TexasDrifters "Pneumatic Reliability Upgrade"

[dreamchasers]

Leak FREE! Yes, my coach is "Bubble Tight!

Those words are extremely rare in the Prevost community. But my coach, a 1994 model XL chassis, is leak free (both the braking system (Pri/Sec) and auxiliary air!). Now I know their are those "doubters", (you know who you are) that might doubt this, but it is true. I have had my coach on test for 5 days and have not lost one pound of air pressure in either system. For my coach, this is a first (during my ownership).

How did I do it! Simple! (All it takes is a little time and patience.......)

First, I used the nationally renowned "Texas Bubbler" as a leak detector and installed a "TexasDrifters Pneumatic Reliability Upgrade". This is a non - Prevost modification that included a 12 volt solenoid (I purchased the solenoid from www.airridefittings.com (http://www.airridefittings.com), a great supplier for air fitting and accessories) that blocks the air supply to the step well floor slide and ISRI seat when the key is turned off. These two converter installed items, IMO, are the two worst potential "leakers" on the coach. (You will need to locate a "switched" 12 volt (or 24 volt if you want to use that as a switched voltage) location in the Prevost electrical panel in front of the coach to control the solenoid). Attempting to get these two devices leak free will represent challenges that could mean continuous routine component maintenance and/or design changes, especially for the floor slide (as simple as the floor slide cylinder looks, if the shaft alignment is not perfect or is "floating", it will leak around the shaft seal when the slide is in the retracted position). I also found that my auxiliary air compressor was leaking back "through the compressor". So I installed a double check valve setup at the outlet to the converter installed aux compressor/inlet to converter installed air tank (not Prevost aux air tank). So after installing this modification and repairing a few minor leaks, 100% leak free.

A sidebar comment, I am one that thinks any modification to the Prevost suspension system requires much thought. I would probably do this only in an emergency, as a temporary fix. Remember, Prevost has a staff of design engineers developing things for durability and safety. I take a "hands off" approach to Prevost suspension modifications. Their systems works great and very long-lasting!

Many POG members may remember my comments at the Austin Rally, "That I "MANAGE" my air system leaks. What that means, I manage my leaks to a tolerable amount, then find and correct the leaks (the only leak free coach I have ever seen in when it is sitting in my bus barn). Once I take it out for a spin, all bets are off. So I am bragging now, while it last. Seriously, once your coach is tightened up, it should last a while, unless you have a component failure. The last time I did this level of air leak detection was three years ago. My aux air compressor was running twice a day, so it was time to check things out.

I call my coach "the other woman", because she is complicated and definitely a high maintenance gal. But when all systems are "fine tuned" and she is "tight (I mean air tight), she is ..........., she is ..........., well, the she is ....... "the other woman."

I'm happy!

Hector

[ajducote]

Hector,

That is GREAT! I have often wondered if the step slide was an issue. I think you have really got this whole air leak thing figured out!!!

[rfoster]

Good going Hector. Glad to see a CC guy thumping his chest amongst all those Buddy Brand buses.

And may I say you are truly an asset to the POG membership. Your efforts, experience, and attention to detail are appreciated.

Leak free is definitely worth bragging about.

[phorner]

Congratulations Hector!!

Attaining "leak-free" status is a tremendous accomplishment and you have every right to brag about it. I consider my bus as "leak-free enough" when I get the aux compressor to cycle only once or twice a day, but you have far surpassed my goals.

Isolating the step well cover and seat sounds like good advice.... I'll have to check that out.

Job well done!!

[Pete]

You and your coach are literally "FLOATING ON AIR". Way to go Hector! Keep that P/N handy, because I think that may be one of my trouble areas.

[jack14r]

Hector CONGRATS but we all know it is only temporary.

[BoaterAl]

My hat is off to you Hector and you can best be described as a man on a mission to the leak free zone. Post the message under your name...air leak free 12-07-2011.

You have earned bragging rights

[aggies09]

Jealous of the other woman. I am JEALOUS. Congratulations, I know that has to be a terrific feeling. I am afraid I will never know that feeling.

[Seabyrd]

Mine's next right Hector???
Good job !!
Wow !!

[truk4u]

Great job Hector! Isolating the step well slide is a good move, I just took the other route and decided to fix the leaking cylinder, but I won't do it again, I'm still sore in places I forgot about.

9078

[Jon Wehrenberg]

Great job Hector! Isolating the step well slide is a good move, I just took the other route and decided to fix the leaking cylinder, but I won't do it again, I'm still sore in places I forgot about.

9078

Must be catching because you are still a pain in my ass.

[Nolan]

Hi Hector
I still need to return the tool that somehow ended up on my coach when you helped me. I lost you mailing address to send back to you. Congrats on the "leak free" coach, but I am not surprised. You have it figured out.

email me your address and the tool is on the way. Thanks

[BrianE]

Good work Hector. After recently replacing all of the brake chambers, brake lines, and more to the point, airbags and Norgren valves, I've still got a serious leaner. I carefully checked each fitting and component after the job but obviously failed to get the system air tight. Since it's no worse than when I started, I will isolate the slide and seat after rechecking the entire system with Tom's electronic ears. What a simple and obvious (to you) fix for the most common leak sources. Thanks for sharing.

[Jon Wehrenberg]

Brian,

From your post it could be interpreted as suggesting aux system leaks are contributing to the leans.

Because of the number of relatively new owners I believe the following bears repeating:

IF THE BUS AUXILIARY AIR SYSTEM PRESSURE DROPS TO ZERO THE BUS SHOULD NOT LEAN OR SETTLE DOWN AS LONG AS THE KEY IS OFF AND ANY AUTOMATIC LEVELING SYSTEM THAT IS ACTIVE WITH THE KEY OFF IS DISABLED.. This applies to any coach built after 1994 or 1995 that does not relase suspension air if the pressure drops below about 35 PSI.

Once a coach is leveled, and the key is turned off, the air in the air bags is "locked" in by virtue of the 5 port Norgren valves blocking air from entering or leaving their respective air bags. If a coach leans or drops there is a leak either through the five port Norgren valve related to the specific position (left rear, right rear, or front) or in the air bags or fittings associated with that position. The rear suspensions (there are two, a left and a right) have an additional valve, a 3 port Norgren between the tag axle air bags and the drive axle air bags that also could leak to atmosphere.

[truk4u]

See, Jon called me a pain in the ass, but to really experience that function, all you have to do is ride in a vehicle with him as his cassette tape booms out "the best of the Lennon sisters."

[dreamchasers]

Brian,

If you take the time to look over the "presentation recording" that is posted on POG (see link below), it will take the mystery out of how the suspension system works. This is a presentation on "How Does the Prevost Suspension System Work". The presentation is stored on my Webex server and last about an hour. It is a live presentation with discussions concerning the Prevost suspension system. If you have never used Webex before, it will ask to download a small viewer software package. The presentation is the last in a series of seminars given during January of this year. Once you load up the seminar, you will see other POG member names participating in the seminar.


http://forum.prevostownersgroup.com/content.php?52-How-Does-The-Prevost-Suspension-Work

After click the link above, go to the presentation link at the bottom of the page.

Also, for a hand on guy like yourself, building and using the Texas Bubbler will take the guess work out of leak detecting. If you need more info, PM me and will setup a telephone chat.

Good Luck!

Hector

[phorner]

Must be catching because you are still a pain in my ass.

Now that was way harsh.....:cool:

[Jon Wehrenberg]

Paul,

Harsh, but true. All I get from him is abuse.

[garyde]

Way to go Hector. I'm sure it was a lot of work figuring it all out. Also, the belt tensioner, air bags under the A/C compressor, and the air bags under the generator can be a problem. On my coach, I also have the two slide out seals, air sliding doors, and a train horn!

[BrianE]

Jon, Hector, I knew that. Had a brain f***. Thanks for the wake up though and I'll review your forum Hector. Your bubbler is intriguing. Will give you a call if I don't find the leaks with my "ears".

[Seabyrd]

No 8 tracks?



See, Jon called me a pain in the ass, but to really experience that function, all you have to do is ride in a vehicle with him as his cassette tape booms out "the best of the Lennon sisters."

[Jon Wehrenberg]

Brian,

As you are aware I use my ears, a stethoscope, soapy water, my ultrasonic leak detector and finally the Tennessee Bubbler.

The bubbler never fails to find leaks, but is labor intensive and very time consuming. I use all other methods first because they are going to sort out the bigger leaks. But to achieve Hector's level of leak free the bubbler comes into play but unlike all other methods the only way to isolate leaks using the bubbler is to move progressively from fitting to fitting, device to device until you have identified and corrected all leaks. Using my coach as an example I have the bed lift and the dump valve actuators (2) on the same circuit. So I test the whole circuit and get bubbles. Then I have to go downstream to the next fitting and check again. I eventually will end up checking each circuit where it splits from the main supply and goes to each dump valve and the bed lift. Then whichever circuit shows leaks requires me to continue moving downstream until I am finally at the end device. Along the way I may have found 2 or three fittings (usually push in type) that had minor leaks and by the time I am at the end device or valve I may have cut the leak rate in half, but it still might leak 20 bubbles per minute at which point I have to decide if I am willing to replace a valve or if I am willing to accept that rate of leak.

I think Hector described having a leak free coach as obsessive, and I can say when you use the bubbler and know you have a leak you will want to deal with the leak. It must be like "crack".

Have fun.

[dreamchasers]

I think Hector described having a leak free coach as obsessive, and I can say when you use the bubbler and know you have a leak you will want to deal with the leak. It must be like "crack".....................................

I am stunned to think Jon views my work as obsessive. Some people polish slack adjusters, other have a leak free coach. Which one would a coach owner want?

Hector

[Pete]

LEAK FREE!

[BrianE]

Hector, WAY TO GO!!!

[charlesebrownjr]

You know, of all the tihings I have to take care of on my bus, I don't have any "COPPER PIPES" to polish. Really makes me feal left out or maybe I own an inferior coach with nothing but plastic pipes !!!!!!!!!!!!!!!!!!!!!!!!

[Jon Wehrenberg]

You know, of all the tihings I have to take care of on my bus, I don't have any "COPPER PIPES" to polish. Really makes me feal left out or maybe I own an inferior coach with nothing but plastic pipes !!!!!!!!!!!!!!!!!!!!!!!!

I have my people handle the details relating to polishing slack adjusters and copper pipes. Right now they are working to get a shine on the brass fittings going into the Norgren valves, and putting a little tire dressing on the air bags to make them look spiffy.

You cannot see my air leaks, but you can see the attention to detail on the mechanical side of my bus. The Liberty motto is "Put your Money Where It Shows". The CC motto is "Make it Leak Free"

Marathon has Kevin who is so fastidious about his coach that rumor has it he has a crew proceed ahead of the coach to wash and vacuum the highway so he does not get dust on his brake chambers.

[charlesebrownjr]

Jon, I must say your last post was well worth my $100.00 membership fee. It's laughs like this that keep me checking the siite at least twice a day. Merry Christmas to all. :-)

[Jon Wehrenberg]

Buddy,

I wasn't joking. Every word is true.

[BoaterAl]

I saw Kevin's bus at POG X. Impressive and over the top in clean. Makes us Marathon owners proud.

I need to get after my copper pipes as there is not much to do on a Marathon.

[Woody]

GOOD TO HAVE YOU BACK JON!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[hhoppe]

Lazy Floor Slide: Any clues on why my floor slide all of a sudden got slow on extend and retract. Remedy Please??

[JIM CHALOUPKA]

Check to be sure your air pressure in the aux system is where it is supposed to be.
If you can get to the supply line going directly to the floor slide, put in a small amount of air tool oil and work the slide in and out several times, Liberty did this on my bathroom doors and they now open and close without shuddering.

JIM

[rahangman]

have thought about doing the air tool oil on my air/operated windshield wipers that seem hesitant/intermittent. That said, recent trip to OysterFest with a LOT of rain, the wipers got a good workout and seem to be better now, but still could improve. I use a small 12v pump for the washer system instead of the antiquainted air for the washers and get plenty of water/solution on the ws now.

[HarborBus]

It's probably just getting old and slow like the rest of us.........................

[rahangman]

Thats probably it, Elliott, although at least it doesn't just work and moan and complain, like I do....

[charlesebrownjr]

Hector, do you work on the air systems on LIBERTY'S :-)) Just asking, don't have anyone particular in mind.

[dreamchasers]

Charlesebrownjr,

I have not looked at a Liberty Coach, yet. But I am concerned about the glare from all the polished brass and slack adjusters. I think I would need to wear a welding helmet to protect my eyes.

Hector