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Topic: Rust (Read 818 times) previous topic - next topic

Rust

I'm getting my fuel lines replaced.  When they removed trim pieces around the fuel compartment door some areas of rust became obvious.  The angle iron that the basement door seal attaches to that runs the length of the coach above the basement doors is rusty in many areas.  The angle iron that runs along the bottom of the basement doors is much worse, with a lot of scaling already happening.
Anybody else see this problem?  What did you do about it?
BJ Holden
'98 U320 36'
Motorcade #16754

Re: Rust

Reply #1 –
First, find the water leak!  If the iron is still structurally sound, I would wire brush to clean and then treat with Ospho, then paint.  Be very careful not to expose aluminum to the Ospho.  The Ospho will stop the rust process, but you must find where the water is coming from and fix that or damage will continue.
Current coach 1996 U320 40'
Previous coach, 1990 36' U280

Re: Rust

Reply #2 –
I agree. You definitely need to find that water leak and fix it. I also strongly suggest you carefully check to see where else there is rust damage. It is certainly possible that there are major structural issues, and if so then you need to find them ASAP.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: Rust

Reply #3 –
Good question.  Where is the water coming from?  I think on the bottom rail it is likely water that gets in from wet road spray.  On the top I don't know.  Knowledgeable people here in Nac think it is just slow rusting over time due to the fact the metal framing inside was not painted to begin with.  Apparently it is common to take off the skin of a coach and find the steel inside to be coated with rust.  If so a lot of us should have this problem.  I looked where I could at some of the other coaches around here and see some similar signs on the upper rail.  Can't tell on the bottom without taking the cover piece off.
BJ Holden
'98 U320 36'
Motorcade #16754

Re: Rust

Reply #4 –
Just imagine if they fabricated the entire structure, and then dipped it in a coating............of course, they couldn't do that, because then the FT would last forever.
1998 U270 34'

Re: Rust

Reply #5 –
Usually the water is coming from fresh water somewhere in the coach.  The wet bay is the first suspect.  The water gets to the square tube frame and then runs the frame.  The leak could be far from the evidence of rust that was found.  You definitely need to investigate more.  The good news is--- Foretravel is very good at repairing / replacing bottom bay framing and making it like new again.  Talk to Wayne in the chassis shop.  Not as expensive as you might think.
Current coach 1996 U320 40'
Previous coach, 1990 36' U280

Re: Rust

Reply #6 –
Our 320 also had rust on that rail (fuel tank compartment, both sides). I cleaned it off and painted it before reassembly. The cause was obvious; road water was entering through the open trim. The steel had no protective coating and rusted easily. I recall posting at the time asking others if their trim was also open but I don't think I got any definitive replies. I've checked several; some are caulked and others are not. For instance, our current U-300 is caulked. I'd clean it up, prep it, paint it and put a nice shiny trim piece back on. Then caulk it closed. On ours there was definitely no fresh water leak. The arrow points to the area where the road water would enter.
jor

93 225
95 300
97 270
99 320

Re: Rust

Reply #7 –
I would say that the rust should be cleaned off and then treated an coated. The metal may well be sound as the material is ⅛" thick by 1.5"X1.5" angle iron, but the only way to know for sure is to clean it up first, IMHO. As far as sealing the ends of the trim, I am of a mind that says water needs to have a way out because I think water intrusion into that area would be difficult to stop altogether. Also, if it is plugged on both ends, you won't be able to tell. I went back and forth on this issue when I was replacing my bottom trim with the newer style that started with the year 2000 models. This required a few extra steps to fit to the older style sills, but the point is, I decided to leave the area open on the ends and even drilled weep holes in the bottom. Notice that all the heavy rectangular steel framing that supports the engine and supension is open on the ends. As long as the steel can dry out thoroughly in between exposure to water, the iron oxide coating that forms is actually protective. That said, I am no fan of rust which would become obvious to anyone who wades through my posts on my bulkhead repair ::).
However, if I was going to plug the ends, I would inject polyurethane foam (like used in sealing pipe penetrations in walls etc. in plumbing) through holes drilled every 8" to 12" to completely fill the void and then use plastic plugs to block the holes. That way, if done well, there would be no void for water to accumulate in and no chance for condensation to form in the void. All of the above is just my opinion and would likely not be sanctioned by the Mothership if you were to ask them. There is a lot more that I could say about the subject, but that will have to do for now.
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Rust

Reply #8 –
The very best rust preventer is aircraft tube oil aka boiled linseed oil. Synthetics have been developed but don't work nearly as well and have cost Fokker Aircraft and their operators hundreds of thousands of dollars. Just inject some (depending on how long the tube is) in each tube and it will climb the walls and ceiling of the tubing until everything is coated. All tube framed aircraft have used it since planes were flying. Professor Hill and his buddies are the only ones trying to sell the synthetic stuff.

Don't throw any linseed oil rags in the garbage can. That's how the fire that nearly got us was started.

See article at: aircraft tube oil

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Rust

Reply #9 –
Quote
As far as sealing the ends of the trim, I am of a mind that says water needs to have a way out because I think water intrusion into that area would be difficult to stop altogether.
Don makes a good point here. On ours, I was just about certain the trim had never been removed and there was no evidence that there had ever been caulk on the end. Made me wonder if Foretravel had designed it that way.
jor
93 225
95 300
97 270
99 320

Re: Rust

Reply #10 –
I'm an OSPHO fan. 
Remove the scale (wirebrush,) wipe it (dust/loose stuff) off with something (spirits) if it has grease is present.  Then brush on the OSPHRO.  Let it dry (overnight).  Wipe off any white residue.
Paint (brush) with oil base primer and any name brand (automotive) oil base spray paint.
ie: Rustoleum.. pc
S/W Houston 95" U320C SE/40' 
Build #4778  Cummins M11
Repairs & Covered RV Parking (BAO)
PPL is close..

Re: Rust

Reply #11 –
In the front bays I found when I took off fuel tank fibreglass cover that a vent which is just behind the left hinge arm for door allows all the road material into that bay. I have closed that off and put a kind off deflector there so none enters this area. It is a longish slit with a badly shaped baffle in front (wheel well) that does not stop intrusion. Check this carefully as I feel it is important.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Rust

Reply #12 –
To expand on John's suggestion:

Yes, if there is propane in the same bay, there must be a vent through the floor (by law and for real safety reasons).

Like John, I did not like all the water and dirt splashing up into that bay-- or worse, finding its way into the beam area around the opening.

What I did was cut a piece of fiberglass four inches wider and longer than the vent opening. Then, using some 3/4" aluminum box beam (Home Depo) used the box beam to space the fiberglass down.  Screwed the fiberglass and box beam to the underside of the vent area (used 4 "widths" of box beam to support the fiberglass).

Now the vent is still functional, but water and dirt intrusion is down 95%.  Took 30 minutes and $9 to do.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Rust

Reply #13 –
 Brett, the opening I was referring too is high up the left side wall (on ours) right behind the curved arm of Bus style door "hinge". It allows air into the upper area but on the outside "above Bulkhead angle" this deflector for want of a better name does not deflect the road junk thrown up by wheel. That is what I changed to totally stop any moisture entering, only allowing air.
I did put a temp' system like you mention under the hole in base but need to do a proper one similar to yours.
Now I have a clear pit I can get to a few things ^.^d ^.^d
First I have to go over the tow car I just bought and install all the wiring and parts etc.
JohnH
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Rust

Reply #14 –
John,

Yes, a similar "cover" can be crafted for the vertical "inlet" side vent without materially reducing air flow.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020
 

Re: Rust

Reply #15 –
Here is a picture of what the factory puts up high on both front and rear bulkheads: One on the rear that is where the fresh water overflow comes through, and three in front (at least on the ones I have seen), two with ABS pipes to bring air into the battery compartment, and one on the curb side in the Fuel Tank/Propane compartment.
Edit: As you can see in my picture, the air spring and shock are removed. With the air spring and shock in place, it is very difficult do much with the vent cover that is directly behind the air spring.
Don
P.S. John, next time I come, I promise to share your pit with you ;)
Quote from: John Haygarth –
Brett, the opening I was referring too is high up the left side wall (on ours) right behind the curved arm of Bus style door "hinge". It allows air into the upper area but on the outside "above Bulkhead angle" this deflector for want of a better name does not deflect the road junk thrown up by wheel. That is what I changed to totally stop any moisture entering, only allowing air.
I did put a temp' system like you mention under the hole in base but need to do a proper one similar to yours.
Now I have a clear pit I can get to a few things ^.^d ^.^d
First I have to go over the tow car I just bought and install all the wiring and parts etc.
JohnH
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson