Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Topic: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III) (Read 376 times) previous topic - next topic

Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

October 07, 2014, 11:40:23 am

Just for a "something to do" idea.
I have been going over the sewer compartment and found a few details that needed addressing- the main one I would imagine affects a lot of us. The cut out of 1 1/4" tubing for drop down sewer pipe cover was filled with a rubber mastic/caulking by FT so I dug this lump out and low and behold the first few inches had rust on them (internal). They had stuffed some paper or? so it would be possible to fill tube with this rubber compound. I pulled it all out then chipped away at rust and vaccumed it out before spraying Ospho ( Por 15) right into the tubing. Left it overnight then sprayed undercoat rubber into it and again left overnight to dry. I made a sq block to fit out of Mahogany then tapped it in and caulked with an underwater type roof silicone. After levelling it off flush with end of tube and once hard I painted it with the same rubber spray. Hopefully that is it for ever, but a simple task that most probably everyone misses looking at (possibly save Don)
JohnH

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #1 – October 07, 2014, 12:00:21 pm

John, sounds like a fore ever fix to me. Did you take a few photos???
Dick

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #2 – October 07, 2014, 06:09:23 pm

No I did not Dick as the job was one of many things I was doing at the same time ( rebuilding the outboard motor trim cyilinders for a neighbour) etc etc etc and totally forgot about doing that untill too late. It is simple to "dig out" the caulking and you will see what I mean I am sure. Right behind that is the paper plugging so pull that out. I am fairly certain you will find rust and if not no big deal just plug up again and re caulk. I would still spray some Por 15 inside tubing though.
JohnH

picture after sealing and painting with rubber underseal.

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #3 – October 07, 2014, 10:07:08 pm

Quote from: John Haygarth – October 07, 2014, 11:40:23 am

I have been going over the sewer compartment and found a few details that needed addressing- the main one I would imagine affects a lot of us. The cut out of 1 1/4" tubing for drop down sewer pipe cover was filled with a rubber mastic/caulking by FT so I dug this lump out and low and behold the first few inches had rust on them (internal).

John,

Your repair project is something I need to get to, but mine is further damaged than yours. From your description, your box tubes are still intact. Your treatment has probably prevented the deterioration that I now find with mine.

Assuming that the cutout area is framed with the box tubing, both of my sides have already suffered significant deterioration. One of the reasons for that appears to be the edge gasket application. On both sides of the sewer door, the gasket stops short of the opening. On the door itself, the edge gasket is totally missing. The first picture shows the door closed, but the integrity of the door material itself has already deteriorated to the point that the closed door does not even come up to the adjacent edges.

The second and third pictures show the edges of the two sides. Both of them show substantial failure of the box beams themselves due (probably) to rust. I have an idea how Don would, and did, fix such a problem. I am not near that talented.

Can anyone suggest a lower tech way of repairing the damage without removing and replacing those box tube segments? I suspect that, with as much moisture has lived in that area, that the rear box tube may be headed for the same fate. What have the rest of y'all done to repair this (apparently) very common problem area?

Thanks,

Trent

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #4 – October 08, 2014, 12:09:49 am

Actually Trent you may be still ok. This is showing surface rust only and I am sure you are still good inside the tubing. This looks like just the glue that was used to hold the black rubber cover on. I would suggest you cut away this area you photographed and scrape it clean. Remove the filler in the tube and pull out the paper filler. get an old 1" chisel and dig away any rust as far in as possible. By the way they did use a thin angle strip to cover this cutout so take it off if possible to get to base of bay. Spray rust preventative in (ospho or Por 15) and let it dry, then finish up as described before.
JohnH
Extra comment-- your problem started because you do not have any rubber seal strip on the drop down door as shown in your pictures. Put something there right away even if it is only the foam door weather strip, as long as it makes contact with the door. This allowed water in from road.

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #5 – October 08, 2014, 01:30:16 am

Quote from: John Haygarth – October 08, 2014, 12:09:49 am

By the way they did use a thin angle strip to cover this cutout so take it off if possible to get to base of bay.

John,

Thank you for the quick and detailed response (and encouragement).

I had thought I was looking at the edge of rusted through tubing. If I am understanding you properly, I feel much better.

Thanks,

Trent

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #6 – October 08, 2014, 01:53:21 am

Trent,
I couldn't say from the pictures that the box beams (or as I call them, square tubing... Box Beams being the functionality and square tubing being the material) have failed. The thin sheet metal which wraps the end of the utility notch needs to be removed and the caulking "plug" and old glue cleaned up to reveal the actual condition. Additionally, I would remove the short section of trim that goes from the notch back, because that short piece should be relatively easy to take off. Be prepared for a few screws to break.. I would try to get some penetrating oil liquid wrench type stuff down in the inside of the square tube after you remove the "plug". It is quite possible that the only real damage is non-structural and just on the exposed edges of the square tube that terminates at the notch. If so, just clean it up and reseal it. In any case, I would bet my farm that the outer square tubing is welded to all the transverse beams and would be no easy do it yourself project. But in my opinion, the flashing and the black ribbed rubber matting doesn't really help anything. It just hides the sins and gives the water a place to hang out. If anything, some kind of Rhino Lining type coating would be a much better choice, or even some rubberized rattle can undercoating. Or even just clean and coat the metal that forms the notch so you can keep an eye on it. Just my two cents...

To recap what I said in a different thread, the basement outside edge framing changed on the 2000' model year when they changed to the black batten trim. I haven't examined one, but it appears to me that they moved the outer longitudinal frame members out about an inch and a half (or added another course of 1.5" square tubing in place of the 1.5"X1.5"X⅛" thick angle iron that used to form the outer rail of the basement frame. I suspect that they just eliminated the angle iron and just added another run of the square tubing out to the edge and just specified the extrusion with a "c" channel profile that overlapped the edges of the fiberglass sheet material (Filon or FRP). My experience with the older style trim leads me to believe that I know why they made the change. Anyway, if those square tubes on the outside edge of the basement floor are not sistered with other longitudinal tubing, the basement floor would be significantly weaker than in prior years, unless they used much thicker walled tubing on the outside course. Bottom line is, that it is probably not as bad as you are currently thinking... but if you are like me, you just have to find out

Here is a picture of the notch area in the early stages of my repair, after the worst tubing has been cut out, and new material (11 gage) welded in its place. I possibly could have stopped after this stage and buttoned her up. But I didn't...
Don

Quote from: TulsaTrent – October 07, 2014, 10:07:08 pm

John,

Your repair project is something I need to get to, but mine is further damaged than yours. From your description, your box tubes are still intact. Your treatment has probably prevented the deterioration that I now find with mine.

Assuming that the cutout area is framed with the box tubing, both of my sides have already suffered significant deterioration. One of the reasons for that appears to be the edge gasket application. On both sides of the sewer door, the gasket stops short of the opening. On the door itself, the edge gasket is totally missing. The first picture shows the door closed, but the integrity of the door material itself has already deteriorated to the point that the closed door does not even come up to the adjacent edges.

The second and third pictures show the edges of the two sides. Both of them show substantial failure of the box beams themselves due (probably) to rust. I have an idea how Don would, and did, fix such a problem. I am not near that talented.

Can anyone suggest a lower tech way of repairing the damage without removing and replacing those box tube segments? I suspect that, with as much moisture has lived in that area, that the rear box tube may be headed for the same fate. What have the rest of y'all done to repair this (apparently) very common problem area?

Thanks,

Trent

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #7 – October 08, 2014, 11:42:57 am

Just an add on to my last posting. Another way for any road water etc to enter this bay area is from the hole on the right for sewer door and pipe for storing flex tubing. A while back I found that the 4" black pipe and elbow was never fixed properly to the back of this door and was allowing water to get thrown inot the opening by Duals. I took elbow/pipe off and cleaned it all up then glued it back and put a couple of screws thru the joint to hold it more. I then sprayed rubber underseal all around and since then no more water intrusion from that area. I still do have to put a "cap" on the end of this pipe so dirt etc does not get "fired" down the tube from opposite side tyres and when I do that in a few days I will drill a few drain holes in the bottom of 4" pipe to allow any that somehow finds itself there to drain out.
I do agree with Don that the rubber piece on bay floor should come out if there is any thought of water under it but mine was good so all I did was make sure the corners had a good seal and all edges too then I sprayed (here I go again- but I love this stuff) the rubber underseal on this ribbed product then allow a few days to dry. I think I could pour water in there now and be safe!!
JohnH

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Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

October 07, 2014, 11:40:23 am

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #1 – October 07, 2014, 12:00:21 pm

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #2 – October 07, 2014, 06:09:23 pm

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #3 – October 07, 2014, 10:07:08 pm

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #4 – October 08, 2014, 12:09:49 am

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #5 – October 08, 2014, 01:30:16 am

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #6 – October 08, 2014, 01:53:21 am

Re: Sewer drop-down door cutout restoration (split from Re: What did you do to your coach today III)

Reply #7 – October 08, 2014, 11:42:57 am

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