Reply
 
Thread Tools Search this Thread Display Modes
 
Old 01-27-2004, 07:14 AM   #1
Still Working
 
smily's Avatar
 
1994 36' Classic 36
North Charleston , South Carolina
Join Date: Jul 2002
Posts: 1,681
Images: 19
Droopy Rear End (Motorhome)

The rear end on the driver side of my 1990, 33' LY leans low in the rear of the coach. It is very obvious.

My air system seems to be working okay and holding pressure.

I may have a slow leak in rear bags but I have not determined that. I have replaced the front Airbags with new ones. The front Airbags are independant of the air compressor system. You add air individually to the front Airbags via dedicated hoses.

The rear end sits low even with air system fully charged and the compressor has stopped running. (should the compressor come on everytime I start the MH?)

I suspect something is awry with the rear suspension.

Any thoughts on this?

Smily
__________________

smily is offline   Reply With Quote
Old 01-27-2004, 07:29 AM   #2
Rivet Master
 
wb13798's Avatar
 
2004 28' Classic
Currently Looking...
huntsville , Alabama
Join Date: Jul 2002
Posts: 866
Images: 1
sound like you have two leveling valves. if so it isnt a big deal . just adjust one to mach the other. is that the stolen motor home???
__________________

__________________
AL
2007 chevrolet 2500 duramax 6.6
allison 6 speed
2004 classic 28 WB , Pro Pride P-3 hitch
centramatics wheel ballancers 300-556
wb13798 is offline   Reply With Quote
Old 01-27-2004, 07:40 AM   #3
Still Working
 
smily's Avatar
 
1994 36' Classic 36
North Charleston , South Carolina
Join Date: Jul 2002
Posts: 1,681
Images: 19
Location

Where are the valves?

Smily
smily is offline   Reply With Quote
Old 01-27-2004, 07:45 AM   #4
Just a member
 
thenewkid64's Avatar
 
1978 28' Argosy 28
Tampa Bay , Florida
Join Date: Mar 2002
Posts: 4,541
Images: 21
Send a message via AIM to thenewkid64 Send a message via Yahoo to thenewkid64 Send a message via Skype™ to thenewkid64
The best way to find the valves is to look at the bottom edge of the rear axle, normally next to the bags. There will be a rod that goes up toward the floor. The valve will be at the top of this rod. I have the same issue since I replaced by bags so I am going to have to spend some time on my back checking the fittings and lines. I may just have one that is a bit loose. While you are under there it is a good time to inspect the bags themselves. Look for cracking or flaking. If you see either you may need to get them on the list for replacement. Replace them in pairs.
__________________
Brett G
WBCCI #5501 AIR # 49
-------------------------
1978 Argosy 28 foot Motorhome

Wise men talk because they have something to say; fools, because they have to say something. -- Plato


thenewkid64 is offline   Reply With Quote
Old 01-27-2004, 07:52 AM   #5
Still Working
 
smily's Avatar
 
1994 36' Classic 36
North Charleston , South Carolina
Join Date: Jul 2002
Posts: 1,681
Images: 19
Compressor cycle

Should the bags hold pressure all of the time or do they bleed down when the compressor is not running?
Why does my compressor come on at cold start and run for about 4 minutes prior to shutting off?

It may be cycling during driving but I cannot hear it if there is cycling.

My pressure guage seems to indicate that there is around 120 pounds while running down the road. I say 120lbs but may be off. It indicates in the green area, (good).

Smily
smily is offline   Reply With Quote
Old 01-27-2004, 08:00 AM   #6
Rivet Master
 
87MH's Avatar
 
1978 31' Sovereign
Texas Airstream Harbor , Zavalla, in the Deep East Texas Piney Woods on Lake Sam Rayburn
Join Date: Jan 2003
Posts: 2,435
Images: 292
Is there a tag axel?

Ken,

On the tag axel classics the air bag sensors are on the trailing arms of the torque rod to wheel axel assembly. One on either side.

Easy logic, since the tag axel is completely independent of the air bag suspension, if the tag axel wheels get too close to the underbody of the coach, the leveling controls think "hey, the tag axel is carrying too much weight", and send more air to the bags so the main drive axel takes more weight. Conversly, if the tag axel wheels are too far away from the under floor (too much angle in the tag suspension), the sensors think"hey, got to add more weight to the tag suspension", and bleed air from the bags, allowing the coach to settle down, putting more weight on the tag axel wheels.

Hope this helps.
__________________
Dennis

"Suck it up, spend the bucks, do it right the first time."

WBCCI # 1113
AirForums #1737

Trailer '78 31' Sovereign

Living Large at an Airstream Park on the Largest Lake Totally Contained in Texas
Texas Airstream Harbor, Inc.
87MH is offline   Reply With Quote
Old 01-27-2004, 08:06 AM   #7
Still Working
 
smily's Avatar
 
1994 36' Classic 36
North Charleston , South Carolina
Join Date: Jul 2002
Posts: 1,681
Images: 19
Huh?

Yes there is a tag axle

So what are you saying?

Are you implying that the Tag axle sensors are either bad or not working properly?

If so, what does the sensor look like? can you get a replacement?
Is is electronic? If so what does it talk to, valve, compressor,.......?

Smily
smily is offline   Reply With Quote
Old 01-27-2004, 08:08 AM   #8
Rivet Master
 
87MH's Avatar
 
1978 31' Sovereign
Texas Airstream Harbor , Zavalla, in the Deep East Texas Piney Woods on Lake Sam Rayburn
Join Date: Jan 2003
Posts: 2,435
Images: 292
My pressure guage seems to indicate that there is around 120 pounds while running dow

Ken,

That is good. The compressors are single stage, and that (120 psi) is about the upper limit for single stage air compression.

If you are carrying 120 psi in the volume tank, I would say you would have to look downstream from there for any problems.

As far as the suspension system bleeding off during non-use, on the Xeppelin, that is normal. Whenever I put down the rear jacks, and take a little weight off of the rear suspension, the tags develope a bit more ositive angle, and, according to my previous post, proceed to dump air from the bags in an attemto to bring the tags up to their "normal" level. Of course, with the jacks down, this can't happen. So, for me, a transfer of air from the volume tank to the air bags is normal whenever I come down off of the jacks.

Right now, I do not know what pressure is normally in the bags at my usual road weight.

Interesting question, I'll post after getting a bag pressure readout.
__________________
Dennis

"Suck it up, spend the bucks, do it right the first time."

WBCCI # 1113
AirForums #1737

Trailer '78 31' Sovereign

Living Large at an Airstream Park on the Largest Lake Totally Contained in Texas
Texas Airstream Harbor, Inc.
87MH is offline   Reply With Quote
Old 01-27-2004, 08:19 AM   #9
Rivet Master
 
87MH's Avatar
 
1978 31' Sovereign
Texas Airstream Harbor , Zavalla, in the Deep East Texas Piney Woods on Lake Sam Rayburn
Join Date: Jan 2003
Posts: 2,435
Images: 292
Sensors

Ken,

The sensors are simple pneumatic devices (on the Xeppelin, anyway), the early 80's single axels suspension used solenoid controls. On most of the 80's era air streams, the coltrol arms can be quickly identified, just look for anything with an incredably bad weld job on the control arms. Just look under the coach. They will be easy to spot.
Attached Thumbnails
Click image for larger version

Name:	air suspension.jpg
Views:	557
Size:	50.1 KB
ID:	4593  
__________________
Dennis

"Suck it up, spend the bucks, do it right the first time."

WBCCI # 1113
AirForums #1737

Trailer '78 31' Sovereign

Living Large at an Airstream Park on the Largest Lake Totally Contained in Texas
Texas Airstream Harbor, Inc.
87MH is offline   Reply With Quote
Old 01-27-2004, 08:22 AM   #10
Still Working
 
smily's Avatar
 
1994 36' Classic 36
North Charleston , South Carolina
Join Date: Jul 2002
Posts: 1,681
Images: 19
Not the same situation

My compressor runs even if I have not deployed jacks.

I am asking if the bags bleed down everytime you shut off engine.

Or, are they supposed to maintain last pressure rating prior to shutoff.

Am I making any sense?

Smily
smily is offline   Reply With Quote
Old 01-27-2004, 08:29 AM   #11
Still Working
 
smily's Avatar
 
1994 36' Classic 36
North Charleston , South Carolina
Join Date: Jul 2002
Posts: 1,681
Images: 19
Valves

Thanks for the depiction.

I have a valve on the passenger side just rear of the tag axle that protrudes from the bottom of the side panels.

It has a shrader valve and a cutoff valve . I opened this cutoff valve once, (briefly) and air escaped the valve. I immediately closed it.

There is not a valve on the driver side of the coach.

I have been wondering what this valve is for. It appeared to be a method for adding air to the system but apparently it is for releasing air. (I guess)

Smily
smily is offline   Reply With Quote
Old 01-27-2004, 08:32 AM   #12
Rivet Master
 
87MH's Avatar
 
1978 31' Sovereign
Texas Airstream Harbor , Zavalla, in the Deep East Texas Piney Woods on Lake Sam Rayburn
Join Date: Jan 2003
Posts: 2,435
Images: 292
I am asking if the bags bleed down everytime you shut off engine.

Ken:

The answer to your question is definitely "no".

Once the system is static, under normal circumstances, there should be no transfer of air either into or out of the bags. As stated earlier, once the leveling sensors adjust to the proper angle, they have done their job, and everything should remain pressured up.

If you think the system is bleeding down quickly, you should be able to hear the air leaking off after shutdown, and a leak that large would be easy to locate.

As part of the troubleshooting, I would recommend getting an accurate weight on all three of the axels. At least that would tell you if the tag axel is carrying too much weight (bag or sensor problem), or not enough (torsion axel rubber problem in the tag).

On edit......or, worst case scenario, the whole thing is overloaded and there is just too much weight in the rear overhang for the suspension to compensate.
__________________
Dennis

"Suck it up, spend the bucks, do it right the first time."

WBCCI # 1113
AirForums #1737

Trailer '78 31' Sovereign

Living Large at an Airstream Park on the Largest Lake Totally Contained in Texas
Texas Airstream Harbor, Inc.
87MH is offline   Reply With Quote
Old 01-27-2004, 08:37 AM   #13
Still Working
 
smily's Avatar
 
1994 36' Classic 36
North Charleston , South Carolina
Join Date: Jul 2002
Posts: 1,681
Images: 19
Thanks

I have listened for leaks and nothing obvious but I will get under vehicle and check a little closer.

The only indication I have of any bleeding is the fact that my compressor comes on everytime I start vehicle. It runs for about 3 to 4 minutes before shutting off. Is this normal?

I realize I may be asking the same question more than once, bear with me.
I am used to giving answers not questions.

Smily
smily is offline   Reply With Quote
Old 01-27-2004, 08:47 AM   #14
Rivet Master
 
87MH's Avatar
 
1978 31' Sovereign
Texas Airstream Harbor , Zavalla, in the Deep East Texas Piney Woods on Lake Sam Rayburn
Join Date: Jan 2003
Posts: 2,435
Images: 292
Good Question

"The only indication I have of any bleeding is the fact that my compressor comes on everytime I start vehicle. It runs for about 3 to 4 minutes before shutting off. Is this normal?"

Ken,

Don't know.

The PO put a HUGE compressor in. The compressor is mounted all the way to the rear of the coach, under the bed. I can't hear if it comes on or not from the drivers seat, it is that quiet.

I can tell you, that since getting the electricals to it straightened out (too small of a wire feeding the motor), unless I lower the rear jacks to the point that the sensors dump the bag air, (I can hear the air bleeding, but I know this is normal), my air system does not bleed off.

The Xeppelin does not have an air pressure guage, only an idiot light mounted in the dash, but the light has not come on since upgrading the feed wire, and the air suspension brings itself to normal (usually) as soon as I get down off of the jacks. On rare occasion it takes a slight movement (forward motion of the vehicles length) for the air sensors to pick up the change and compensate.
__________________
Dennis

"Suck it up, spend the bucks, do it right the first time."

WBCCI # 1113
AirForums #1737

Trailer '78 31' Sovereign

Living Large at an Airstream Park on the Largest Lake Totally Contained in Texas
Texas Airstream Harbor, Inc.
87MH is offline   Reply With Quote
Old 01-27-2004, 08:55 AM   #15
Rivet Master
 
wb13798's Avatar
 
2004 28' Classic
Currently Looking...
huntsville , Alabama
Join Date: Jul 2002
Posts: 866
Images: 1
does the guage your looking at indicate a change in air pressure??? sounds like you are venting air some where for some reason. that isnt much help but if the compressor only comes on when you start the coach i wouldnt worry about it.
as brett suggested look at the bags and see if they are in good shape . on my tank i have a shrader valve check the pressure there and wait a day and check it again . then you will know for sure it is venting . most cases it is venting thru the compressor as the check valve is stuck partially open
__________________
AL
2007 chevrolet 2500 duramax 6.6
allison 6 speed
2004 classic 28 WB , Pro Pride P-3 hitch
centramatics wheel ballancers 300-556
wb13798 is offline   Reply With Quote
Old 01-27-2004, 10:02 AM   #16
Still Working
 
smily's Avatar
 
1994 36' Classic 36
North Charleston , South Carolina
Join Date: Jul 2002
Posts: 1,681
Images: 19
Update

I just got off the phone with Phred Sez and he tells me that Brakes are Air over hydraulic and that is why the compressor fires up, to pressurize braking system.

Compressor should run on initial startup.

Thanks Phred,
Smily
smily is offline   Reply With Quote
Old 01-27-2004, 11:21 AM   #17
Rivet Master
 
LOST , Hawaii
Join Date: Jun 2002
Posts: 2,193
I would double check on that. I can't imagine a manufacturer using a 12v compressor as part of a braking system. I have also never seen an air over hydraulic on a p32.

Look at your PS pump. Does it have lines going to the master cylinder? If so it is a hydoboost and not air over hydraulic.

John
74Argosy24MH is offline   Reply With Quote
Old 01-27-2004, 11:32 AM   #18
Just a member
 
thenewkid64's Avatar
 
1978 28' Argosy 28
Tampa Bay , Florida
Join Date: Mar 2002
Posts: 4,541
Images: 21
Send a message via AIM to thenewkid64 Send a message via Yahoo to thenewkid64 Send a message via Skype™ to thenewkid64
Ken,

Fred's MH is a diesel pusher, he has an air over hydraulic system. I don't think that the p-30 series chassis came with that type of setup. Normally it is a hydro boost like John mentioned above.

If you are using the jacks to level the coach you could be causing the leak down. On mine if I use my stabilizer jacks and lift the coach to finish leveling (they are 5K rated screw jacks) I will dump some air. Then when I set it down the rear will sit out of level until I power up the compressor and the bags refill.

There may also be a section of the system that does not maintain the 120 PSI. This is normally to prevent the compressor from having to start against a high head pressure situation.

All in all I think you have a small leak. I would start at the bags themselves and check condition, then look at leak testing all of the fittings. One other option is to set the jacks, leave it for 5-7 days and see what bags(s) are soft. Then troubleshoot toward the compressor from there.

Most of the OEM compressors are rated for 20-30% duty cycle, so even if you continue to use the coach you should not cause additional harm to the components, I would be more concerned for a failure of some sort while on a trip. If it was a bag, it took me 3 months to get mine
__________________
Brett G
WBCCI #5501 AIR # 49
-------------------------
1978 Argosy 28 foot Motorhome

Wise men talk because they have something to say; fools, because they have to say something. -- Plato


thenewkid64 is offline   Reply With Quote
Old 01-27-2004, 11:46 AM   #19
Still Working
 
smily's Avatar
 
1994 36' Classic 36
North Charleston , South Carolina
Join Date: Jul 2002
Posts: 1,681
Images: 19
Level

During lunch break I went over and looked at MH.
The unit sits almost 2 inches lower on driver side than the passenger side.

The bags appear to be in good condition but I did not get real good look all over the bag.

The shocks seem to be the same on each side.
The axle arm is practically level on each side, (neutral),

I cannot see a broken leaf spring but I did not get a good look.

As for Master cylinder, I know that there are directions for bleeding both master cylinder and steering pump. I know that the brakes are dependant on the belt system. I know this because when I had to stand on the brakes on the way home from Houston, the belts went to squeeling loudly.

Brett, I have not deployed jacks so I dont think that is a factor.

The leaf springs are adjustable on each side. There are three holes in the bracket. Each side is bolted to the lower most hole. Same on each side.

Tomorrow, I will take photos of everything and post for the gallery.

Smily
smily is offline   Reply With Quote
Old 01-27-2004, 12:34 PM   #20
Rivet Master
 
87MH's Avatar
 
1978 31' Sovereign
Texas Airstream Harbor , Zavalla, in the Deep East Texas Piney Woods on Lake Sam Rayburn
Join Date: Jan 2003
Posts: 2,435
Images: 292
Air, Brakes, and Scratching my Bald Head

I have to agree with John and Brett, the brakes are power steering pump assisted. I ran down to PPL at lunch and looked at a '92 on their lot, there was no mention of air over hydraulics in the '92 Chevy Chassis Service manual. It only mentioned vaccuum and steering hydraulic assist power units. Sweet use of space under the front hood.

Now, the '92 was squatted way low in the rear, way to low to be out on the road, so Ken's "low rider" may be endimic to the G2.

I would be concerned about a 2" lean to one side. Could be the bag, could be something else. My air beam is also mounted in the lowermost of the 3 holes in the spring/beam interconnect bracket.

I'd still highly recommend weighing the 3 axels - that will give you a starting point for mods and weights and balance. If you could weigh each side of each of the three axels, that would confirm or disprove that the lean is caused by too much weight on one side of the MH.

Ken, do you have an air pressure gauge mounted in the dash panel?
__________________

__________________
Dennis

"Suck it up, spend the bucks, do it right the first time."

WBCCI # 1113
AirForums #1737

Trailer '78 31' Sovereign

Living Large at an Airstream Park on the Largest Lake Totally Contained in Texas
Texas Airstream Harbor, Inc.
87MH is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 09:52 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
×