

I will perform the tests you suggest and report back. Thanks!

Joe Camper
06-12-2013, 07:20 AM
OK The way your bus is plumbed all those up and down buttons remain energized when U R in driving mode and need to be soaped up for air tightedness. U have no norgrens. Between the drive and tag there will be 3 way 2 position valves but they will be diaphram another potential leak point these will be the 2 biggest suspects besides air bags themselves.

Rufus Scout
06-25-2013, 10:43 AM
Now, because I'm a fairly new owner, here's something that might be of interest. When I say the bus gets the leans, I mean that it sort of settles when completely powered off. A couple of days ago, I plugged it into my brand new 50A receptacle at home and leveled the bus using the Level Low buttons. Two days later and plugged in it is still level. Why is that? Know that I have virtually no information on the Level Low function. Educate me, please. Thank you.

Joe Camper
06-25-2013, 12:57 PM
Do U have a auxilury air compressor and was it on when U plugged in? If so could be the auxilury air did not drop because of that. Was there a change in the weather 20 or 30 degree colder will affect the ability to keep pressure adversely could be that. When U left it did U leave the level low switch on when it normally is left in the "driving position" could be that. Could also be an intermittin problem. also something additionally I failed to note. U should be going over the entire bus with soapy water solution. If the bus is new to U and U have not done this yet why not. Its about 3 min. with a new bus and a spray bottle to find the first leak.

Rufus Scout
06-25-2013, 02:48 PM
I believe that there is an aux air compressor.

There is no on-off switch for it if there is one.

Yes as to temp change. 90 degrees day/70 degrees night.

Level Low switch was in "off" position.

Why haven't I gone with the soapy water test? Because I didn't know about it.

tradewinds
06-25-2013, 03:45 PM
Rufus, I know its a bit of a drive, but if you ever get to Florida we can do the work for you. If you need help please feel free to call we can help guide you through any issues you may run into. Tradewinds Coach & Marine (386)624 2833 or (386)785-4562

Joe Camper
06-26-2013, 09:06 AM
Take 2 shots of dish soap and insert into a almost full spray bottle of Windex and begin at the front and work your way back. The colder the weather the easier the leaks will be to find and stop. While on the subject would U like me to go over a pretrip air test like the DOT would do to a truck when safety inspecting it or R U already aware of that process.

Rufus Scout
06-26-2013, 09:14 PM
Yes Joe, thanks. That would be helpful.

BTW, the bus is leaning now after 3.5 days and when I start the engine, the two air gauges show empty, the tag axle alarm sounds, etc. until the engine builds up air on the gauges. So, no aux compressor, it seems.

Joe Camper
06-26-2013, 10:33 PM
OK so U need to tell us what the results of the things I mentioned U try was.

Joe Camper
06-26-2013, 11:55 PM
A pre trip air brake test. When U start the bus if it still has better than 100 psi that's good and is already indicating U R good on 1 of 3 things U will check here. Loss of general pressure, bus off, yellow button pulled up parking brakes applied. If its still 100 in the morn U have relatively little loss. That's good but in order to complete a pre-trip test U folks who resemble this IMO will need to drop pressure below 100psi to get the compressor running and then when the air dryer discharges idle down and turn the bus off at max pressure to really do it right. I have grown to get in the habit of doing this quick check as I roll in and stop because its way better for a bunch a reasons . U roll in and set the brakes. POP Ya get level last thing is ALWAYS turn bus off ONLY after the air dryer discharges and U R at max pressure. If something has begun to go south on me during the course of the day. Ya know one of those many things U will never here rollin along. Well, if there was, It will be much better dealing with it now rather than discovering it on a pre trip. but make no mistake this habit does not replace a pre-trip but enhances it. OK SO U got the bus at max pressure and the parking brakes R still set and U have shut the bus off. Time out 10 min. and note any loss of pressure during that time. According to the DOT if U have less than 10 lb pressure loss in 10 min. in this configuration is just fine to continue on. IMO that's nuts and U aint gonna catch this grease monkey lookin like that. Very unbecoming and especially for a prevo. anyway NEXT with the bus still off and the brakes set push the yellow button in and release the brakes be carful block it if need be and bus still off so u can listen good. At first the pressure will drop but only slightly and then it will hold. After it levels out look at the clock. Again it needs to be losing less than 1 pound per minute to be deemed safe according t DOT standards. Another opinion would be once U have ANY LOSS in this area seek it out IMIDIATLY and replace the maxi because that what it will be and I guarantee it aint to much longer for this world if it has started leaking ANY, ANY. This type of air loss is "emergency air" and is the kind of leak that among other things leads to dragging and hot and smelly brake and hub. FINALLY but not least the final step of the test . With the bus still off and the parking brakes still released now depress the brake pedal firmly and hold steady. Note any air loss or audible leaking U can hear. Should be NONE . If there is note what hub its coming from and repair it as soon as possible. This 3rd check is what is related to the "service air" in contrast to "emergency air" that we are checking in the 2nd step. That's it with a bit extra just for good. Do it when U dock that's the ticket it will help keep U ahead of the game

Rufus Scout
06-27-2013, 06:21 AM
OK so U need to tell us what the results of the things I mentioned U try was.
Huh? Please clarify. WHICH things! The long post about the DOT test? Or the soap test? Or? Thanks. I will surely do the DOT test this weekend, thanks.

Rufus Scout
06-27-2013, 06:22 AM
Also, what is the "Yellow Button"? Thanks.

Joe Camper
06-27-2013, 09:02 AM
Going back to pst 14 in this thread I asked this.
Rufus Lets do some diagnosis right here so all can benefit .First U mentioned an 85. So is that the chassis or title? Reason I ask is that is a big trasition point for stuff. 84 was the first XL and 102 wide. The suspension components are not controlled by spool valves (norgren) and level low controls were 3 separate up and down buttons that very closley resembles air control buttons for an air seat. Is this what U have or do U have the 4 position selector with a singular up and down control button? Mine was an 84 chassis so im very farmilure with that pre norgren design they used simpler electric solonoids and diaphragm valves. Dalej had an 86 chassis and it DID have norgrens instead of the older diaphragm stuff. SOOOOOO how is yours controled that will answer that question. If your level low is 3 separate up and down buttons and is and/or 84 chassis U do not have any Norgrens anywhere on that bus. U have the leans. Any audible air leak noise?? Use what Greg suggested to start and tell us the results. But don't start at ride height. Try going all the way up both left and right rear. Wait, see if it goes down and note how fast and how much both sides rear. Then full up in the rear left and right THEN raise the tag up and wait. Again note the drop and how much both sides. Did this change the results or no? U also have a bus with emergency brakes drive axle only and manual slack adjusters. When was the last time your brakes were adjusted and who did it? Im driving out to Middletown NY from Chicago in late July to work on a CC. The yellow button is the parking brake knob. Again, the DOT pre trip is a process everyone should preform every time the bus rolls.


Last edited by Joe Camper (http://forum.prevostownersgroup.com/posthistory.php?p=87240); 06-10-2013 at 09:54 AM.