Just Noticed Some Front Bulkhead Rust. Thoughts...

Topic: Just Noticed Some Front Bulkhead Rust. Thoughts... (Read 1264 times) previous topic - next topic

Just Noticed Some Front Bulkhead Rust. Thoughts...

September 22, 2024, 08:09:16 pm

Hello Forum Members. I have read and learned a ton from this Forum so thanks to all. This is my first time posting. I have a 2007 Phenix, its Coach 6428. I have known of the bulkhead issue and watched mine very closely. As well I have read not all but numerous threads on this issue on this forum.

I purchased the coach in 2016 from Foretravel and on the PDI sheet of repairs it was noted to reseal front and rear bulkheads and indeed when i picked it up it did seem to have very new black silicone or something of that nature on the joints where the belly pan meets the angle iron if you will. I have put about 100k miles on the coach since purchase in 2016 and have been checking the bulkhead areas regularly and last year I noticed a slight crack in the front seal / silicon etc.. It was barley noticeable and I put it on the list to reseal. Long story short I forgot about it and a year later it has gotten bad enough that it started to separate the under belly from the bulkhead (rust jacking). Shocked it went that quick but it did. This is the front bulkhead I am having issue with. Pic 4 is the passenger side front. No separation just some red streaks. Pic 5a,5b driver side front separation. Pic 6 is opening up the area a little. Okay so my question for someone that knows way more then me. There is no plumbing in in this area of the coach and I am assuming this is water intrusion from road rain, so that leads me to believe mostly likely only the bottom of the framing is effected at this point. The reason I say that is it would be fairly easy to put rust conversion and repaint the bottom of the frame however without major disassembly I can't see how I would get to the sides etc.. So I am hoping at this point I can just put rust conversion the under side and I can get to and reseal bottom panel and move on with life. I understand this is a lot to determine from a couple pictures but just wanted to get some general thoughts on this.

Pic 7 and 8 are of the rear bulkhead where I don't see any signs of rust or cracks in the joint. I took a 2lb ball ping hammer and hit it right where the bottom pan is on the frame and it sounded solid unlike the front where when I hit the hammer there I could tell it was no longer adhered to the frame assuming due to the rust. So fortunately I think the rear is good but obviously I need a little work on front.

Question what is the sealant I should use on this joint? Any other tips or tricks for me. I have seen absolute horror stories on the forums about rusting bulkhead some so bad you could push a screw driver through, but I think I am a long way from that where I am at now but I want to address it ASAP and hope I can reverse this without major repair. Is there anyway to tell from the picture how early you think it is i caught this? Assuming on the rear I can just apply a new layer over the old?

Thanks again to all for your input. Happy and Safe Travels.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #1 – September 22, 2024, 10:31:13 pm

Yes, there is bulkhead damage. You need to pull down the fiberglass underbody to see how far into the center the damage goes.

AND, interesting, looks like huck bolts. Don't recall what year they changed from Rolock's.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #2 – September 23, 2024, 12:11:16 am

Thanks Brett. I will plan to pull back more of the under belly so i can do a more through inspection.

The salesman i bought the coach from was Tyle Fore and he did say this coach had huck bolts VS rolocks but i am not sure when they switched. i believe this was the 3rd Phenix they did. it was finished in Nov of 2006. Assuming Huck bolts were stronger then Rolocks? are they better? Clearly with water intrusion i will still have a problem to deal with!

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #3 – September 23, 2024, 07:40:41 am

Quote from: Bob Hawkins – September 23, 2024, 12:11:16 am

Assuming Huck bolts were stronger then Rolocks? are they better? Clearly with water intrusion i will still have a problem to deal with!

Yes, huck bolts are stronger than Rolocks. But, the bulkhead issue is not really about the strength of the fasteners. It is about the degradation of the box beams in the front of the rear bulkhead and rear of the front bulkhead.

Said another way, having a massively strong fastener securing a rusted out box beam to the front/rear angle beam doesn't really achieve much.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #4 – September 23, 2024, 09:27:16 am

If you look at the where the vertical tubes are spot welded to the sheet metal in your pic #4, I consider this a problem on all Foretravels that were made this way. The sheet metal is also spot welded to the angle iron above where the roloks or huckbolts go through. Every puddle that is driven through throws water onto the top of the angle iron and then can seep down in between the sheet metal and angle iron and starts the corrosion process. IMO, sealing only the bottom just ensures that any moisture that gets in can't get out. Sealing between the spot welds and/or covering the area to prevent the direct spray blast from the tires should have been done at the factory. Any rust repair job should really include sealing between the spot welds unless you live in the desert with no plans to drive in the rain. Driving on salty roads and plumbing or other leaks just compound the problem.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #5 – September 23, 2024, 09:31:06 am

Quote from: Dave Larsen – September 23, 2024, 09:27:16 am

If you look at the where the vertical tubes are spot welded to the sheet metal in your pic #4, I consider this a problem on all Foretravels that were made this way. The sheet metal is also spot welded to the angle iron above where the roloks or huckbolts go through. Every puddle that is driven through throws water onto the top of the angle iron and then can seep down in between the sheet metal and angle iron and starts the corrosion process. IMO, sealing only the bottom just ensures that any moisture that gets in can't get out. Sealing between the spot welds and/or covering the area to prevent the direct spray blast from the tires should have been done at the factory. Any rust repair job should really include sealing between the spot welds unless you live in the desert with no plans to drive in the rain. Driving on salty roads and plumbing or other leaks just compound the problem.

Good point, Dave.

And, the "sealing" can be done with regular automotive undercoating which is available in spray cans. Just mask off what you don't want coated.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #6 – September 23, 2024, 02:45:41 pm

Dave. Great point. I had not thought or realized water could enter so easily from above. Just assume that couldn't reach the bulkhead as i hadn't see any attempts to protect that area. I can fairly easly do this on the front and rear areas. I marked up the photo of pic 4 and attached it here with arrows where i think you are indicating i need to seal that up to prevent water from getting in.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #7 – September 23, 2024, 02:57:21 pm

Yes that sheet steel is just slipped behind those parts you have arrows on and tacked in place. With that calk under the bottom without addressing the top side you have no place for moisture to escape. We have sprayed that area with the arrows with bed liner several times on both front and rear bulkheads.

Mike

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #8 – September 23, 2024, 06:56:01 pm

That is why I did not seal the angle iron, etc as any water splashed up on the vertical tubing will get behind it and drip down and then if it's sealed , it's trapped and will cause rust. And, if the splashed water has any salt in it, the rust will happen much faster.
Pull the white FG covering to expose as much rust as you can and then plan accordingly. Where I needed to, I used all stainless fasteners. Hot dipped galvanized fasteners are also excellent. And 3/8" not 5/16"

That's why we don't drive in the rain if we can help it and never on treated roads. It does help living in a state where any road chemicals are kept to a minimum in winter.

I remember driving behind the salt truck every winter in Germany. It dispensed salt like it was seeding a lawn. We did have a yearly pass to the car wash where they washed the underside of the car. Before Fiat started galvanizing, they were rust buckets in less than two years.

Pierce

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #9 – September 23, 2024, 07:02:53 pm

Quote from: Pierce & Gaylie Stewart – September 23, 2024, 06:56:01 pm

That is why I did not seal the angle iron...

Sorry, but I disagree. BOTH need to be sealed. The original Rolocks on your coach (heads in angle beam) have serrated heads which WILL allow water to migrate up the threads.

No experience with the huck bolts-- don't know if they are water-proof or not.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #10 – September 23, 2024, 08:04:07 pm

Quote from: wolfe10 – September 23, 2024, 07:02:53 pm

Sorry, but I disagree. BOTH need to be sealed. The original Rolocks on your coach (heads in angle beam) have serrated heads which WILL allow water to migrate up the threads.
No experience with the huck bolts-- don't know if they are water-proof or not.

After we brought our coach home, I discovered several missing and failed Roloks. Using a chisel and single jack, I forced the big angle iron away from the rectangular tubing and then used a sawzall with diamond grit blade about 9 inches long. They can be twisted a bit for rough work and only about $15. The amount of rust trapped behind the big angle iron was amazing (as seen in old photos on the forum) With most of the rust removed, I used spray galvanize with the little red tube to coat the inside as I progressed in about one foot sections across the coach. I then used 3/8 316 stainless bolts, washers, etc. 316 is the type used on rigging, rails, general fasteners on yachts and is more corrosion resistant than 18-8 or 304 stainless. I cleaned the big angle iron and then used a black rust resistive paint. I did not seal it and have not seen any rust since then. And no, there is no electrolysis problem between stainless and mild steel.

As I've said several times in the past, Roloks are almost the worst fastener it would be possible to use on this exposed location on a motorhome. They are designed for fast construction in steel buildings that will never be exposed to water of any kind. Excellent for that application but not this one. How much would it have cost to hot dip galvanize the bottom of the coach? About the same mentality as fitting steel wheels as the inside dual instead of Alcoas.

Pierce

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #11 – October 05, 2024, 11:29:52 pm

Thought I would post some follow up photos of where this has led me too. I originally thought the water was just getting in from the underside but i was wrong. I removed the panel and insulation on the front wall inside bay 1 that is up against that metal wall and found 7 or 8 holes in it where foretravel must have burnt through when they spot welded it. My coach must have been practice for the apprentice welder when it was being built!!

As foretravel had sealed that interior wall and insulation with caulking it forced all the water into the bulkhead area and not onto the bay floor. in all my years of ownership i had not ever seen water on the bay floor it was all forced between the floor sandwich if you will.

I have removed the floor from the top side of the bay until i found good metal and then peeled down the belly pan to get to the bottom side of all the bad metal. none of it was eaten too bad. my plan is to clean up the metal use a rust converter then apply enamel paint and seal everything back up including all the burn holes that were allowing water in.

in the pictures its pretty easy to see the holes as the light from the bay shines through. when this area was sealed off with the black painted wall without ruining your hands along the seam it was hard to know there was a burn hole at the spot weld. As suggested i will be sealing that entire area.

Has anyone else found that they had burn through holes near their spot welds? I wish i would have looked at this closer years ago, i was just focused on looking at the lower bulkhead joint.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #12 – October 06, 2024, 12:02:23 am

Rust of this nature was the demise of my 2004 Tropi-Cal. As I began working on the basement structure, I also found that this same damage was happening inside the walls. On the driver's side the wall began to sag as the bottom tubes began to crumble within. You need to confirm that the steel is still sound and stop it from rusting from the inside-out. After you are done with any welding type repairs do some planned drilling and fill all cavities with a wax. All you can really do is delay the inevitable. Hopefully for a decade or sale day.

This type of corrosion is not just caused by winter road treatment. Being in coastal areas salt air and salt or acid rain can take its toll. If stored outside weather changes and related condensation will age the coach. For most motor homes it is amazing that most of the steel is hidden and is not treated or painted in any way to prevent corrosion. Having recently repaired a slide room I see that the headers above them are untreated steel with plenty of rust lines. I also was disappointed in the number of screws that mattered were simply self-tapping. Who would think a 5/16 or 3/8 bolt holding a 2 X 3 angle bracket should not be held with a welded nut or something better than the equivalent of a large sheet metal screw.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #13 – October 06, 2024, 07:22:46 am

Would this area, if not compromised, be a good place to use Fluid Film for rust prevention?

My bulkhead experience was a little different than most. On the rear, most of the bolts passed the torque test, but the centers were literally missing - no connection between chassis and bulkhead. The bulkhead itself just had surface rust, and was easily cleaned, rustproofed, painted, and recovered.

RE the hidden steel and such... I am convinced that most RVs are designed to promote impulse buys. They are pretty, look fun, and have busy paint and interiors to look exciting. That is how people end up with slides that cover access to bathrooms, showers too small to stand up, closets to shallow for clothes hangers, etc. And the bumper-to-bumper awful stuff I see videos about. We around here have the good stuff!

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #14 – October 06, 2024, 11:08:16 am

I've seen a lot worse rust than yours. Quite a few from the past had badly rust eaten tubing. Pictures can be deceiving but if the wall thickness seems good, you could start with a Harbor Freight air needle scaler (and ear muffs) to get the loose surface rust off fallowed with a abrasive disk and then paint it with rust preventive paint or use spray galvanize and then paint it. Use next size (3/8") 316 stainless or galvanized fasteners. Order off ebay to buy inexpensive boxes of all the fasteners. They usually come from Brooklyn, NY.

Pierce

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #15 – October 06, 2024, 06:09:22 pm

I agree with Pierce, from the pictures it does not seem "that bad". Also that is amazing access to that area, did you have to remove anything like a joey bed or tank?

Hit it with a grinder + flap wheel, see what you have and make sure nothing has eaten through. As suggested you may need the air needle scaler for some areas. Some of those areas even appear lite enough that it will clean up with a scotch-brite pad. Then pick your favorite rust converter (Eastwood / Ospho / POR) to kill it, followed by your favorite rust encapsulator (Eastwood or POR).

I believe that spot welded plate extends down between the angle iron and basement tube, sandwiched in between. You must address that area by getting the existing rust out / stopping new. I think its that rusting that is pushing things apart (as the rust takes up many times the volume of the host steel). Best to hear/listen to the people who really know that area on how to proceed (hint not me)

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #16 – October 06, 2024, 08:46:48 pm

Steve has it right about the big angle iron and the spot metal sheet and cleaning the rust. My old posts back in 2008 or a little later show the amount of rust behind the angle iron. It looked perfect from the top and from behind but lots of rust was hidden behind it. The is where most Roloks fail. Rust jacking pops the Roloks right where they go into the square/rectangular tubing. This is why the torque test can check to see if any has failed. To remove a Rolok, I've found that trying to tighten them a tiny, tiny bit and then removing them makes it easier than just a CCW turning.

So, with the cover removed like you have, you can remove the Roloks for two feet or so and then force the angle iron and the tubing apart with a flat chisel and a single jack (hammer used in mining). Once you have a gap, use the Sawzall like I earlier described. Then use your favorite paint or rattle can spray galvanize plus paint to get the area ready for new fasteners. This would be after you have preped and painted the tube area. As I said, 3/8" 316 stainless or hot dipped galvanize fasteners can then be used for the angle iron, sheet metal plate area you worked on. After installing the first few fasteners, you can leave the last couple out and force a new area apart to make a gap for the Sawzall diamond blade. Just make sure the coach is very secure so you don't get hurt or worse. I used nylocks on the opposite end from the bolt head (plus flat washer).

Pierce

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #17 – October 06, 2024, 11:07:14 pm

Thanks Steve and Pierce. I have Huck bolts vs the Roloks and i can't see a way to remove them on my coach. Pic 1 is the back side of the bulk head with no bolt head too loosen and pic 2 is the front side where you see the threaded ends of the Huck bolts but no bolts on other side. i can't image the bolt head is inside the steel tube? I do think its best to get some slight separation to clean between those three pieces the angle iron, sheet steel and then the tubular steel but can't figure out how to get them apart.

Has anyone taken apart a bulkhead with the Huck bolts vs Roloks? also look at the added L braces 4 of them on each bulk heal i assume to hold the bulkhead together if something failed you would not get full separation? I haven't figured out how to get those off? Pic 3. There are 4 of those spaced across the bulkhead.

Thanks everyone for their input and help. it is incredible useful to me.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #18 – October 07, 2024, 01:03:37 am

Is it possible to use one of these methods to remove the huck bolt?: https://www.youtube.com/results?search_query=huck+bolt+removal

Pierce

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #19 – October 07, 2024, 08:51:59 am

I don't see the head of the huck bolt.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #20 – October 07, 2024, 09:04:04 am

Oxy-Acetylene torch. Get the nut red hot and then quickly hit with the impact wrench. I work on old Volkswagens. I know all about natures Lock-Tite.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #21 – October 07, 2024, 10:00:54 am

Torch or grind off what you can see down flush with the angle iron. Then use a punch or something to drive what remains in past the big angle iron and sheet metal. Same with the bolts on the bottom of those small angle irons. This is assuming that the original construction is similar to the older units. Maybe by 2007 they were different enough that my idea wouldn't work.

Quote from: turbojack – October 07, 2024, 08:51:59 am

I don't see the head of the huck bolt.

A very good point. Where do they go???

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #22 – October 07, 2024, 10:22:13 am

Quote from: turbojack – October 07, 2024, 08:51:59 am

I don't see the head of the huck bolt.

Quote from: Dave Larsen – October 07, 2024, 10:00:54 am

A very good point. Where do they go???

They do make a blind hole version, basically an industrial pop-rivet. I wonder if BOM is what they used?

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #23 – October 07, 2024, 01:21:20 pm

That was my biggest wonder, where is the head of the Huck Bolt. And i think watching some of the videos and more looking on the internet it is more of a rivet head that would be inside the steel tube rather then a bolt head on the other end of the steel tube. I might just drill a small hole in that square tube and insert an inspection camera to see but i bet is will be a rivet style head.

Re: Just Noticed Some Front Bulkhead Rust. Thoughts...

Reply #24 – October 08, 2024, 06:33:40 pm

Quote from: Bob Hawkins – October 06, 2024, 11:07:14 pm

also look at the added L braces 4 of them on each bulk heal i assume to hold the bulkhead together if something failed you would not get full separation?

I was thinking about this and my guess would be they are just assembly aids for when the sub-floor is joined to the front and rear bulkhead. They look like cradles to help temporally support the floor in position while its is clamped and joined to the bulkheads.

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