View Full Version : Air bag air tanks

Joe Camper
11-20-2013, 10:04 AM
Around 99 or so prevo added small seporate football sized air tanks 8 of them 1 for each of the 8 air bags. It has been increasingly obvious to me as these buses age these tanks will begin to add another complexity to the leans and stopping them. I did work on a 99 chassis yesterday and found a weld on a seam leaking. I have also previously replaced 2 others that rusted thru. I also see many rusted bad on buses with low miles mostly stored inside. Can't correct a lean? CHECK THOSE TANKS and not just the fittings spray the entire tank down just like the rubber parts of the bag when looking for leaks.

dale farley
11-20-2013, 12:23 PM
Joe, I wasn't aware of the addition of the tanks. Good to know.

Joe Camper
11-20-2013, 12:40 PM
These tanks r attatched to IMO brackets that r also usually very rusty and deterioating. Attatched with 2 hose clamps that allows moisture to develop and remain between the two. When looking with soapy water get that point where tank meets bracket good and wet.

11-20-2013, 11:04 PM
Hi Joe. I have not heard this before. good one.

dale farley
11-20-2013, 11:18 PM
Joe, Do you see anything an owner can do to extend the life of the tanks?

Joe Camper
11-20-2013, 11:24 PM
I did a XLII in Virginia an entertainer that saw many many miles in all weather. It was the first bus I ran across with the leans due to a leak in one of those tanks. It was obviously rusted thru. But it got me looking in that direction as I continued on to other work. What im seeing is another component that is going to create another element in fixing leaks in the suspension. The tank I found with the pinhole at a weld of a seam this week has some yellow spray on it and if I had to guess id say, might be a replacement itself. Its not rusty like the others are and its got that yellow spray and some white hand scratched letters looks newer. Bad Weld? Possibly that too. Ever crawl under your PU and marvel at how some components show no sign of corrosion while other pieces R rusting away. The bumper brackets on my Ram did that bad. Rest of the stuff looks mint. Those pieces had to come from another source Some of the things on the bus r the same. IMO these tanks and brackets fit that description.

Joe Camper
11-20-2013, 11:49 PM
Sure Dale A guy could remove them and paint them and the brackets with Pour 30 or some such product they r not to hard to get out. I wonder if Kevin Erion has rusty bag tanks???:) Another thing Im seeing more and more of and that's chassis that came with push in air fittings that are now gone for the old compression ring type. That was one of my signatures but now many chassis R getting straight. Any time U R planning to remove any suspension fitting assume it will not work as well the second time around. If U like the push in fittings and want new replacements that's AOK they do work well new. And by the same token do not assume the old compression ring type will be forever either. If U find U R cranking down noticeably greater that other connections with an old compression ring style that fitting is junk get it out of there. If U have an H or an XLII U can look directly at the front drive bag the 3/4 plastic line (massive) between it and its air tank. The fitting out the bag is old style the one going into the tank is push-in and that's a factory design why I do not know. It can be taken apart and put back together with similar fittings on both ends. I have done enough retro fits to old style fittings I can put togeather a complete set of new brass for bags norgrens and ride height valves from memory. If anyone is doing this call me I will get U almost every fitting u need in advance. ALL years R not the same. Plastic lines to the air bags range from 3/8 5/8 3/4in.

12-07-2013, 09:42 PM
Good tip Joe, mine has obtained the leans since cooler weather came. Are all the Norgrens that may cause a lean, located above the driver side rear axle behind the fender? On an H?

Joe Camper
12-07-2013, 10:39 PM
Jerry did U notice the accelerated corrosion forming on your air bellows bracket in relation to things around it? Well that's the same kind of thing Im seeing on the air bag tanks and brackets. IMO these R all prime candidates for powder coat.

Even on that H with the removeable fenders the tank for the front bag for the drive axle has a fitting on it that U can not get to unless U r completely up and under it. It is a Thru T 1/2in pipe to 3/8 plastic and its a push in and it is sticking right out the middle of the back of the tank .

Pulling these tanks, painting them, replacing the push in fittings, its all a good project if U R looking to stay buisy Id give it about a 5 in difficulty.

Yes on the drivers right norgren controls. On the passenger side they have been moved to the middle for the house batteries. Depending on what slides U have may also have required slight differences for location drivers side.

Not just looking for leaking fittings.

Your 2 position norgren will be upside down be sure to put some soap on the short tail sticking up. Also where the ends meet the body of the valve there r very tiny weep holes barley see them spray there. Might bubble. Also spray heavily on the backside of the norgren valve body where it buts up against the frame case the backside weep hole is leaking Ive encountered that too. Wait be patient use the best leak detector U can find. An overnight lean can be a result of a very tiny leak. Little bitty bubbles very slowly forming will make her roll over. IMO I would not disrupt the drains on any of the air bag tanks if they r not leaking or U do not have replacements in hand. I never get anything out of them U r looking for trouble if they don't currently bubble and U crack them open. Spray the exhaust tail for the ride height valve the 3way norgren at that corner could fail in a way that would send air out there too. That should give U some ammo.

12-08-2013, 09:58 AM
Thanks Joe, lots of stuff to check. So the pass side valves are moved because of the house batteries, so where and how do you get to those? I have 5 Norgrens on the driver side , so does that mean there are 5 of those on the other side too?

Joe Camper
12-08-2013, 11:17 AM
Well if U have 5 on the drivers side Id guess they moved the passenger side over there. There R 3 on each side for controlling suspension and tag lift. Unless U can see others mounted in the middle framing members that's were the pass side was moved on your conversion. R all of them norgren or r their a couple that look like a different make?? U will need to follow the 3/8 plastic to identify what is what.

If they did move them there instead of up in the middle IMO that would be a better spot to have moved them. Every now and then I will find a norgren or 2 that the converter used for controlling some house stuff but not too often make sure that is not what your looking at.

For your suspension each side should have 1 larger 3 position norgren and and EITHER 2 smaller 2 position norgren OR 1 2 position norgren and 1 similar to the 2 position norgren but another manufacturer.

The second smaller 2 position valve weather a norgren or not is for the tag lift chamber and is NEVER a factor in the leans. Only time its energized is when the tag is raised. Its short tail or exhaust port is where the tag air bag empties out through when its being lifted.

Joe Camper
12-08-2013, 11:21 AM
If not converter installed controls Id guess they moved the 2 for the suspension pass to drivers side and left the 1 smaller 2 position for the pass tag lift where is originally was on the pass side. That could be why U r looking at 5.

2 larger 3 position and 3 smaller 2 position.

12-08-2013, 01:10 PM
I had to replace a air tank rusted a pin hole through on the bottom by the weld on my aux air tank and its not subject to outside weather I would suspect climate change and condensation working from the inside out all the paint and powder coat in the world won't help that ? maybe switch to aluminum or stainless tanks ? When that happened my wobble pump or dry air pump ran away and burned up I bought a industrial pump and mounted a Boat bilge fan at the end to the new plate I made to mount the motor now the fan kicks on and air cools the pump to help extend the life any air pump that does not use oil depends on air to cool it and when we put it a compartment it helps air move across the fins to cool the motor to extend the life,
Chesterton makes a product called heavy duty rust guard the amusement parks spray allot of there stuff to keep from rusting and I believe it is paintable after that the DOT also uses it,

12-08-2013, 01:14 PM
Here is the link I am not a Chesterton Distributor I just know about there products as my wife sold them for over 20yrs and is now retired you would have to contact an authorized dealer in your area here is a link for the product its a winner.


12-08-2013, 01:46 PM
I would like to see a rusted tank removed and cut in half to investigate the rust pattern ?

Joe Camper
12-08-2013, 03:58 PM
I would too. I might be able to make that happen. Larry the pinhole I encountered was not at the bottom it was in the middle of an end. I love to guess and would say cutting one open would reveal little or no rust. I think 1 time I got the slightest of a spit of anything Ive ever cracked open to drain.

I didn't open the link? was it product to paint the inside? That would not be too difficult to do that. I don't think its the paint. Aluminum tanks sure would add to the "stuff" be bragging rights for sure.

A cooling fan on the aux compressor is a great idea ive never seen that before that makes it even better IMO .

Aux compressor setups R all over the board another great HUGE topic. Much room for improvement.

I have a H right now Im going to change all that. Get the chincy small dc powered aux compressor stuck in completely wrong spot and get it right this time. (This is a beautiful black Vantare that is pretty much a perfect conversion in every aspect ). We should look to the entertainer industry they do it better I think. bigger compressors with tanks. Dennys old CC had a similar set it was behind the front bumper. Some of us but not many have optimum components and design.

What would be the downside to completely separate the house from the chassis ??

Many of us have DAYTON a/c powered. Most R 1 cyl a small few R 2 cyl. All can be had at Granger. Many older CC have d/c Thomas that IMO R just about worthless Im not a big fan of ANY d/c powered and oilless even less.

I know space is tight but the converters really do a good job putting these components (stuff) in difficult places.

If I was the builder A decent sized a/c powered with a crankcase that holds oil and its own air tank. I would run it off an inverter circuit. It would not interface with the chassis. There would be a water separator and the water purge would be on a adjustable timer sneezing once every 12 hr or whatever.

This was on a Superior conversion I got to work on entertainer stuff . Best setup I saw so far. Entertainers also can turn the air off to pocket doors enabling them to work like a simple pocket door in case of emergency. And the button is right there next to the open and close buttons. Not buried in a remote location that U find 6 mo after buying the bus. That would be a option I would enjoy if I had a camper with air pocket doors.

12-08-2013, 05:10 PM
Joe, I think Vantare moved all the valves to the drivers side, which is good. Found more leaks today, making progress though. Before my aux compressor ran most of the time, now at least it's cycling .12538

Joe Camper
12-09-2013, 11:24 AM
OK that photo is the front bag, tank, and ride height valve on the drive axle passenger side. Your tank looks not too bad but very similar to the one I just repaired with a pinhole.

Couple things here. First check out the MASSIVE 3/4 plastic air line between the tank and where it goes gown and into the top of the airbag. NOT NORMAL this is tool time stuff VERY BIG. Another odd thing I would like a engineer to explain not in the photo. The corresponding rear bag for that same axle and corner is fed thru a 5/8 plastic line very different. Don't understand that but is also of note for those who intend to do "stuff" in that area. Might help in prepping for a project.

All the pipe out of the tanks and bags R 1/2 in pipe. The tanks have 1/2 by 3/8 reducers in them then the fittings R 3/8 pipe to 3/8 plastic.

ALSO look at the combination of the push in fitting in the tank and the compression ring style on the bag. It is pretty simple to change that push in to a compression ring if U want. Ya gotta shorten the plastic by about an inch and then it goes togeather before the tank straps get snugged up thats all. That push in is a 1/2 pipe by 3/4 plastic 90. If U intend to disrupt that be sure to have a new something in hand.

Another thing in there U can not see and is important when U cant find a leak U R looking for. Sticking out the middle of the back of the air tank there is a thru T or U may call it a branch T in any event for U guys with the removable fender wheel skirts if U really stretch U can get your hand back there and Just feel it. No way to soap it and check it without getting under and up in the bowels of the rear suspension. It is also a Push in fitting. On install U have enough plastic line to insert it into the push in and then move the tank into position and clamp it down. I do not like that because when U move the plastic around by moving the tank around what is not A leak when U insert could result in a leak after u move the tank in and mount it down. These fittings need to be old style compression.

Nother thing in the photo is the ride height valve. For U guys with Pre around 98 this is what the new ones look like. When adjusting ride height I find it easier to loosen it at its lower mounting screw and move the bottom either to or away from U. The bottom hole is purposely slotted for this purpose. Also because of that slotted bottom hole before U replace 1 get a good look at its spot before loosening it up for replacement. The other adjustment on adjusting the length of the rod is a PITA.

Theres some fuel for all U grease monkeys out there.

Joe Camper
12-09-2013, 11:30 AM
Keep going Jerry U R on a roll. This is the best time to chase leaks when its cold they R more evident.

12-09-2013, 02:20 PM
A Little story, when I was in the Printing Business we bought a $10,000,000 three story web press it was top of the line and almost everything was pneumatic about a year after running it our electric bill from our massive air dryer and industrial compressor on the other end of the plant was outrageous, when you stood inside the press you could here hissing coming from just about everywhere,
We started the long process of changing to compression fittings instead of the push in quick connects and gave the compressor a rest and dropped our electric bill, the thing here is our compressor could still keep up and are back up compressor would fire off once and awhile, in a bus eventually your compressor won't be able to keep up especially on those cold nights when the air leaks really rear there dirty heads, Compression fittings are Usually a one time fix you can also fix the push in model usually by just cutting a short piece off the line but it I like to address problems once if possible , I found all my push in connections on my generator air bags were leaking like a crazy so I replaced all with compression fittings,

12-09-2013, 02:23 PM
Another thing if you spray the push in fittings and they look good wiggle the air line just a little you might be surprised,

12-09-2013, 07:44 PM
The more I fix, the more leaks I find. I am changing everything to compression as I go. What a process!

12-09-2013, 07:48 PM
Larry, you are exactly right on wiggling the fittings. Also, I have found that if you air up the coach with shop air to 125 lbs. It will show the leaks better.

Joe Camper
12-09-2013, 10:18 PM
Also there is a lot of crap on the market get good stuff, to add to your stuff:p


Look at this these R both 3/8 plastic compression from different manufacturers. Bottom fitting piece of crap don't use this stuff. Both the nut and compression ring r half the size.


Here is 2 3/8 T both of them. Get the picture.


Also if U ever encounter copper inserts instead of steel don't use this "stuff" either. Both types in the photo.

Joe Camper
12-09-2013, 10:32 PM
If U want a source for the "good stuff" call Precision Hose in Lansing Ill. Its the right stuff at the right price even after shipping they r the best Ive found. I have wasted countless hrs out of town chasing stuff down and finding crap now I order everything I need from them they overnight it to me if I want. Tell them I referred U or its for me they will wack the invoice generously.

Joe Camper
12-09-2013, 10:52 PM
Now U got me cleaning up my tray

Look at these 2 Ts the one on the left is a street T with pipe compression ends goingL and R


The other T on the right is a branch T pipe out the bottom like the other but compression has 1 going up 1 going 90. There is also a thru T for ganging things togeather don't see that much. Last a bare one to assemble a fitting from multiple components, see this all to frequently. This happens from compromise when the correct 1 piece is elusive.

Joe Camper
12-09-2013, 11:03 PM
Here is the fitting that is not visible or even soapable from just looking in that is coming out the back of the tank for the front bag on the drives.


U R looking at a 1/2 by 3/8 pipe reducer AND a 3/8 Pipe to 3/8 compression branch T, Push in type. NOT the good stuff, piece of U know what.:eek:

Joe Camper
12-09-2013, 11:05 PM
AND when U replace it U can get it done in 1 piece without needing the reducer right? That's right Mr bus driver

12-10-2013, 11:32 PM
Joe, the good fittings with the "built in" thread sealer, is that enough sealer, or do you add more? I continue to add Pipe sealant even though they have pre applied sealant. Just wasn't sure how good the pink sealer is.

Joe Camper
12-11-2013, 12:18 AM
I add thread tape. Its ok with spool valves keep it off the first thread and stretch it on in the right direction not backwards. I have learned that sometimes seems like the red thread stuff on the fitting wants to mar the aluminum threads on the 3/8 ports on the norgren. IMO it all too often makes that last revolution to tight very difficult and overtight.

Any time I go to thread a fitting into a norgren and it begins to get tight too quickly or rough I stop and I grind off the red stuff and just use a liberal amount of Teflon tape on the bare threads. Always seems to feel better afterwards. Easier to point the fitting where U want it without it being either too loose or too tight.

Want bling cast a clear valve body for the norgrens. Id like to see that. easily categorized very cool "stuff"

While sorting fittings today and spending money on more (MPD) I came up with a good idea for all the old push in fittings I have removed off of every ones buses. I got a bucket full ofthem. Im going to polish them make a sculpture and sell it for charity at the next rally. Ya know give someone a chance to buy back the fittings they threw away.

Jerry I don't care for that red stuff The norgrens do not like it that's for sure.. I always go over it with Teflon tape unless as described above. Pipe dope is just as good if not better but something is always in order IMO

Joe Camper
12-11-2013, 12:27 AM
Parker fittings that is what I buy. I don't care for their brake hoses rather use aeroquip ends on those. They make good fittings. If U use Precision hose ask for Tom I told him some bus guys might call. The bag of fittings I walked out with today would have cost me almost double anywhere else. Hope they never realize Ive never been able to find anywhere else. :p

12-11-2013, 10:01 PM
On my third air filter water trap replacement they were all leaking out the bottom one is an auto drain, I was going to just replace the parts inside but all the plastic just disintegrated so I just ordered new 2 small and one large so far from grainger,
Auxiliary pumps still kicking on and not shutting off So I will be back to the engine compartment to check all the bags and connections, air floor slide seemed to be good, If it would warm up about 30 degrees it would be fine I think :)
The Wife will not let me under the bus at all Wish I had my own pit handy :confused:

Joe Camper
12-19-2013, 03:57 PM
Lets revive this thread. I went back out to the bus with the pinhole in the drive bag tank drivers side. Took the repair to the pass side a step further


Take a look at this photo of the front drive bag tank with its push in 1/2 pipe by 3/4 plastic 90 degree fitting. The 3/4plastic line is very short 6 in and its not lined up that puts that plastic line in a bind with the fitting not what U R looking for with a push in at all.

U can not slide the tank over to line it up for the slot in the bracket to facilitate the threaded plug for the drain.

Joe Camper
12-19-2013, 04:09 PM
Here is what I came armed with. Any of these combinations will work U would think the bottom left would be the choice for the 1 piece issue but I decided not. It was too crooked coming up from the bag and so close to it.
hat I think was the best solution. I was able to use an exact length nipple this way.


Now its lined up and has 2good compression ring fittings.


Joe Camper
12-19-2013, 04:17 PM
Here is the backside of the tank with the new fitting on the left that u can not see just by looking in with the skirt off or up .


U need to pull just the outer tire and rim drive axle and the flap and is a cinch to tighten after the tank gets clamped down.

Had to do a bunch of in and out and experimenting to get it to where I thought it was right. All that needs done now is pull it 1 last time to paint it. I hope Im explaining the little details often possibly overlooked. Comments welcome.

Joe Camper
12-19-2013, 04:30 PM

SEE THIS !@#$ I understand the importance of draining the tanks from moisture or at least the ability to check them.

Do U understand the importance of having suspension air airtightedness that's a joeism:p

Well if I ever get a chassis with the football tanks (another joeism) mine will have nice shiny 1/2 in brass pipe plugs. If U feel the urge to check them pull the plug check and replace the plug. U can dump the air with a plug by using the level low or a dump switch. After U go thru this routine 5 or 6 times without ever encountering any moisture in them U will satisfy that curiosity.

All these things R is a leak waiting to happen. Get rid of these on the bag tanks and go to plugs. make the plug your drain. If U have these I would suggest U do not EVER open any of these unless U have new replacements in hand either that or plugs.

Joe Camper
12-19-2013, 04:38 PM

Here is 1 last photo of the bracket for the newer style ride height valve (came in around 99 chassis). It is looking in from the front and if u look real close u can see the slot just a smidge look close at the bottom nut. This is slotted to adjust ride height valve. Bottom hole is slotted top hole is not loosen just enough to move the bottom either to u bus goes down or bottom away from u bus goes up.

The ride height valve uses fittings that r 1/4 male pipe to 3/8 plastic compression

Joe Camper
12-19-2013, 04:57 PM
I cant seem to get any rhyme or reason to where they used push in fittings and where they didn't. Cooky Canadians:rolleyes:

Joe Camper
12-19-2013, 05:10 PM
Why R some of my pictures first showing up as actual photographs then after going back to the thread come to find some of them turn into the attachment word that U have to click on to open instead. I don't get it. I don't know what Im doing. Help me:( Im doing my best to post some stuff that is really something of value this is not good these attatched photos

12-19-2013, 10:14 PM
Great info Joe!

12-20-2013, 07:26 AM
Joe, It sure seems like you would be a candidate for one of our Rally Seminars.

Joe Camper
12-20-2013, 09:33 AM
I still do not have a bus but Id be happy to take someone else's apart as instruction.

We should have a Mini rally that is a workshop seminar fix a few of your issues give u a chance to get your hands dirty and pick up a few things other than adult beverages and bad jokes.

Im going to be in Tampa on the 13 and 14th for Jamie's show and looking forward to meeting as many people as I can when Im there. Will U B there? Im coming down in my service truck and be in Fla for at least through the end of February.

Im camping a 62 GM conversion I might just keep. Its a 8v 71 with a V-drive with a 5 speed stick.

Very nice conversion I was floored when I first saw it. Not a professional conversion but had to be someone in the industry did it for themselves.

Seminars R fine but lets do a workshop and actually fix some "stuff"

Joe Camper
12-20-2013, 11:05 AM
What year did this equipment appear? Im sure 99 chassis have them and also sure 97 did not.

Who out there with a 98 chassis both H and XL im looking for, Let us know what stuff is on yours so we know.

I can also tell U prior to this change the suspension was in a constant state of evolution many frequent small changes from year to year.

Since then there were very few changes at all. When they went to disc brakes on all 3 axles (year unknown 00 01??) and went to 5/8 and 3/4 plastic air line going to the air bags along with the football tanks (footballs:p) back there in 99 or poss late 98 that's still what the stuff is today.

12-20-2013, 02:21 PM
Dear Joe, I am greatly enjoying your near encyclopedic knowledge. I have tasked our 35 year old son to read your stuff and commit it to memory. I am slowly doing preventive maintenance on our RV. After we replace the radiator and some hoses (after Christmas) our next job will be the air system. I now plan on following your suggestions on the valves, air tanks, fittings, and bags. We have a very slow leak somewhere but I want to have an RV that comes close to being completely reliable as possible.

If you ever come through eastern North Carolina along I95 or anywhere near Pinehurst you have a place to stay. We promise to feed you, house you, entertain you, and only then pick your brain.....


Joe Camper
12-20-2013, 05:14 PM
Otto Im trying my best in these threads to help u help yourself if u have the ability to do it.

U have a great year rivets first year of the 6 speed and no footballs. I will promise to stop if U do the same should U get through Chicago.

Joe Camper
12-20-2013, 05:25 PM
Otto what disc brakes R on yours Rockwell? DO U know?

12-20-2013, 10:51 PM
This spring we had some problems going down the long steep mountain on I-40 at Black Mountain North Carolina. As soon as I got home that day I had the brakes checked by the best truck/bus mechanic in our area(who happens also to be a very good friend). It turns out we went down the mountain with ONE operating set of brakes!! We were fortunate not to have a complete failure or fire. The replacement parts came directly from Prevost in Chicago. The parts people in Chicago were great at detective work. Our RV is very unusual. It was built by Prevost as a prototype handicap RV. Recently I finally received from Prevost the original paperwork on the renovations. The brake parts we used were Rockwell and the original paperwork from Prevost show Rockwell. The basic vehicle is a 1996 model with renovations in 2003 and more renovations in 2006.

The two times I have called Prevost for parts or information on anything about this vehicle have been complicated. Since the vehicle was a prototype the VIN # seems to confuse them. A number of renovations were done to the vehicle while it was being renovated into a handicap RV and those renovations always confuse the parts people. As an example the front cap is much newer than what the VIN# says it should be. Also the converter in Canada used by Prevost is a mystery. No one in Ste-Claire can remember who did the custom work. The conversion work was done well but I've had to wing it sometimes in trying to figure out the design. All in all, it has been a wonderful, but steep, learning curve especially since this is the very first RV we have ever owned.

My wife loves the thing since it is the only way she can travel. My goal is to make this vehicle as reliable as possible since being stranded in the middle of nowhere with a wife in an electric wheelchair on the side of the road is not exactly fun.


12-20-2013, 11:07 PM
I have been chasing air leaks for quite awhile, I have fixed and replaced everything I could find, I was stumped ?
Well I have always worked on all my own equipment cars truck build motorcycle motors etc etc,
Well when we bought our Bus my wife was so happy but she said I could work on anything except she made me promise not to do any work underneath the bus, So out of frustration I ran the bags all the way up and gave them a spray didn't see anything so I slid in behind the passenger side tag under the mud flap there is another little flat that runs across the bus I slid under that and saw a tank hanging straight down with a blue push hose attachment on the side and a water drain on the bottom I squirted it and it was blowing Like a bubble machine a very bad leak,out of both the hose and the drain, Such a simple fix for me wish I had a pit !!!!!! probably more of the same If I could have a pit for a day, I can not believe no one in this town has a pit in there shop, But I know when I drop my bus all the way down I can almost pinch your toe under my front bumper, So I just gave a couple squirts and slid out, So I am at a stand still right now ??? Love your posts !!!

dale farley
12-20-2013, 11:34 PM

This is what I built and used before I installed my pit. They work under the front or rear. They take a few sheets of plywood, glue and screws or nails.

12-21-2013, 12:39 AM
I'm still working on air leaks. I've replaced all 5 Norgrens with compression fittings, none of those are leaking. I took the line loose from the norgren going to the bags, and pressure tested them with a gauge and a valve stem to put air in.1260212603
The starboard side leaks 3 lbs per hour. The Port side leaks 10 lbs per hour. The front doesn't leak or sag.
So I am continuing with checking leaks. Going to put it on ramps this weekend.

Joe Camper
12-21-2013, 08:06 AM
My number is on my home page do not hesitate go call anytime u run up to a hurtle u need help jumping

Joe Camper
12-21-2013, 09:42 AM
Larry that inboard football is for your rear bag on the drive axle. the tag football is hanging outside the frame rail and the other one is in front of the plastic drive fender.

Im in the process of building another few sets of stands. U H guys R very different at the body support points in the rear. The stands that work great for the xl do not work for U. There is a piece of 2in square stock going left to right at that support point that necessitates a 2 in notch to be incorporated into the stand. That necessitates using 1/4 in wall 4in square stock instead of 1/8in. ALSO often converters welded flat washers for hangers for a very lower flap and that last washer on the end will need to be removed and repositioned a few inches in.

I also thought about putting a perfect fitting, solid, square plug into the end of that piece and then just using shorter stands. Again this is H STUFF U poor guys:p Ill show when I get that thread going and let u decide.

Im going to do an entire thread on stands for both the H and the XL im going back to OK after Christmas to do work on both and both guys have asked for sets.

Getting IFS off the jack and onto a stand takes a bit of thought with really only 1 point to do it Ill show my tricks there so u do that safe and don't damage anything. Tag too same scenario.

I am going to continue to pass on every little snit of info I learn by working on all your buses and put it right here.

Jerry cool tool it needs a spot in the tool box drawer marked 'stuff" Seriously what U r doing there is no different than a large percentage of big rigs that have suspension air gauges in the dash but for a bunch of different and additional reasons than us for wanting this. Trucks unlike us R constantly very differing weights they go from 30,000 empty to 80000 loaded on a daily basis. once a driver learns his gauge he can begin to calibrate psi into weight. For example usually about 60 psi on the suspension gauge is right around 34000 on the drive tandems. They r just like on board scales. If U were loading a dump with fill out in the boonies U can get a full load and not be too heavy either very convenient for a gravel buggy.

Our buses being a constant weight do not benefit from that aspect. Jerry U could very easily go straight up thru the floor with an air line and put that gauge right in the wall at the head of the bed just so every time U had a wink it would be looking at u :rolleyes: NOT Keep going be very carful have fun

Dale every time I see that picture it makes me smile. Vesuvius could erupt while U were underneath.

Otto very informative response in terms of helping everyone understand complexities of the chassis and the trials and tribulations of working thru issues. We R defiantly not all the same.In a word challenging. Be looking for a thread on Rockwell discs too.

12-21-2013, 12:50 PM
Joe and all, I do not have a pit but I have access to one at any time. One of my questions is where do I start? front to back, one side then the other, one type of replacement then another? Do the hoses need to be replaced along with the fittings? How much time should I budget for this project? Any idea how much the parts should cost? Should I do it myself or hire someone? Should I replace everything since the conversion was from a 1996 base?

I am mostly retired, I work about 4 days a month, do a fair amount of volunteer work, and spend many hours with my wife.

Joe Camper
12-21-2013, 02:23 PM
U do not have to have a pit.

Im guessing (I love doing that) U have a straight axle. Do say.

However if U do not the upper a arms for IFS R 600 a piece. If the grease boots on the tierods for IFS (3 tie rod assemblies for IFS center left and right) r bad and that bothers U even tho the knuckle is still tight yank them and replace with new assemblies all three r under 600 bucks and only very slightly more than just buying ends. Unless U r working with a puller to take tie rods loose even if the knuckle is still tight u will need to replace them if removing with the heat of a torch to get it loose. There is hard plastic in many tie rods and ball joints that the heat can potentially ruin. Ive got them out with heat way easier than with a stinking puller. Flip for new assemblies if your boots R shot. U can try wacking them cold u might get lucky with a puller don't count on it.

Back to the parts for U Otto.

Front bags straight axle 175 bucks IFS 200.

Shocks Monroe gas matic 45 bucks a piece 8 or 10 shocks depending on if u have 2 or 4 shocks on the straight axle that incidentally if u don't now u should upgrade to.

ride height valves r 100 bucks u have 3 linkage kits for the same 50 for 3

your service brake diaphragm on the steer is a 24 it is less than 10 bucks.

U can make up a bran new set of 1/2 rubber brake hoses with 2 piece reuseable ends with swivles for about 70 a piece there R six that I regularly do . If your bus already has the correct hose ends 5 bucks a hose gets those replaced.

the 3 position and the 2 position norgren for the straight axle front end r 200 for the both.

The 2 2position norgrens for the IFS front axle R 150 bucks for the 2

Some have decided to replace the norgren air manifold assembly that is the heart of the level low system it is mounted on the back wall under the drivers seat. Its 350 or 375 all these prices r estimates but very close.

Other than the dirt boot for the drag link in the front left wheel well 100 bucks that r the front.

Rear 6 bags 900 bucks

2 big norgrens 2 small 400 bucks

the shocks and ride height valves and the brake hoses for the rear we already have noted above.

the 30/36 brake chambers for the drive axle r 350 for the pair

the 24/16s for the tag r pricy 3 something a piece not a common item at all and that's why.

I would be amazed if U needed pads on the drive axle drum brakes.

pads for the Rockwell disc r 300 bucks per axle (4pads)

We have 14 radius rods on the bus these r the bars with rubber bushings that keep the axles attached to the carriage. Expect to need none. If any the 2 on the back end of the lower bar on the tag MIGHT be a bit worn maybe but probably not. The rest will be fine. Radius rod bushings r 10 bucks a piece

It used to be about 4 days work but im not getting any younger.

If U have the time and aptitude I will walk U thru it right here. We could do 1 corner at a Rally maybe? Or I will come to Carolina do it with U.

12-21-2013, 09:12 PM
That looks like a good Idea, But how much room if your bags fully deflated on you would you have underneath I noticed your bags look like they were at about ride height, mine will cover the tire with the fender skirts when I lower it I'm not sure if they can go any farther? also did you use 3/4 " plywood?

12-21-2013, 09:40 PM
Two year ago , the coach drove fine but I kept hearing a clank on bumps, I looked up under the front end and to my suprise the Dog bone Bushings were not just bad they were all gone !! Rubber 1 piece and they had all rotted out so I took it to the shop saw they were all the same MIA anyway I went with the two piece red replacments kinda like nylon I thought they might last longer at the time I had a ball joint boot torn so I had them just replace the ball joints on both sides and the top ball joint arms on both sides,
I thought they said the leveling system ran off the bar across the front end and the bar ran to the dog bones which had about 2" of play in them with no bushings, Now it seems when my bus auto levels it is always low in the front and on the drivers side Just like the bubble in the glass says so I end up doing it manually, (which with my leak does not last long right now :mad:)
My cousin is a custom Welder so if I could figure out a better football tank I would have him make a bunch, I hate fixing something more than once !! I know some thing cant be avoided,,,

Dick in Wisconsin
12-22-2013, 10:14 AM

This is what I built and used before I installed my pit. They work under the front or rear. They take a few sheets of plywood, glue and screws or nails.

Dale: How do you keep from driving the bus off the end? It looks a little steep to me, but I suppose the bus just crawls up the hill without any trouble.

Joe Camper
12-22-2013, 12:19 PM
Larry what U described was the sway bar bushings that R looing like the bigger radius rods. Go get on a knee and look at the tag from the rear U will see that lower oneeasy. IFS is nothing like the straight axle that has the big rods on the steer same as on the rear.

IMHO the red devils (ism for sway bar bushings) U used r not too good not as good as the black rubber replacements. The red ones crumble to bits and literally disappear. Never saw a black one do that keep an eye in them.

If the driving mode ride height is correct at the front and left follow Gills suggestion. The little gyro thingi that controls that is about 4 or 5 inches in diameter and looks like a little UFO exactly a little saucer. Its on 3 short 3in sprung legs mounted at their feet with adjustment screws on each. Adjust it there.

Bunches of Vantare Hs out there where is this item at boys

U R very correct about the blown sway bar bushings affecting the ride height on IFS the linkage arm for the ride height valve is mounted right to the bar and it drops without its rubbers.

Otto U snuck a comment in there EVERYONE should have asked U about immediately me included.

U said U discovered only 1 axle on the bus that had brakes after an early trip. Please expand on that A BUNCH I guess multiple issues and different reasons at specific axles??

Please tell we all want to know. Good safe driving on your part. Thank God U didn't run up on a backup or something on the way down.

I hate going down mountains straight shots R fine but usually they curve and limit how far ahead U can see around the bend. If there was a wreck around one of the curves blocking all lanes could I stop. That's what I ask myself the whole way down. Kinda ruins the site seeing for the driver. Even at the slower safe speed there is no time for distractions.

Otto what was the problem with your brakes?

Joe Camper
12-22-2013, 01:58 PM
Otto Read this thread and let your son read it too.


This is the perfect thread to hook this link to.

Greg what ever did U learn about the tag brakes.

dale farley
12-22-2013, 03:26 PM
This is some great info. At some point, I must check all these components on my bus.


Once you get under the bus, you can sit up. The most dangerous part is crawling under the side. The ramps give you almost another foot of headroom. I did use 3/4 plywood. At one point, i think i posted a material list and instructions. I'll look when i get a chance.


I have Paulette tell me when to stop. I placed the short 2'x4's at the start of the ramp because it would drag the bottom of the bus if the bus was lowered. I didn't have a problem with the bus pulling the incline. I'ts about the same as my driveway.

12-22-2013, 09:36 PM
Joe, Not being a mechanic I will give the what I understand happened to our brakes. The calipers were FROZEN in place. That meant that they did not apply pressure onto the brake pad. The way air brakes work as I understand it is that the fault position occurs when there is loss of air. When that happens the brakes automatically apply pressure to the brake pad and you stop. IF the calipers are frozen in place that fail safe mechanism cannot happen and you have NO brakes. The first time I went down the long steep mountain just east of Asheville/Black Mountain in North Carolina I used the Jake system to go very slowly down the mountain. I still had to use the brakes to keep my speed below 35. About 2/3rds of the way down the mountain smoke started coming out from the drivers rear tire area. There was no flame but there was smoke. I pulled over and waited...and waited...and waited. About 20 or 30 minutes later when all the smoke had cleared I used the lowest setting on the Jake and made it down the rest of the way with no problem. After I returned home (there is very little slope the rest of the trip to eastern North Carolina) I took the RV to our friend and mechanic. He almost turned white. We were very close to having a fire going down the mountain and only ONE brake was operating. We had to replace nearly everything on the rear braking system. Now everything is fine but we dodged a disaster. Had the brakes caught on fire the fire could very likely have spread to tires and on from there.

In retrospect what have I learned? Have a knowledgeable mechanic look at your brakes by taking off the tires, examine the movement of the calipers. You can watch them move when you test the brakes with the tires are off. The other thing I learned is to properly use the Jake system. This fall we returned to the same campground at Black Mountain for a week stay. Once again we had to go down that long steep mountain on our return home. I had full confidence in all the work we had done to our brakes but still....a few prayers were said at the top of the mountain.

I used the lowest setting on the Jake system, monitored our speed closely, and started the decline. It was a cake walk. I did not have to use the brakes at all. I can now tell a big difference in our stopping distance with the new brakes. I now know what good brakes are compared to very faulty ones.


Joe Camper
12-22-2013, 09:59 PM
Steep learning curve no pun intended. Very lucky it did not flame up directly after stopping if on the verge that's often what happens. Sometimes better to not stop right at the bottom. What U don't realize is stuff is GLOWING RED at this point if U really heated things up and stopping at that point flares up flames. Otto if its any concession this fact tells me U probably weren't glowing red yet or U would have flamed up. I flamed up a brake on a truck by stopping and was able to run back to the cab get rolling again put it out and cool it back down. If any others ever go thru similar conditions and approach the bottom or close to it with a brake smoking hot. If U can SLOWLY and SAFLEY SLOWLY keep rolling for any period of time after the grade is behind U the longer that time u can slowly roll better the chances r that when u do stop they wont flame up when U do. Getting out with an extinguisher in hand when U do wouldn't hurt either .

Not only were the service brakes not working if the calipers were stuck but the parking brake was also affected negatively. I was told once when u R at the top of the hill the decisions U make R what U will be dealing with at the bottom.

I think unfamiliar roads tend to get us more cautious. Its those last 2 pulls on the way back to the barn that U have driven 100 times before that's where we tend to get too comfortable behind the wheel maybe a bit too often.

Otto U got that pit. now that U have new stuff with the pit pull in there block the wheels release the parking brakes . Go under and grab all the calipers and jiggle them they should jiggle if they r not stuck when U release the parking brake. Do this every time U grease

Badda bing badda bang in like flint ect ect

Another thing grease monkeys that would not hurt, defiantly fall into the category of good stewardship and weather U have automatic slack adjusters or not. Weather U have Rockwell or Knore Bremse disc.

Every so often when U grease back the slacks all the way off and exercise them full stroke. grease them all the way backed off. Back off the calipers and slide them to and fro a couple times. If U always have manual brakes adjusted correctly or never have an auto adjuster fail this will defiantly prolong their lifespan. Its a good thing (a Martha Stewert ism)
I know of no other person on the web or elsewhere that has ever suggested this. I assure U this is good practice. Your bus will smile U will defiantly see it.

There is a thread where I went thru this somewhere. I also eluded to this kind of thing recently by mentioning the 20 yr anniversary for the introduction of the 60 series. Otto your story is becoming familure to me and thank U for sharing that .


Joe Camper
12-22-2013, 11:29 PM
Here U go Otto another link repetitive but this is how we learn right?


How come I only got 6 friends on my personal page here. U guys r hurting my feelings who else loves U like I do.

12-23-2013, 06:58 AM

We're all friends here so no need to use the Friends feature.

While talking brakes, I have a brake noise that drives me nuts. My font passenger side brake makes a loud vibrating squeal almost any time I use the brakes. More than one shop has said I have plenty of pad. Prevost thought it was too tight and adjusted it. Any ideas?

Joe Camper
12-23-2013, 10:09 AM
Gill I was am going stir crazy was just joking.

A vibrating squeal that a new term. Iduno possibly something came in contact with and has contaminated the Pads.

Pull the pads on the front and switch the sides see what happens that's no doe just a few minutes.

Soooo prevo adjusted them Hu. Know what that did? Oooooooooh boy, I made a promise to myself not to badmouth other mechanics and shops. I do not like it when it is done to me and wont do it to others.

So lets respond to that by saying after the 2nd or 3 rd time U hit the pedal after they backed them off, if the adjuster is working, that caliper was right back where it was before they backed it off. Probably didn't even make it back to the highway maybe not even out of the parking lot and it got right back where it was.

Being a steer axle they could not have backed it off too far that would have been dangerous and u would have had a pull on the wheel.

Tell me they told U all this and this adjustment would only create a different scenario for a very short time till the brake adjusts back up by itself. Every time U hit the brake with a loose caliper U make 1 click towards adjusted and Id be surprised if they backed that hub off more than 2 or 3 clicks. Had to hit the brakes first time as it got backed out of the garage that's 1 see what im saying.

Switch the pads left to right try that I can come over and do that for or with u. U can feed me something (edible) hows that sound? lemeno

Joe Camper
12-23-2013, 06:54 PM
Gill do u have a 98 chassis. If so what disc R on yours Rockwell or Knore bremse. Or, do u have slacks on the steer and tag or not?

Im still trying to figure out when they changed the XLs I think (guess) the Hs in 98 already went over to the newer Knore Bremse first that happened alot too Hs got stuff first.

Ive worked on 90 or 91 Hs with Rockwell disc and also worked on a 93 xl that still had drums all 3 axles.

Whats under that thing Gill?

12-23-2013, 10:23 PM
My Set up is 45 ft rig then motorcycle lift then fully loaded 4 door jeep rubicon filled with water and fuel I would hate to ever go over a scale and at the end of the jeep a Bike rack with 2 bikes I am guessing 73 ft and ?5,000lbs when I get close to those 16 mile 6% grades Down I get shifted down to maybe third gear and 2nd on on the jake brake, set cruise on 45 or 50 depending on corners you can always shift up but once you get her rolling you have to hit the brakes to get her to shift down I hardly ever need my brakes I let it slide down nice and smooth, Roll it out to the Flats and out to the Hammer lane :cool:

12-23-2013, 10:33 PM
I hate to hear about my choice about the red Two piece Bushings because what was left of the one piece black bushing in a couple of the Dog Bone Bushings were just disintegrated my coach is approximately 14 or 15 yrs old 2000 conversion so 98 or 99 Bus, I just thought after seeing that rubber one piece I didn't want that to happen again ??? See 53 yrs old and I am still making Bad decisions :mad:

Joe Camper
12-24-2013, 06:39 AM
No big deal U would think the red ones r better but I just don't think they r. Ive never seen a black one go like the red ones . just learned something with your comment.

12-24-2013, 08:13 AM

Yea, I have 98 chassis. Given there is a K on the caliper I guess I have Knore brakes. All slack adjusters are automatic. Discs on front and tag, drums on the drive. I too wondered how they could loosen the brakes with auto adjusters. I know that would be impossible on old fashioned auto drum brakes, but have never inspected the brakes on this enough to know how they work.

dale farley
12-24-2013, 09:08 AM

If it is any consolation to you, you are not by yourself. Everyone I know that has changed them, used the red/orange ones. I didn't even know the black ones were available.

Joe Camper
12-24-2013, 09:54 AM
Gill U have Rockwell brakes. Knore Bremse don't have the olds style auto adjusters slid on the spline of an s-cam.

They have integrated the adjuster right into the caliper and eliminated the separate large heavy old style auto slacks all together with the new design.

Im going to get a bunch more better pictures than I currently have on Rockwell R&R on the next one I do and show all the little idiosyncrasies and some of the issues I see encounter and suggestions for grease monkeys on Rockwell.

I went by my local truck parts guy with a caliper slide rebuild kit. Ive been ordering a few of these and wanted to see if it was available. Had a very interesting conversation.

I asked him R there any heavy trucks using IFS NO

R there any air ride front suspensions on them out there yes 1 in 1000. He also said the design is terrible the king pin and the axle R 1 piece and the spindles r 2 piece u separate them to remove them off the king pins and if the king pins r bad U buy a new axle. Also mentioned it absolutely does not hold up off road.

Next question how many big trucks r using disc brakes maybe 1 in 100 of his customers and it is Meritor not Knore Bremse. The newer design is similar Meritor also integrated the adjusters into the caliper however very few truck service centers r going to be familiar with our stuff

Point being when U have work done on the disc stuff due diligence would be pertinent.

This also means that we narrowed down when the XL went from Rockwell to Knore Bremse it as late 98 or early 99 cause I know Paul and Janice Horner had a 99 chassis and it had Knor Bremse and Gills 98 chassis does not.

12-24-2013, 10:45 AM
Hey Joe,

Here's a pic I took when having tires changed. Now I don't know if this is from the tag or steer.

Joe Camper
09-07-2014, 08:59 PM
That is a Knore Bremse Caliper Gill.

I have seen XLs A Angola in particular that had drum brakes on the drives Rockwell disc on the tag and knore bremse on the steer. I guess it is the tag because the caliper on the steer is centered on top that looks like it is rearward and the tag axle.

Keep lookin at that picture over and over. U don't have a whole lot of pad there Mr bus driver. Maybe its just the angle but I don't think so.

Joe Camper
09-07-2014, 09:27 PM
Found a new leak on a bus today that until now did not even know the fitting existed.

IFS - Front Axle - Air bag air tank (football), (lewism) passenger side.

In addition to the obvious ports on the tank IE inlet, outlet and drain plug I have now discovered that there is a 4th opening that prevo puts a plug in because it is not used. It is facing REARWARD and can only be seen if really looking for it. It is in a spot that even if u wanted u cant wet it down enough to check it when looking for leaks.

I had a 1/4 in a day drop in front suspension that led me to it.

First I separated the 2 front sides and pressure tested them. that lead me to the passenger side. I went on to air the bag by itself and the norgren by itself and the air tank with the existing inlet and outlet lines by itself. Found the football to be the leak. So I pulled it.

U have to pull the sway bar out of the way to get the front footballs out on IFS but its not too bad.

Expected to see another pinhole was surprised to discover that rearward plug was not tight enough and bubbling.

Did U know that there r 3, 2 position norgrens that can make u drop in front if U have IFS. Not just the 2 in the suspension tower by the ride height valve there is another in the steering bay. All 3 remain in play key off.

Now U know the rest of the story.

Joe Camper
11-04-2015, 01:27 PM
As the newer style suspensions age I am uncovering more and more of these airbag air tanks rotted rusted and leaking.

If your in a 2000 or so chassis be prepared to uncover a bad one when doing bags. These tanks have push in fittings that most want gone so pull the tank when replacing the air bags and push in fittings so u can take a good look at it.

IMHO or if I had a newer chassis and was very proactive with things I'd pull them just to put some better additional paint on the tank and the bracket that will very posibly eliminate the rot.

Also there is no ryme or reason to it. U would think the one for the tag bag that is mounted outboard by the tire wad prone but it's the 2 for the rear drive bags that I have encountered most frequently going bad.

Hmmmm. 8 page thread what knucklehead started this thread anyway??

Joe Camper
11-04-2015, 04:45 PM
And another thing. On 2000 to 2005 aproximity but for 10 yr or possibly more I don't know I'm giving info from bus chassis I have put my hands on and in that location.

Shew that was a mouthful wasn't it.

Directly above the air tanks for the rear air bags for the drive axle there are 2 r12 brake relay valves. The signal line for them is going in the top. It is 1/4 in plastic and is inserted into a Mr nipple nuts push in fitting.

If this begins to leak it will drain the air tanks key off. I have encountered 4 such leaky signal lines to these r12 brake relay valve.

This is a very difficult repair to make with all the wheels and suspension in place. Many of u have it.

So again if doing air bags in addition to doing some painting and rust prevention on those football air bag tanks u should certainly reach up and get the stupid push in fitting from those valves when u r in there.

And another thing I'm seeing is a sgnificant amount of rust jacking on the upper and lower air bag mounting surface. I chipped off what looks like pieces of slate 1/4 even aproaching 1/2in thick. Knock it off and hit them with pour 30 that's what I use. I see enough of this to define it as common.

What else?? I'LL think of somthin.