Classic Winnebagos & Vintage RVs

Topic Boards => Chevy - GMC Chassis => Topic started by: 87Itasca on January 12, 2016, 02:10 PM

Title: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on 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.


(https://www.classicwinnebagos.com/forum/proxy.php?request=http%3A%2F%2Fi283.photobucket.com%2Falbums%2Fkk282%2F1994LTCSS%2F2988F260-3C57-4CC3-AC21-4D33DFC95677.jpg&hash=8c75dc1ff346e573a8b0d01221631862282444a2) (http://s283.photobucket.com/user/1994LTCSS/media/2988F260-3C57-4CC3-AC21-4D33DFC95677.jpg.html)
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on 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!
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: DaveVA78Chieftain on January 12, 2016, 06:54 PM
Go this post http://www.classicwinnebagos.com/forum/index.php?topic=10847.0 (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 (http://www.winnebagoind.com/service/wincd/1987/87icp37rq.pdf)
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on 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!
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on 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.

Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on 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.

Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Froggy1936 on 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
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: cook elandan on 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.

Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: cook elandan on January 16, 2016, 03:06 PM

just seeing if this link works.
http://s1078.photobucket.com/user/cookelandan/slideshow/1989%20elandan%20suspension
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: TerryH on January 17, 2016, 11:08 PM
Is it "rust trail" you're thinking of?
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: cook elandan on 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.   
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: DaveVA78Chieftain on 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).
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: cook elandan on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: cook elandan on January 18, 2016, 09:53 PM
(https://www.classicwinnebagos.com/forum/proxy.php?request=http%3A%2F%2Fsuperide1.com%2FPhotos%2F900series-b.jpg&hash=f543dad29af14a322c4f7422ae9d460342c9b540)
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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on 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.  :D

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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: cook elandan on 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.   
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on 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.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on February 08, 2016, 11:56 AM
When you make the ramps to drive up on what I used is 3/4 plywood cut into 24" squares along with 2x8 pressure treated lumber cut to various lengths to give me height and some run up length. If the coach is empty of water and most camping stuff you can use just the outer set of tires to run up on. I tend to use both, it takes more wood but I am going to be under there and I don't want it kicking out side ways. I try to get it up at least 6-8 inches high. What I do is back up to where I want to end up parked and move forward about two feet. Build your platform you will be parked on right at the back of the rear tire. Now pull forward and build the ramp to get up to the platform, this way you are sure that when you are all done the platform is even when you get there. I would back up until the tag is off of the platform and the front axle is on it, this way most of the weight is off of the tag and you can work on it. The other option is to build your platform in two sections, one for the main axle and one for the tag and then once you are in place and well chocked at the front you can slowly Jack up the tag and remove the sections of that platform and lower the tag bit by bit. May actually be better that way but a lot more blocking.



Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: cook elandan on February 10, 2016, 06:54 AM
Rick, sorry but he is not having any issue with the tag axle and allowing it to come back off the ramp will put too much stress on the components.  Leaving the tags on the ramp will keep them up and out of the way.  He is having issue with the orientation with the air bags that are attached to the drive axle. We just need to help him find out why his air bags are twisting. So he need to look at the three mounting points of the air bag system.  The shackles on the leaf springs, which we can see that they are attached.  Mounting pads of the air bags, they both appear to be twisted at the same rate, so they look to be ok.  Last is the center stabilizing link which we are not able to see by his pic.  With the twist in the air bag frame rail, I would say that there is a problem with the link. JMO.

Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on February 10, 2016, 08:11 AM
You're likely right. One of two things has to happen before I can look at it though:

Either it warms up above freezing, so I can do all this outside on the ground, or it dries out enough I can drive this behind my shop to the 11' door back there and drive it in. Neither seem to be happening.  N:(
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: Rickf1985 on February 10, 2016, 10:01 AM
OK, I have been thinking all along that the tag was the problem. D:oH! D:oH! D:oH! D:oH! D:oH!

I just went back through the pictures from Cook and the factory and Itasca and now I have a grasp on the system and how it works. The link that you guys keep referring to is ONLY to stop side to side movement. The bushings in that link will twist fore and aft. They will not like it one bit but they will twist. Looking at the picture from Cook at how that link is bolted in I would be sure to check the attaching bolts to be sure one or both has not broken. It is not designed to go that way. The way the cradle is designed the weight of the coach is carried by the lower cradle through the side links with the leaf springs on top of them. The lower cradle "should" be self centering due to the weight of the bags pushing down and the fulcrum effect from the side links. It appears that the side links have been jammed forward and possibly self tightened the bolts as they did or just plain rusted into that position. You need to get a good bit of the weight off of that axle and deflate the bags and then you should be able to put a ratchet strap between the two axles and pull the lower cradle back into position. I would put a liberal amount of penetrating oil on the pivot point on the drop link and try to loosen that bolt, that would help. Do not pull so hard you start to move the rearward axle forward, it should not take a whole lot of force to get that back into position.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on February 23, 2016, 02:11 PM
Hi all,


Over the course of last Sunday, I managed to replace all my tires on the RV. While I was doing this, I had access to the entire system, so I set to work. The center link area was fine. No issues with how it is set up that I can see.


I wound up using a Porta-Jack (what a lifesaver) and with the base sitting on the drive axle, I jacked the cradle back until it was in the proper position. I then tightened the side bolts down with an impact to about 180 ft. lbs to keep it from swinging forward again, unless I bottom out on a stump or something.


Now I seem to have another issue with it, one that likely only I will have an answer to.


It does not air up. None of the valves on the tag axle were messed with while doing any of this, nor while changing the tires. I put 110 PSI in the air tank, and the valves did not open. I was not afraid of damaging the air springs, as the valves would taper off/close the added air to the springs as the rig raised itself. Usually around 60 PSI or so before I would hear the valves open and send air to the springs, but nothing this time. It may simply be at 'ride height", I don't know. The tag axle tires don't tip in at the top like the old ones did before. I did take it for a 15 mile spin or so, and it looked like the bags had a little air in them when I parked the rig, but not enough to noticeably raise the ride height. I think this weekend I will try raising one side of the tag axle up in the air with air in the holding tank, to see if it will add air to that side of the RV. If not, then a problem has arisen somewhere. At least the cradle is where it is supposed to be now; that makes me feel better.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: cook elandan on February 23, 2016, 03:32 PM
87, in my pictures, i have 90psi in the air bags. if you want to use as a reference for how high that might inflate. I think that there is a short delay in the linkage with the tag on add/remove air in the bags so that they are not adjusting all the time.  Does your tank hold air.   
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: 87Itasca on February 23, 2016, 04:02 PM
Before when they were tilted, the bags inflated no problem, the coach just never raised more than an inch or so because of the extreme angle which they were tilted. They do nothing now. The air remains in the tank @110 PSI. I have a slow leak somewhere I need to sort out, but I want to just get the system to function right now. Then I can work on the small leak. The air springs were replaced in 2003, and don't have more than a couple thousand miles on them. There is no air going to them at the moment.
Title: Re: '87 Itasca 37RQ, Air Suspension Problem
Post by: cook elandan on February 23, 2016, 06:09 PM
87, Maybe the PO might have adjusted the valves to a point and now that you have the tires and axle back where they should be the valves are closed.  I have disconnected my adjustment rods, they only had a cotter pin to remove and then i  moved them by hand, that way i was able to see the movement of the valve and bags.  if rusted a little maybe spray with some pb blaster on it.