'87 Itasca 37RQ, Air Suspension Problem

87Itasca · January 12, 2016, 02:10 PM

Hi all,

I'm glad I stumbled across this forum, I think I'll stick around if you all will have me. I know an Itasca and a Winnebago are in the same family, so hopefully I'll get treated like a nephew or uncle, vs. an in-law.

I have recently purchased a nice low mileage Itasca Windcruiser, and I am slowly working on getting it ready for use. My current problem lies with the air suspension.

This model features a leaf spring drive axle, with air ride helper shocks, and a rear tag axle that is torsion sprung, and has a sensor that controls the amount of air in the air springs.

My compressor is burnt up completely, so I have temporarily removed it, and added a valve that allows me to add air to the system until I get a replacement compressor. The air springs have been replaced about 12 years and 8,000 miles ago, and still look to be in great shape. However, the cradle that they are mounted on appears to be angled forwards, causing the air spring bases to tilt towards the air tank, causing the springs to inflate at extreme angles when aired up, also resulting in the bags rubbing against the air tank.

I added 100 PSI to the system, which aired it up nicely (I think it can actually hold more air, but I didn't want to blow anything out), but it has started to leak out again. I want to fix my mounting issue first, then see where I may be leaking air at. The soapy water test does well for this.

How does this adjust exactly? Or is this how it's supposed to sit? Can anyone with one of these snap a photo, or confirm this for me?

This is really a great coach, and with 42K on it, it seems to still have a lot of life to give. I've got almost everything working, with only a couple bugs to find and fix.

Rickf1985 · January 12, 2016, 05:13 PM

First off do not put more than 100 lbs. in them. That is max and they should be at full height and hard as a rock, especially on a tag. I can't picture a torsion and air ride together. The bags need to be straight in line up and down. Something is wrong there. Can you get some more pictures of the rear suspension including the front differential? I can see that axle has a pivot point but it would have to come back substantially, that makes me wonder of something is missing or broken. I have seen pictures of the air ride on both axles but never spring on one and air on the other. Be aware that the Jet Ride suspension uses a cut off spring to locate the driving axle and then uses bags to lift it. Be sure this is not what you have. The leaf springs would end right behind the axle at the U-bolt.

Oh, Welcome to the forum! D:oH!

DaveVA78Chieftain · January 12, 2016, 06:54 PM

Go this post http://www.classicwinnebagos.com/forum/index.php?topic=10847.0 for information about the Superide system on your coach including a link to the original manufacturer of that tag axle system.

Also here is the parts book for your coach

Rickf1985 · January 12, 2016, 09:47 PM

I remember that post now! I had forgotten all about that. They used so many different systems under these things!

87Itasca · January 13, 2016, 09:46 AM

Hi all,

It looks nearly identical to the Superide 800 system. I just sent an email to the company to see if they may be able to offer any assistance.

The actual cradle the air springs sit on is behind the rear differential Rick. It's a supplement, more than anything. The differential position is unchanged by the way it sits now, although the coach does sit low to the ground because of it. The rear axle is torsion bar spring, to keep a preset amount of weigh on it at all times. The angle the tag axle sits in relation to the coach determines how much air pressure is needed in the air springs to keep it level.

Rickf1985 · January 13, 2016, 11:45 AM

I would have to see the whole axle in one picture to be able to wrap my head around it. Once I see the geometry I would understand it immediately but looking at the parts breakdown just isn't working because it does not show the axle relationship to the suspension.The one thing I can tell you is that these air bags are designed to work only on the up and down plane, not on a curve.

87Itasca · January 15, 2016, 08:31 AM

I'll try to get you pictures as best I can this weekend, I have no way to jack it up in the air at the moment, so it limits how much I can get under/around it to do some stuff that needs doing.

The folks at Superide called me a couple hours after I sent the email, and he provided me with an installation guide that gives instructions more or less on how to adjust the unit. Just need to re-read it to be sure of what I need to do. I'm not sure how it got tilted forwards like it did, the only thing I can think of is perhaps someone backing into a stump, or something along those lines. Thankfully nothing that I can see appears to be broken.

I do have an air leak, somewhere. It's slower, but a leak nonetheless. It takes about 3 days to fully settle to the lowest setting again. Once I get it straightened out, I'll do the soapy water test on everything and see where it may be coming from.

Rickf1985 · January 15, 2016, 07:56 PM

If someone back into something and that is why it is bent down then something MUST be bent. I don't see how it could be so far down just on adjustment. Be sure to look everything over very closely.

87Itasca · January 16, 2016, 09:22 AM

The whole assembly has an adjustment of about 130*, the guy said over the phone, but it's only designed to operate with it adjusted so the springs sit completely vertical. I'm going to try my best to take a look at it today if the ground dries out, and see what I can see. The nut that is visible in the edge of the picture is what I'm supposed to put a breaker bar on to pivot it. There are four nuts underneath the assembly I am supposed to loosen first, for the transverse link, but I don't know how I'm going to get to them.

Froggy1936 · January 16, 2016, 12:48 PM

What I did was drive the rear up onto 4x4 & 2x4 blocks and jack up the frt To be able to get under it The blocks in the rear can be doubled for more height Frank

cook elandan · January 16, 2016, 02:48 PM

I looked at my unit today, there is a center link that attaches in the middle between the airbags of the suspension unit to the cross frame. make sure that it is attached at all points. If it is broken it could allow the airbags twist the frame. I tried to attach some photos but not able. Photo bucket not working either.

cook elandan · January 16, 2016, 03:06 PM

just seeing if this link works.
http://s1078.photobucket.com/user/cookelandan/slideshow/1989%20elandan%20suspension

Rickf1985 · January 17, 2016, 08:45 PM

I just can't picture how that works. I see where it may be attached to the front, driving differential but I don't see any attachment to the tag. Sorry, I am not going to be any help on this one. One thing I did see in those pictures is there looks like a bolt going up over the label in the third picture. If that bolt is supposed to be tight it is not, look at the rust powder around it from motion. There is even a name for that rust, used when you see it on lugs on trucks but I can't remember it.

TerryH · January 17, 2016, 11:08 PM

Is it "rust trail" you're thinking of?

cook elandan · January 18, 2016, 02:17 AM

Rick, the tag axle is mounted to the frame by way of independent torsion arms. On the tag axle in one of the pics you can see the adjustment valve that controls the air for each bag. the valve has a delay before there is an adjustment. that way it is not always raising or lowing the MH every time the tag axles are not at their set point for the height you want the MH to ride at. course you know that the air bags are attached to the rear part of the leaf springs(cut off)for the drive axle.
The rust you are talking about may be the problem, the bolt rusted off and the link is no longer holding the air bags true. so with what we see with his MH, I had better be replacing my bolts or i may be in the same boat.

DaveVA78Chieftain · January 18, 2016, 08:22 AM

Rick
This thing replaces the rear spring perch so the spring is sort of floating on air so to speak. As shown in Figure 2 of the 800 Installation instruction, this thing does tilt some when the rig is loaded. Not sure how much tilt there should be though. However, his picture above gives me the impression this is attached to the driving axle, not the tag axle (mounted in between the 2 axles).

87Itasca · January 18, 2016, 09:27 AM

Hi all,

This is mounted to neither axle, but instead to the rear leaf bracket on the drive axle. The assembly sits between the axles, and does not physically attach to either in any way.

I loosened both the 24MM bolts, hoping I could "persuade" it to pivot with a BFH, but no luck. Going to have to figure something else out. Once I can get it in my shop, I can look at it better. It's going to be in the teens the next couple days, so no working on it until it warms up.

I was unable to take any photos on Sunday, as we got a rather unexpected snowstorm, which then quickly melted, leaving 2" of mud and slop everywhere. Thank you for the photos cookelandan, I'll use them to compare notes when I can.

No bolts have broken/rusted out of the assembly. There is only one per side, even the original installation manual shows this.

I will air it up at some point this week and snap a photo, so you can see what I mean about the spring angle.

cook elandan · January 18, 2016, 10:52 AM

87, I think that the center link is going to be your issue. there must be a bad bushing, bolt or a broken weld that is allowing the twist. the link is the only point that keeps the bags true. when i release all the air in the bags, the link points rest on each other and they are level with themselves. they look straight up and down from the ground.

Rickf1985 · January 18, 2016, 11:34 AM

That link is not designed to hold a side load, it is designed to keep the axle centered under the rig side to side. There has to be something holding the axle from the front or rear to stabilize the rotation.

cook elandan · January 18, 2016, 09:53 PM

Rick, here is a pic from American Carrier. the springs that are attached to the drive axle has the last quarter cut off and that is where the shackles are attached to that attached to the air spring cross member. you then have the two air bags that are attached to their platforms. and then you have the center link. I just went out and looked again and there are no other attachment points. I still believe that the center link controls the side to side movement along with keeping the air bag cross member true. it is a very stout link. now that is just for the drive axle. the tag is a different setup.

Rickf1985 · January 19, 2016, 09:00 AM

Here is what I needed to see! NOW I can see the relation between the axle and the bags. The bags sit in a cradle and the top sides of the cradle have the springs in them. THAT is the major centering factor, the weight pushing down on the cradle. The picture you show above shows the cradle arms but not the springs which is what was confusing me. On a drive axle especially you will have to have something attached to the axle to prevent axle wrap under power and braking. The leaf springs should be clamped to that axle as usual even if they are cut of behind. The tag axle will also need something to prevent wrap due to braking and that would be attached to the cradle in some way, shape or form to allow up and down movement but no forward or rearward movement. This has happened on yours and that is what needs to be addressed. Something has failed, not just gone out of adjustment. Again, I am no expert but I do know the bags will break at that angle.

87Itasca · February 01, 2016, 12:01 PM

Just an update everyone,

This is going to have to wait until I get it in the shop, where there is a concrete floor so I can jack it up. I loosened both the 24MM nuts where it looks like it would pivot, but it does not budge. Looks like I've got some air leaks now too.

Last time it stayed aired up for about 4 days, now air runs out of it as fast as I add it. I bypassed the whole compressor cutoff switch/solenoid etc. under the cabinet, and added a fitting directly to the feed line, which eliminated the worst of them, however there's a leak somewhere in all the stuff under the RV, as it will only stay aired up for a couple hours now.

As a bonus, I found the air lines for the front bags, and those are shot too.

Which bags do you guys use to replace these? They look like the Air Ride 1000 bags, but that seems like it's awfully undersized for a 5000# front axle.

Rickf1985 · February 01, 2016, 02:47 PM

The air bags in the front are only supposed to supplement the springs. My guess is that you need new front springs also, most of them at this age do.

cook elandan · February 03, 2016, 05:05 AM

87,
OK, I still think that your issue will be the center link that is between the airbags. Looking at your pic of the shackle, it should be perpendicular to the ground also the airbag pad should be horizontal. The way that it is twisted would have to be something with the center link is either bent or a weld is broken. Your bolt, if it is the one on the shackle connecting to the airbag frame, is a pivot point, not much of one but it does pivot.

87Itasca · February 08, 2016, 09:21 AM

Yes, the front air bags are shot too. One already was, the other held about 15 pounds before "pop!...ssssssssss". They were replaced before, the air lines have 3/95 stamped on them, but the bags were definitely used up. They were hard as a rock where they molded around each spring.

I got the left one in on Saturday, took me FIVE hours. I was so tired, sore, and bloodied I decided to hold off on the right side for a couple weekends.

I didn't air it up more than enough to expand the bag however, didn't want to take a chance and pop that bag if the other side wasn't aired up.

I'm not going to be able to do anything with the rear until I can get it jacked up enough to get under it cook. I may go the wood route that Froggy mentioned, I just have to find the wood I need. It's just been cold enough each weekend I haven't felt like laying on the ground outside. Plus there are other things to do with sealing seams, interior work, and whatnot.