Bulkhead failure years and Torque Test

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Bulkhead failure years and Torque Test

April 28, 2017, 06:32:25 pm

To continue my education on bulkhead failures, the latest info.

Some continue to suggest that torque testing of the bolts will indicate that the bulkhead is secure.

That is not true. You will note that the bolts were secure in this bulkhead failure example, which is an example of extensive failure. Testing the bolts alone would lead you to assume all is ok.

Some have asked me if such failure is limited to coaches of 2001 and prior. No. Failures have been seen in years to and including 2004 of which I am aware plus a 2005 which may be an outlier.

Others of you may know of later years?

Re: Bulkhead failure years and Torque Test

Reply #1 – April 28, 2017, 07:35:12 pm

Quote from: Michael & Jackie – April 28, 2017, 06:32:25 pm

Some continue to suggest that torque testing of the bolts will indicate that the bulkhead is secure.
That is not true. You will note that the bolts were secure in this bulkhead failure example, which is an example of extensive failure. Testing the bolts alone would lead you to assume all is ok.

You hit it on the head. Others are in denial. Neither the design nor the lack of a preventative coating changed so you can't expect the outcome to be any different for later coaches if the coach is exposed to road chemicals or has a water leak. This is why it's so important to do a complete inspection before purchasing a used coach and then take care of it. Driving in harsh winter conditions is just asking for problems down the road. Road salt is a RV's arsenic.

Pierce

Re: Bulkhead failure years and Torque Test

Reply #2 – April 28, 2017, 07:45:10 pm

Guys,

Newbie question....

If one has a unit with solid bulkheads -- no damage -- is there a consensus on preventative treatment and maintenance? I've been reading bulkhead inspection and repair threads like crazy but am not finding a lot in my searches about what to do with a healthy coach.

TIA,
Mark

Re: Bulkhead failure years and Torque Test

Reply #3 – April 28, 2017, 08:18:06 pm

First be dang sure it really good inspection and if you were telling me it so I would ask how you know.

Preventative....no water. Think your model year how get water in there. Tank overflow can happen in yours or is such routed outside? Missing screws, bolts? A loose fiberglass skin joint at the seam. But an odd place I have seen twice was a very small gap in the seam of metal and fiberglass at the utility drop flap door. Water seeped in there.

Pay attention to your utility bay fresh water hose. People have seen it siphon water back into the utility bay of just residual water drain out of the hose into the bay and then from there into the bulkhead area, on mine it could get in around the sewer drain pipe

I imagine other ideas and I will post another new option shortly

Re: Bulkhead failure years and Torque Test

Reply #4 – April 28, 2017, 08:33:03 pm

Mike,

I'll make note of those places to check for water intrusion. If -- and I know it's a big if -- the bulkheads are solid, what are best practices for treating the bare metal to prevent future issues? Paint, undercoating, other?

Thanks,
Mark

Re: Bulkhead failure years and Torque Test

Reply #5 – April 28, 2017, 09:42:56 pm

I totally agree, torquing the Rolock bolts alone is not all you need to look at when evaluating a bulkhead.

It is ONE of the several things that you need to do/evaluate.

Additionally, one needs to look closely for signs of RUST JACKING-- swelling of the basement floor under the box beams.

One also needs to look closely for any sign of water currently present in the basement laminate-- pressing on the under side of the basement often reveals trapped water if there is any present. But, as with torquing the Rolocks, absence of water right at inspection time is not in itself a guarantee that all is well.

Re: Bulkhead failure years and Torque Test

Reply #6 – April 28, 2017, 09:49:48 pm

Mark,

The problem is that 95% of the steel susceptible to rust is hidden where it's hard to get to. Check Don's old posts with great photos to get an idea of where the steel structure extends to. Crawl under and check the big angle iron. Sure, you can paint it but the rust is behind it and in the case of severe corrosion or a water leak, may extend well into the rectangular tubing. To do a complete inspection, you need to spend some time and money. Removing a few Roloks and checking their condition is a start. A borescope into the tubes can also give a clue. The Roloks were the wrong fastener from the start and in the event the need to replace some, a more suitable fastener should be used. Undercoat would seem to at least be a partial solution but it could actually make it harder for moisture to find it's way out. Once you take a look at yours and then do the research here, you will gradually be able to put together possible problems along with their solutions.

Pierce

Re: Bulkhead failure years and Torque Test

Reply #7 – April 28, 2017, 10:07:38 pm

Quote from: Michael & Jackie – April 28, 2017, 06:32:25 pm

To continue my education on bulkhead failures, the latest info.

Some continue to suggest that torque testing of the bolts will indicate that the bulkhead is secure.

That is not true. You will note that the bolts were secure in this bulkhead failure example, which is an example of extensive failure. Testing the bolts alone would lead you to assume all is ok.

Some have asked me if such failure is limited to coaches of 2001 and prior. No. Failures have been seen in years to and including 2004 of which I am aware plus a 2005 which may be an outlier.

Others of you may know of later years?

This would not be hard to miss on any inspections... When inspecting it goes better with your eyes open..

The rust and cancer that is on that metal has been happening for a long time.. Not something that happened in a year or 2. Looking when doing an inspection would find this and if its peeling from the rust it needs replaced. Spray wax would help in this area. Every year maintenance would keep it clean and newish

That stuff looks like it sat in the water/salt for 5 yrs.

My 2002 is in great shap but has not been out east much or where they salt the roads/wet conditions

Re: Bulkhead failure years and Torque Test

Reply #8 – April 28, 2017, 10:14:29 pm

Not to steal Mike's thunder.........

We also had our floor structure repaired/replaced and were in the shop while he and the Gal were there and may have some insight on this issue. I am by no means an expert.

I do not think that anyone knows what if any corrosion resistant coating FT applied when building the coach. If so I would be pleased to know the name and specs.

It is very difficult to "eye ball" the problem. The only way to know the actual condition is to verify that this basement floor structure is corrosion free. That would be done through visual inspection.

I do not have to make that decision because a very sharp and experienced guy saw a possible telltale that required further inspection. A previous inspector two days earlier said I should tighten screws and get the bulk head painted. This was a courtesy inspection, that they no longer perform - I think.

About 18" of the floor pan in front of the wheels was cut away on our Ol Girl to visually inspect this metal floor structure. We required that that section, which was more corroded than Mikes's, be cut out and re fabricated. It was replaced using like diameter but thicker wall steel tubing. I did not ask the grade of the square electrical welded tubing that was used. Should have though. It appeared to be Mild Carbon steel commonly used in welding shops and it appeared OK to me.

If I were passing through Nac I would think seriously about having it inspected. I think the cost of the inspection is $300/$400.00 but you would "know" condition. I do know, at least one person that had his 2003 inspected and was OK. I have heard of many others that did require some repair. Some worse than others.

I look at this issue as a maintenance issue and must be addressed just like oil, trenny fluid, frame lub and other stuff we do. If I were buying today I would consider the cost of this inspection in relationship to the cost of the coach. Again I would have it professionally inspected and pay the inspection fee - gladly.

In support of Mike's comment re: Torquing the bolt heads on the bulkhead itself will not verify corrosion or lack there of 3" away. It can be corroded to the point where it will no longer support the weight required and something bad may happen.

Just my $.02.

Re: Bulkhead failure years and Torque Test

Reply #9 – April 28, 2017, 11:59:50 pm

DavidS...this is often not or even obvious, especially to untrained eye or even those thinking they are.

To Scotts comments, he had just bought the coach from a very experienced and diligent owner. I would never have questioned there being a problem. Even then experiences owners may not see this versus a trained inspector,

As fir Scott, as he noted, I happened to notice what I thought was a problem, I hated to tell Scott, it being new to him, and maybe I was wrong. And so the mechanic who i asked reviewed it said yes, it a problem.

Scott's repair came immediately after mine. Of mine I had posted photos. Those generated enthusiasm for the Risch-Thomas repair method, with greatly reduced costs over a prior repair method, but also a question or concern too. Scott used his repair to further explore the repair techniques and welding, coating, etc. I was grateful for his analysis and reassurance we were doing the right thing...after all this was a new technique. I always just trust Risch. And Risch is patient of my curiosity.....how do you butt weld tubing, for example....and my wanting things done right.

All of that was in a thread I began to bring this topic to the attention of our members, something to think about, watch for. It has become the first chapter. More chapters have been added, with contributions by many and especially Scott. This damage, if it exists is, as Scott says, is much easier, less expensive, to manage if caught early.

MOT has now repaired eight of these and virtually all were unsuspecting. as Scott said, others had even inspected his before. Ditto for me, within the year before mine was found in the extra insoection I hired at Annual, I had another shop tell me it ok.

The reason for the photo i put here, the shop I used, MOT, keeps in touch trying to continue my education. They wanted me to see the worst they have seen on the very rear attached tubing metal......if you look closely, and I should have pointed it out perhaps, there is virtually nothing left holding it together. Almost all of the small connecting tubing is gone, rusted out. But the bolts are still tight.

Pierce also makes a good suggestion and if I knew nothing of the condition in there, I would try to apply his idea of a scope. I think another member suggested to remove the fuberglass covering, inspect every five years. It is not a huge deal if caught early enough but if not the repairs later can be expensive.

My goal.....call attention to check it, build a reference base of Bulkhead Repair threads, people you can call like Scott, Pierce, Risch

Re: Bulkhead failure years and Torque Test

Reply #10 – April 29, 2017, 12:22:03 am

Thanks again to Mike and Keith R.

While at MOT and undergoing our experience a scope was discussed as a possible detection method and it was thought that 10 to 14 holes might have to be drilled, and patched, to see all of the spots that could be effected. It was also discussed that a scope could be used as an indicator and if corrosion was found in one or more holes, then a further inspection could be completed. From a cost standpoint it was felt that it would be less expensive to the motorhome owner to cut that bottom panel material across the width and by about 18" and reseal with new material after the newly fabricated structure was coated with a corrosion preventative. I have no idea how often this inspection should occur. I guess 5 years might be adequate.

This is not a pleasant situation for the owner or the shop but should not, in my opinion, scare anyone away. The repair, in most cases are less than a set of tires.

It would be interesting to know how many units were inspected by FT and MOT and how many required repair. There sure was a flurry when we were there.

Re: Bulkhead failure years and Torque Test

Reply #11 – April 29, 2017, 12:22:56 am

Sorry.. maybe my response came out wrong. That is a lot of rust and I cant see how it was missed in any inspection. I could understand if it was seen and put off for a little bit but I would have been tripping out if I found that. If you look at the rolled edge of the tube its rusted pretty good so if and when looking at it there should have been earlier signs. If a piece is needing replaced just cut it out.. rebuild and use a sleeve at connections and weld it back.

Also if the metal was bad it would bow or twist at some point?

Wasnt trying to pick on anyone .. just saying if someone checked it and I had paid for them or even if they volunteered for free.. and didnt see it id be a little more than upset.

Re: Bulkhead failure years and Torque Test

Reply #12 – April 29, 2017, 01:53:15 am

It was hard for me to believe that all that corrosion was covered by a relatively clean underbelly pan.

Our corrosion was not observable from under the coach. There were no red streaks or stains. There was one small ripple in the pan material where it is screwed into the "Bulk Head". The deviation from flat on this single ripple at the edge of the pan was no more than .064" in height and <1" in length. At MOT there were a number of employees that came by to see the extent of the corrosion. Many had looked under the coach before the pan was cut back and when the fabrication was attached and all of the other stuff they did.

I have confidence in Keith R's abilities and ethics and would follow his recommendation(s) regarding "proper" inspection procedures.

Re: Bulkhead failure years and Torque Test

Reply #13 – April 29, 2017, 02:01:39 am

I know there are many engineers on the Forum. I know that x-ray is used in determining structural

problems. Would it be possible or cost effective to use this as a way to inspect these frames on

the coaches?

Carter-

Re: Bulkhead failure years and Torque Test

Reply #14 – April 29, 2017, 02:08:38 am

Ultra sound? Interesting,

Re: Bulkhead failure years and Torque Test

Reply #15 – April 29, 2017, 04:16:57 am

Quote from: Texas Guy – April 29, 2017, 02:01:39 am

...............Would it (radiography) be possible or cost effective to use this as a way to inspect these frames on

the coaches?................

Carter,
In a word ........ No
In a few words ........ There are dozens of easier ways to detect bulkhead damage than to non destructively examine (NDE) using radiography, where the metal of interest, ideally:

needs to be directly between the radioactive source and the film that is recording (looking for) any metal defects

needs to be solid metal, although consistent gauge tubing is "readable"

The area/volume of space on either side of the metal must be open and accessible, for a "source" on one side of the metal object of interest , film on the other. Therefore, the bays would have to be completely stripped of interference (tanks, reels, trays, tubing, etc.).

even then, with all interference removed, the film size, development of the film and film interpretation would be prohibitive, cost wise, not to mention that one needs be licensed to possess and use the source, which automatically adds cost.

[/list]

So if there are any indications of a potential problem being hidden between the upper and lower sheets of fiberglass sheathing for the basement framework (indications such as rolocks that fail torque, missing Rolock bolt heads, rust stains at any of the sheathing bolt penetrations, rust stains at any of the through bolting for the reels, propane tank, basement bulkheads, unwarranted swelling and/or rippling of the sheathing, water or diesel fuel dripping out of sheathing penetrations anywhere or at the sheathing edge perimeter or trace evidence that it has dripped or flowed in the past, rust jacking at the bulkhead joints, unwarranted waviness in sheathing materials, any waviness whatsoever in the 1/4" bulkhead angle iron, waviness in the body fiberglass on either or both coach sidewall(s) above the rear drive axle wheel wells, etc. etc., etc., to name a few -- and I have NEVER seen a bulkhead rust damaged coach that didn't have one or more of these indications, most coaches that are rust damaged have several of these indications and many have ALL), then it is easier to just remove some of the basement outside (bottom side) sheathing and see what you have got, up close and personal. That is what MOT and Extreme have been doing for some time, as they deem appropriate. It isn't a new process, at least since 2009, when I first watched Extreme do it on my 1998 U270, even after I had repaired my rear bulkhead, myself. James felt it was worth a further look and I agreed. James Stallings and Dave R. (MOT) seemed to be in sync, even back then.

Ultra sound NDE would be less expensive but wouldn't work due to the lack of consistent coupling between layers of dissimilar materials. Even if the coupling was perfect, the echoes produced would take a great deal of talent to analyze effectively.

HTH,
Neal

Re: Bulkhead failure years and Torque Test

Reply #16 – April 29, 2017, 07:19:04 am

Ours was done by Keith three weeks ago. We had no major issues but he did perform a reseal of the bulkhead. Cleaned out the joint with a modified sawsall, coating applied, rebolted with stainless using method described by Brett. Finally applied sealant and caulked. Just a bit over 1,000 but a lot of peace of mind. This was one I thought I could do and glad I did not after I saw their entire process.

Re: Bulkhead failure years and Torque Test

Reply #17 – April 29, 2017, 09:24:30 am

Quote from: DavidS – April 29, 2017, 12:22:56 am

Sorry.. maybe my response came out wrong. That is a lot of rust and I cant see how it was missed in any inspection. I could understand if it was seen and put off for a little bit but I would have been tripping out if I found that. If you look at the rolled edge of the tube its rusted pretty good so if and when looking at it there should have been earlier signs. If a piece is needing replaced just cut it out.. rebuild and use a sleeve at connections and weld it back.

Also if the metal was bad it would bow or twist at some point?

Wasnt trying to pick on anyone .. just saying if someone checked it and I had paid for them or even if they volunteered for free.. and didnt see it id be a little more than upset.

David,
Perhaps I am reading something into your comment that is not there, but:
Not a single bit of that steel is visible-- it is all sandwiched/encapsulated between the FG floor to the basement and the FG underside of the coach.

The visible signs would be rust jacking, broken Rolock bolts, rust stains or degradation of the "seam" between the 1/4" angle and the box beam, etc.

Re: Bulkhead failure years and Torque Test

Reply #18 – April 29, 2017, 10:25:31 am

DavidS, Scott and Brett exokained better than I or perhaps my original thread photos why you could nit see anything. I have a whole library of these coach frame photos, varying stafes of not just rust but totally failed tubing. I think the coach standed near Corpus a couple of years ago was due to structure failure from such that let the axle shift on one side.

David, on one coach I was shown a pretty small variation in a wall seam that Mr Risch said was caused by or illustrared how failing along the bulkhead was now pulling on the side of the coach bay. Now the problem grown beyond what we dealt with! Pro inspection is vital.

I like Scott idea, he has posted it before, probably best and only way is to open it up and look, replace the cover, inspect again in five years. I think, for me, only way at this point.

And George approach above....hire that done by Keith Risch and Steven. Small cost of insurance.

We are all learning....

Re: Bulkhead failure years and Torque Test

Reply #19 – April 29, 2017, 11:26:59 am

Perhaps a standardized method of inspection/repair could be found. Possibly using a 1/8" aluminum diamond plate across the belly of the coach from the bulkhead forward a few feet. Secured with stainless/galvanized fasteners and sealed with a vinyl type gasket so water could not migrate up. Use a removable closed cell foam for the insulation and coat the steel tubing with rust resistive primers/paint. The big angle iron could be spaced away possibly 1/16" to 1/8" from the bulkhead sheetmetal by a number of large washers so water could not collect, corrode the fasteners and weaken and break them from rust jacking as Brett mentioned. The back side of the angle iron could be de-rusted and primed at the same time. This way, an inspection could be quickly and easily done and any problems quickly caught. Some thought would be also needed on the wet bay so any leaks could not find their way below but would drain out instead. The same design could be repeated for the front bulkhead.

New, larger 3/8" stainless or galvanized fasteners could then be through bolted to the opposite side with the appropriate washers/nylocks. I am part way through installing 3/8" 316 stainless on ours. The specified torque (and I tried grade 8s without a problem) will not deform the rectangular tubing unless it has been weakened. (and no, there is almost zero electrical potential between the steel and stainless) When new, the existing number of fasteners across the bulkhead bottom is enough to pull a locomotive but with rust jacking and hydrogen embrittlement, the strength drops to a tiny fraction of what it was when new.

A preventative maintenance program would also be needed to minimize future damage from road chemicals. As I said before, in harsh German winter weather, we stopped at the car wash every night on the way home for a undercarriage rinse. If you are going to drive on chemically treated winter roads, you can't just put the coach away until the next time you use it and not expect long term damage.

Pierce

Re: Bulkhead failure years and Torque Test

Reply #20 – April 29, 2017, 11:32:40 am

Hate to use up a post just to say great idea Pierce, but I would buy that!

Re: Bulkhead failure years and Torque Test

Reply #21 – April 29, 2017, 12:06:14 pm

Quote from: Michael & Jackie – April 29, 2017, 11:32:40 am

Hate to use up a post just to say great idea Pierce, but I would buy that!

Thanks! I don't think any post that can get everyone on the same page or at least thinking about it is a waste. Since we know we all have a potential problem, it would be good to have a master plan. Lots of good brains on the forum and ideas to go with them! Wish I could do 3D illustrations as that's the way I learn best. Never have been good reading manuals. Guess that's the ADHD.

Pierce

Re: Bulkhead failure years and Torque Test

Reply #22 – April 29, 2017, 12:37:43 pm

I just meant my saying it is a great idea wastes you time....! It is obvious good without me saying 'tis!

As for 3D, maybe make a cardboard model? Or legos?

I want to reread your idea, hard on this phone, think about the 3D idea...later.

At a baseball game for children with a variety of disabilities, grandson participating, so my emails a bit cryptic as limit my reading time to breaks. Hot now, about to quit

Re: Bulkhead failure years and Torque Test

Reply #23 – April 29, 2017, 01:49:02 pm

Quote from: DavidS – April 28, 2017, 10:07:38 pm

My 2002 is in great shap but has not been out east much or where they salt the roads/wet conditions

Attached is a picture I took of one of the towers on the aerial tramway that connected the mine to the mill in Pioche, Nevada.
That steel is almost 100 years old, spent its whole life outside and still retains its original definition having only a slight coating of surface rust. That's the difference between Maine and Nevada. My FT has never ever seen any salt.

We have a Catch 22 situation with our FTs in that sealing up the belly pan doesn't allow water to escape. A perforated belly pan
with duckbills might be the ticket!

Re: Bulkhead failure years and Torque Test

Reply #24 – April 29, 2017, 03:02:49 pm

Quote from: wolfe10 – April 29, 2017, 09:24:30 am

David,
Perhaps I am reading something into your comment that is not there, but:
Not a single bit of that steel is visible-- it is all sandwiched/encapsulated between the FG floor to the basement and the FG underside of the coach.

The visible signs would be rust jacking, broken Rolock bolts, rust stains or degradation of the "seam" between the 1/4" angle and the box beam, etc.

I see what you are saying but

Water is getting in from somewhere and all the water is sitting sealed up in between the fiberglass? would it not leak rust or colored water from somewhere? Bolt heads? screw heads? or it just happens to be just enough water to cause rust but leave no signs? Warpage ? or something? It just seems that one would be able to see something. Thats all I am saying.

Now if it fills up and holds the water where would the water enter from? Or is it safer to say it just happens?

Maybe by loosening the bolts the water would drain so checking a few bolts?

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