Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: corndog254 on September 23, 2014, 12:15:28 pm

Title: Rust
Post by: corndog254 on September 23, 2014, 12:15:28 pm
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?
Title: Re: Rust
Post by: Kemahjohn on September 23, 2014, 12:46:50 pm
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.
Title: Re: Rust
Post by: D.J. Osborn on September 23, 2014, 12:57:41 pm
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.
Title: Re: Rust
Post by: corndog254 on September 23, 2014, 03:01:08 pm
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.
Title: Re: Rust
Post by: krush on September 23, 2014, 04:19:28 pm
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.
Title: Re: Rust
Post by: Kemahjohn on September 23, 2014, 04:37:05 pm
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.
Title: Re: Rust
Post by: jor on September 23, 2014, 06:34:55 pm
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

Title: Re: Rust
Post by: Don & Tys on September 23, 2014, 07:02:16 pm
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.
Title: Re: Rust
Post by: Pierce & Gaylie Stewart on September 23, 2014, 07:50:43 pm
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 (http://www.mechanicsupport.com/aircraft_tube.html)

Pierce
Title: Re: Rust
Post by: jor on September 23, 2014, 09:45:04 pm
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
Title: Re: Rust
Post by: pocketchange on September 23, 2014, 11:58:41 pm
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
Title: Re: Rust
Post by: John Haygarth on September 24, 2014, 12:18:06 am
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
Title: Re: Rust
Post by: wolfe10 on September 24, 2014, 09:28:03 am
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.
Title: Re: Rust
Post by: John Haygarth on September 24, 2014, 11:45:06 am
 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
Title: Re: Rust
Post by: wolfe10 on September 24, 2014, 11:49:56 am
John,

Yes, a similar "cover" can be crafted for the vertical "inlet" side vent without materially reducing air flow.
Title: Re: Rust
Post by: Don & Tys on September 24, 2014, 12:46:28 pm
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 ;)
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