the bulkhead

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the bulkhead

August 06, 2015, 08:39:57 pm

over the last four days I have been repairing my rear bulkhead. I drilled 1 3/8 access holes 2 and 3/4
inches from the angle iron. I then removed all 18 rolok bolts, and drilled them out to 3/8 , and through
bolted them with 3/8 #5 3" plated bolts and double nutted the bolt with a large washer. the access holes
were then plugged with heyco plugs.
I had noticed a couple of years ago that I had one bolt head missing, a month ago I noticed 2 more missing.
my bulkhead was straight with very little surface rust on the angle iron. when I started to remove the bolts it
became apparent that my bulkhead had a problem. several more heads sheared of with very little pressure.
only 4 of the 18 came out whole. every bolt was rusted where it passes through the angle iron.
my coach has spent the vast majority of its life, either in the desert south west or at home on Vancouver
island in the garage. I was under the impression that my coach was an unlikely candidate for bulkhead separation
because of the conditions my coach lived under. I also believe that putting a torque wrench on them may give
you false results, how would you know they were torqued or just rusted in place like so many of mine were.
it is a very nasty frustrating job removing the bolts.

Re: the bulkhead

Reply #1 – August 06, 2015, 09:05:29 pm

Wayne,

Good job.

Still need to use undercoating to seal around the bolt heads. This will keep water from wicking in the threads and getting to the bulkhead square tube.

Re: the bulkhead

Reply #2 – August 06, 2015, 09:18:13 pm

Wayne,

Yes, exactly my take on the testing with a torque wrench. Gives a false sense of security.

You did a nice job. I like preparing both sides of the angle iron, spray galvanizing both sides before painting and use a corrosion resistant fastener to bolt it down. I don't have them done all the way across but when I finish, I will loosen a few at a time, place a large stainless washer between the angle iron and the tin/rectangular tubing and torque it back down again. I like the idea of letting the back side of the angle iron dry out rather than trapping moisture there.

Yes, good to be able to seal the tubing so water can't get into the tubing.

Pierce

Re: the bulkhead

Reply #3 – August 06, 2015, 09:28:35 pm

Pierce,

Not sure I agree. Look at the broken bolts. How many of those would have held to even very minor torquing? The VAST majority will either twist out with very little torque (broken where they first screw into the box beam) or hold torque.

If broken before exiting the 1/4" angle, "Bubba" got loose on that one. The angle should be over-drilled so that the Rolock starts torquing in the box beam, never on the angle. I have only inspected 2 Foretravels where the angle was not over-drilled-- what a mess.

Re: the bulkhead

Reply #4 – August 06, 2015, 09:36:38 pm

Wayne how long did it take to do the bulkhead?

Re: the bulkhead

Reply #5 – August 06, 2015, 10:18:24 pm

Nice write up!

How did you get the broken roloks out, and how difficult was that?

What direction did the broken roloks com out?

Re: the bulkhead

Reply #6 – August 06, 2015, 10:47:09 pm

I have every intention of undercoating, but the first 4 bolts on the passenger side ended in
what looked like wet mushy sawdust. I will deal with that mess when I get to yuma in the fall.
several in the middle were in blue dry foam insulation, and 5 on the drivers side ended in a box
beam with no insulation. the job took 4 six hour days.
as far "as how did you get the bolts out" most were double nutted from the access holes and
came out the access hole, several were beaten hacked drilled and beaten again. the ones in
the box beams were cut off with a hackzall and removed from the access hole. I found easy
outs are not up to the job. just about every bolt presented a different problem, but with
persistence they all came out.

Re: the bulkhead

Reply #7 – August 06, 2015, 10:58:20 pm

Wayne, what was the condition of the bolts behind the wheels on both side? Did they have the most rust/broken? I took out one on each side a couple of years ago on our coach and found them to be as new almost, with no rust showing. I figured if they are like that then the rest would be fine, but did not try to torque any to find out!!
With the pit now maybe I should test them all- not sure/chicken maybe??
JohnH

Re: the bulkhead

Reply #8 – August 06, 2015, 11:01:18 pm

The passenger side ones may have been comprimised because of water bay leakages over time, even road water getting in that bay.
What kind of condition was the (seeable) box section like for rust etc?
JohnH

Re: the bulkhead

Reply #9 – August 06, 2015, 11:27:32 pm

Brett,

I had several where the bolts had broken but were still in the angle iron. They were frozen in position and took quite a bit of effort just to turn them even though they were broken. Others just popped out earlier and were missing. The torque wrench worked OK on some where I loosened them first and then re-torqued them. They did all fail at exactly the same spot.

The concern was the huge amount of rust on the backside of the big angle iron when the front looked perfect. If I felt I could seal the area after cleaning and priming, then I would undercoat the area. My worry was moisture getting in immediately above or traveling down the angle iron or even down the backside of the two vertical supports.

Pierce

Re: the bulkhead

Reply #10 – August 06, 2015, 11:31:41 pm

"first 4 bolts on the passenger side ended in what looked like wet mushy sawdust". On our coach, also a mostly southern dry climate coach, the discovery of the black, wet, moldy sponge like wood remnants was what started my nearly two year bulkhead "adventure". I believe that is indicative of leaks from within the utility compartment. Hopefully, the metal that has been in contact with the wet wood isn't as compromised as it was on our coach. There are many penetrations through the fiberglass skin in the utility compartment as they came from factory. Any screw not sealed or has come loose can and will let water to the space between bottom and top skin of the basement. The wood holds the water like a sponge. I replaced all of the wood with ¼" aluminum plate.
Don

Re: the bulkhead

Reply #11 – August 07, 2015, 12:33:37 am

don
perhaps because you have seen the whole thing dissected, you might know what the purpose of all that wood,
if that's what it is, is doing in there. do you have any suggestions how to deal with the mush without
dismantling the coach?
and I agree, about the water being spilled in the above bays being at least partly responsible
for the water intrusion.
I've been rv ing long enough to know, anybody who says they have never filled that area with water may be fibbing.

Re: the bulkhead

Reply #12 – August 07, 2015, 03:16:27 am

Wayne,
When I had the entire basement framing exposed, it was clear to me that the framing plan was done in such a way that the fresh tank could be towards the rear as it is in our coach, or the fresh tank would be towards the front and the waste tanks towards the rear. It all depends on the floor plan and where the toilet is etc. The position of the partition between the waste and fresh tanks was moved to accomodate the fact that the waste tank part of the utility compartment is wider than the fresh tank side. The framing allowed for the sewer hose and shore connection notch to be placed either to the left next to the storage bay or in the center of the the utility compartment just to the right of the partition. that is why the framing is doubled up or sistered in several places so FOT could use the same plan and just cut out the piece on the outside edge where the notch ended up.

I will attach a picture that shows the basic utility bay framing from when I was near the beginning of mu bulkhead project. In this picture, I have already remove the tanks, water heater, pump, insulation, and started cutting out compromised metal. The outside edge or sill on the driver's side has been cut out and held it in place with magnets so I could brainstorm what to do next (and of course because I forgot to take a picture before I cut that section out). The obvious gap on the right side is from some metal so badly rusted, that I didn't bother to try and include in the picture. Also apparent in the picture, the you can see where the sewer notch is in our coach. To the right you can see the place where it would be if the fresh and waste tanks were reversed and the partition was moved about six inches to the left to accommodate. You can tell that by the fact that the outer edge of the compartment just has an inch and a half piece of angle iron and no square box tubing for the 6" or so where the notch would be. Hard to explain in words, but hopefully the picture makes it clear. The purpose of the the wood is to support acquires such as power cord and hose reels on the street side, and water pump etc. on the curb side. The wood is in four places along the outer edges (two street side and two cub side) instead of insulation. So with either tank set up, there would be wood where the water pump would go, or where the reels would go (if equipped). I hope that makes sense!
Don

Quote from: Wayne Macauley – August 07, 2015, 12:33:37 am

don
perhaps because you have seen the whole thing dissected, you might know what the purpose of all that wood,
if that's what it is, is doing in there. do you have any suggestions how to deal with the mush without
dismantling the coach?
and I agree, about the water being spilled in the above bays being at least partly responsible
for the water intrusion.
I've been rv ing long enough to know, anybody who says they have never filled that area with water may be fibbing.

Re: the bulkhead

Reply #13 – August 07, 2015, 04:11:14 am

I just replaced all the bolts in my rear bulkhead. I posted pictures in another post that show the broken/rusted bolts. All were replaced with grade 8 zinc plated 3/8" x 3" through bolts with a 1/8" steel backer against the box beam (inside).
I cut out a access area in front of the box beam to get a good look. I still have not "button up" the cut out area.
I'm still on the fence as far as using a sealant over the bolt heads.
My fear, trapping moisture.
I don't know for sure that I will be able to totally seal the bulkhead from all sides. I already decided that I would NOT run the solid insulation up against the box beam when I reseal the area, I don;'t want any leakage to be trapped next to the box beam.
I have the same fear with the undercoating. I see no way to seal the actual angle iron/box beam butt joint. Sealing just the bolt heads and outside of the angle iron doesn't seem worth it. I would rather see a way out for any water than trapping it in pockets.

I did rust coat the metal and then paint the area before bolting the bulk head together.
Is my thinking on this flawed?

Re: the bulkhead

Reply #14 – August 07, 2015, 08:37:40 am

Years ago we removed most of the plumbing connections around the water pump area, removed expansion tank & bathroom cabinet water fill hoses, & ran new hoses to water manifold, hot water tank and from fresh water overflow. During this re-do when the original drain hose's large hole through the floor was empty of hoses, we learned we had the 'in the floor wet wood mush' problem. Our solution at that time was to use a bent coat hanger wire to scrape out all the mush into the large hole and let it fall to the ground.

With the help of air dryer, etc we let the space dry out. And then we made many spacers from short cut pieces of PVC pipe that were put between the upper and lower fiberglass layers and moved about using our coat hanger. We then used some spray foam in the space a little at a time so all foam expansion would be horizontal. When the foam expanded out the water drain hose hole we knew we had the space covered.

All holes and edges in the water pump area floor were sealed (GE Silicone II) and everything was placed back without any screws holding plumbing to the floor. Flexible plumbing hoses keep things in place without fasteners and when our water pump acts up, we just reach in and pull it out without having to remove any hoses.

We also have water alarms in the water pump area and under the water manifold to let us know if things are wet. Alarm's sounder is up in living space so we can quickly hear it. To keep any expansion weeps out of the bay, we ran a hose from our propane hot water tank temp-pressure relief valve down through the floor along with the other drain hoses. We keep a paper towel sheet under the water pump and hoses and check it to learn that all things are staying dry.

Re: the bulkhead

Reply #15 – August 07, 2015, 09:52:54 am

Lon,

Sounds good to me. With some coaches, the angle iron area may not be at risk as much as water leaks in the tubing area on the belly. I don't like the idea of water being trapped in the insulation and gradually eroding the steel. Barry has been proactive with the potential problem.

Pierce

Re: the bulkhead

Reply #16 – August 07, 2015, 10:00:32 am

I'm not going to undercoat anything. Instead, I'll just paint with Rust Bullet or similar paint.

Re: the bulkhead

Reply #17 – August 07, 2015, 10:28:10 am

Quote from: krush – August 07, 2015, 10:00:32 am

I'm not going to undercoat anything. Instead, I'll just paint with Rust Bullet or similar paint.

If you still have Rolocks, please undercoat. They have serrated/raised area that acts as lock washer. This "stands off" the angle beam and allow water to wick between the serrations.

And, indeed, if the the angle is not overdrilled (as it should be), indeed the Rolock could be torqued/broken in the angle.

Remember, the angle should be overdrilled such that the Rolock torques ONLY on the two walls of the box beam.

Re: the bulkhead

Reply #18 – August 07, 2015, 10:41:49 am

Quote from: wolfe10 – August 07, 2015, 10:28:10 am

If you still have Rolocks, please undercoat. They have serrated/raised area that acts as lock washer. This "stands off" the angle beam and allow water to wick between the serrations.

I agree with you. I need to replace rolaks though.

Re: the bulkhead

Reply #19 – August 07, 2015, 12:53:44 pm

I contemplated leaving a gap for moisture to get out, but decided to seal the area instead. Since I had full access to the area from above as well as below, I caulked the the top and bottom seams of both sides of the compartment. On the top of the seam, there is a bead of caulking between the Por-15 coated metal of the compartment framing and the vertical sheetmetal of the bulkhead in the compartment. Then there is another bead of caulking between the top of the fiberglass skin and the bulkhead. And finally, there is a bead of caulking between the fiberglass skin of the basement floor and the fiberglass covered sheet of insulation that lines the inside of the bulkhead. I also minimized penetrations through the bottom skin as much as possible and screws that penetrate are 10-32 stainless machine screws tapped into the aluminum plates which replaced the plywood. Although the plywood was in just the four larger sections nearest the sill on the curbside, and just inboard of the notch framing on the street side, I elected to put the aluminum plates under the basement floor skin wherever it wouldn't be under the tanks. There is rigid polyurethane insulation under neath the plates and filling all the voids. At any rate, I plan on adding a drain tube on either side of the compartment because I have realized that water will end up on the basement floor in that compartment in spite of my best efforts to prevent it

However, I believe that the seal between the basement floor and the area beneath is fully intact... The following picture is the area after coating but before the insulation was installed. You might notice that I added a few diagonal braces and other misc. pieces along the way...

Don

Re: the bulkhead

Reply #20 – August 07, 2015, 01:12:50 pm

The problem isn't that water gets in places. The problem is they didn't PAINT ANYTHING at the factory. Or did a lousy job.

Re: the bulkhead

Reply #21 – August 07, 2015, 01:23:54 pm

The framing was painted from the factory... looked like red primer to me. I am sure that had it been powder coated after welding, it would have fared much better. But as I see it, as long as water can get in but not out, there will eventually be rust. It was my hope in going through the rigors Por-15 application process that I could minimize the chances of the damage reoccurring, at least in my lifetime!
Don

Quote from: krush – August 07, 2015, 01:12:50 pm

The problem isn't that water gets in places. The problem is they didn't PAINT ANYTHING at the factory. Or did a lousy job.

Re: the bulkhead

Reply #22 – August 08, 2015, 12:13:43 am

This thread is very timely. A few days ago I relocated our overflow to the floor. To my surprise the area I thought would be foam was actually a wet mushy moldy plywood. Glad to see I'm not the only one. We had leaks in this bay a long LONG time ago. It's clear that it's well sealed from the bottom and doesn't drain. Once we get to Florida I intend to deal with the bulkhead as well as the mushy wood. For now I sealed it in, buried my head in the sand and said "this isn't happening".

Re: the bulkhead

Reply #23 – August 08, 2015, 12:16:54 am

For the record my opinion is that when it comes to water, Foretravel and coach builders in general take a terrible approach to it. The idea that you can seal water out is insanely foolish. It's not a question of if the roof, tank, plumbing, etc will leak but when. Choosing composite materials, sloped floors, drains, etc would go a long way to preventing these problems.

I think that everything would work a lot better if they adopted the ideal the car manufacturers learned after "sunroofs of the 80's". In my 96 BMW the sunroof is surrounded by a tray. The seal is not expected to hold up perfectly and on all 4 corners of the tray are drain hoses. Such drainage areas, trays, etc on the roof with drain tubes would be a great idea.

Re: the bulkhead

Reply #24 – August 12, 2015, 04:11:44 pm

Well I was about to turn the coach around to work on the other end and thought "I gotta check these B'hd bolts"
So after testing them all I found 2 in the middle that the heads + about 1/4" of thread came right out!!! Sh-t I thought, Bubba has been at work as Brett said.
So out with the hole saw between them and once foam was out the tube is like new

, and after drilling a 3/8 hole the walls of tube are as new, no rust just nice clean shiny shavings on the drill bit I used the same bolt method as Wayne plus lock washer and sealed it all up--forget that area now I feel better and it tok me (once I had drill bits etc etc out) about 10 mins to FIX AND CLOSE UP. This is the benefit of my pit. I reckon the whole job to replace every bolt on one end if needed just drilling new and bolting would take 2 hrs. Trying to remove each broken Rolock would be a lot longer I would think.
No rust or moisture at all visible so now I feel fine.
JohnH

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