[tom]

The following free advice is worth every cent you paid for it.

The leans are common, and if the bus always leans the same way every time the specific part of the system the air leak is located is able to be identified. The leak in your case is going to be somewhere from the 5 port Norgren valve that controls that side of the coach back to the tag axle air bag. If you are lucky a few minutes with soapy water will show you the leak, it can be fixed and the problem solved.

But if that actually happens you should immediately run out and buy a lottery ticket.

Cold weather begins to show the effect of leaks faster than warmer weather. This is the time of year when coaches that were fine during the summer are going to start leaning or having air pressure start dropping faster than normal. You are now experiencing that.

If your proposed service provider is capable of explaiining to you where the leak is likely to be isolated, and he understands and can explain to you the difference between a five port Norgren valve and a ride height valve, and he can explain the purpose or function of each in your bus system, by all means bring the coach to him. But if he cannot do that you have to understand he will be vacuuming Benjamins out of your wallet while he receives on the job training.

Soapy water will never find all your leaks. Never ever. To find the leaks it takes a methodical approach which includes soapy water among other methods. If your air bags and valves are 10 years old or more you also need to recognize that it might be far more cost efficient to renew your suspension with new air bags and valves rather than play whack-a-mole chasing leaks on a system that is going to have them popping up from now on.

The answer to the question is a 5 port Norgren valve in your coach locks air into the suspension when the key is off, and when the key is on it is the gateway for air flow from the ride height valves to your air bags, or it becomes the flow path to add or exhaust air from the air bags for leveling. The ride height valve as the name implies controls the height of the coach when you are driving.

[Jerry]

Chip,

I have no knowledge of Commonwealth, but I can tell you that if they are not very experienced in the Prevost suspension, you could be in for a very long and expensive project chasing leaks and trying to diagnose the cause of your leans. If you can get to Jeff’s, your going to be way ahead.

[Chris]

the 98 will have push fittings– when you locate leak –replace with compression.. Bob

[Archived]

I would take it to Jeff’s! He is fixing air leaks on mine now. He knows what to look for.

[Larry & Diane]

Go to Jeff’s, it’s not that much farther. You’ll be glad you did.

[Sid]

Just an observation based on numerous comments on various forums over the last several years………

Depending on where the coach has spent its life, one area of leaks that has been mentioned numerous times has been the “ping” tanks, specifically corrosion under the band clamps. Once the tanks get rust in that area leaks begin to show up.

Bob did mention previously the push in air hose fittings. They have also been affected by age and that is why when we have the opportunity we try to swap them out for compression fittings.

[Rick]

Jerry,

Saw your bus in the air today, nice…… I really like the LED tail lights, I think Jeff is going to get info from you were you got them.

Al, you reading this?????

[glen]

Thanks for all the inputs. I’ll follow Jons advice and query the folks in Hopewell about their knowledge of the Norgren valves and Pneumatic systems of the XL. I appriciate the advice on the fittings as well.

If they (Hopewell) pass then I’ll bring the bus in. As for going to Jeff’s, if Hopewell does not pass the test I’ll see about heading west. Right now, snow is forcasted for the mountains and I-81 will be a mess. Hopewell has the advantage of location. I am time limited & it will be a factor. Work and full timing make it a bit more challenging hitting the road. Real retirement is 2.5 years off.

Quick question: Do any of youhave an average cost for replacement of the bags? If you had this done or are having it done, what is the amount you are paying or paid?

[Craig]

8-2013 had mine in for the dreaded leans for the third time. Prevost Houston said bags looked good but had replaced 3 ways and 5 way vavles and fitting on 2 previous trips in a year chasing leaks. Told them to replace them. They put 6 on and total was $3600 and change. They also put (2) R12 valves on same ticket and they were $112 a piece.

Got to looking and they replaced some of those up in Prevost Fort Worth about 9 months before. Still hits the ground on back end in about a week. Have ticket if you want to see it. Can scan.

[Davy]

Bags $147each from prevost.. R-14 $42each local. FWIW

[Jim]

air spring assembly— part #630104—-134.13 (6)—$804.78

air spring——————part#630259—–116.13 (2)—$232.26

R12 Valve—————–part#E10————614 (2) -$1228

3 way 2 pos.valve——-part#641274——-71.36 (1) —–71.36

Total for operation Code121–including labor———$3622.48 (job on 2-13-2013)

Another ticket Operation Code #121 (job on 12-26-2012)

valve, 3way 2 position.——-part#641274——$758 (1)—-$758

valve 3 way 2 position n.o.–part#641528–$188.57–(1)—$188.57

valve 5 way 3 position——-part#641531———$145.31—-$145.57

total for Operation including labor———————————-$1716.96

Have another one or two somewhere in file or in bus. These two were at Fort Worth Prevost. The other ones not shown at Houston Prevost. Heck on there website advertizing there opening my coach was on the left bay in picture. ust a heads up with what you could be looking at. Of course if they get it fixed okay. Mine still leaning after a few days. Gonna take mine down in the next week or two and get oil changed and maybe pee on it and check for leaks.LOL.

[Andy]

Glen gave a good summary of parts prices. Bob’s prices likely reflect the costs for your specific model year but they are all close enough you can get a fairly close idea of the dollars involved for parts.

Others may have a more precise estimate for labor because my numbers are based on the time I take to do things and I admit I putter around when I do the work such as scraping and repainting if I see rust or changing fittings, etc.

For air bags I allow myself 10 hours. For Norgren valves (3 five port, 5 three port) I allow 6 hours. I think your coach has IFS which means it has the small ping tanks at each air bag and I would allow some hours to change their fittings to compression plus examine them closely for leaks.

Without pulling up your pneumatic diagrams you may have a different mix and number of valves. My times and number of valves were based on my 97 solid axle coach.

Your best bet is to contact Jeff for a quote. In fact if you want a comparison between you nearby mechanic and Jeff ask them both for a quote. If your nearby mechanic cannot give you a quote without looking at the coach that will be your answer regarding his knowledge.

He’s more of that free advice……….Since you will be spending some dollars if you renew your suspension some of the labor involved is going to be related to getting access to the air bags and valves. That involves pulling some of the wheels and supporting the coach. That is a perfect time to consider going a little further and giving the underside a real close inspection along with replacement of other components which are now readily accessible. If your brake chambers have not been replaced recently give real serious thought to doing that. Have your air system checked and serviced. If there is any doubt as to condition, change out the protection valves, check valves and give consideration to replacing relay valves. Get the shoe and pad thicknesses checked. Look for cracks in the discs or drums. Look for hub seal leaks and only repair if necessary.

I know this will run into some dollars, but if you intend to keep your coach for a while the dollars you spend to keep the underside in perfect working order not only increases your safety, but it may prevent a towing charge or roadside repair that will literally cost half of what you will spend doing all described above. And once the above is completed you are going to have years of use of the coach without any need to deal with those items.

Others may disagree with my “scorched earth” approach to keeping the underside of the coach in tip top shape so it might be worthwhile to see if others have different susggestions.

[Larry & Diane]

Usually at 10 yrs is the point that airbags start to fail quickly. General statement. All rubber parts have a point in time when they are most likely to fail or become at risk. If you do bags –shocks easy to refresh at same time. Mileage is not the factor–time is the problem. General food for thought only! Prob on 98 this has been done… If not it’s time. Ch for cracking on Bags–also date of manfacture.

[joel]

I would do the same I just replaced air bags six back ones tag shocks and drive axle brake chambers it’s better to do now than later ,, Jeff’s is the place to go replace parts now and u won’t have to worry about it again for ten years my front bags had cracked a little back”s not bad. But did not know how old they are so I put new that way u know

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1999 XLV X-6872,  liberty #440

[glen]

On one of the other tickets chasing the air leaks had them replace all stocks and Ride height control vavles.When I bought my 1991 in had been sitting in climate controlled barn for 7 or 8 years with no maintenance . A little over 50,000 on coach. It looked new, like it had been in a time warp. I wanted all air systems to be checked and put back in new condition. I’m not complaining about price it’s what it is and just want anybody in it to be safe on the road.. Or as safe as they could be with me driving. As always, you folks have been a godsend on understanding this puppy.