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pinkflamingoes 05-05-2013 11:38 PM

What goes under the new floor?
We are getting ready to put on the new floor/c-channel/belly pan/shell back on the frame. before we put on the belly pan or floor, is there any crucial wiring or plumbing or gas or what have you, that needs to go inside belly pan? Would be nice to pull that before we put on the pan. I figure brake lights etc., any other?

ROBERT CROSS 05-06-2013 05:16 AM

Don't know if anyone's tried this but it looks like it might be a good option.
I'm sure someone with more experience will chime in.

Good luck in your refurb.


pinkflamingoes 05-06-2013 12:55 PM

Hi Robert, thanks for that. I saw a trailer with interlocking foam tiles, they were very firm and I dont think they were glued down. It would be nice to have that, if something gets broken or there are floor problems, we could get to it a lot more easily.

My question was mostly about wiring and plumbing; but we figured out that we have to determine our layout before that. After that, providing things are close to sort of right, we wire/plumb etc. I think we are going to leave a section of the belly pan temporarily open (not sure how) to access that area if we need to. I also fabricated some jacks-- well they are mostly to pull the trailer up on to them so it is we will probably be able to get stuff in there if the belly pan is almost on.

I wonder how flexible that stuff is that you posted? If its stiff like wood it might not be a good idea. Anyway...thanks...we answered our own question.

Silverflames 05-06-2013 01:16 PM

I believe most of the wiring goes into the walls between the two skins. My 30 amp breaker panel is on the inside wall. Wires run up from there in the wall. A few leads might go other parts of the trailer if you add them.

Plumbing goes inside the trailer to keep it from freezing. Holding tanks can be under the trailer or inside depending on your set up.

pinkflamingoes 05-06-2013 10:13 PM

Ah, tanks. How could I forget. We even ordered them and own them but during the "hiatus" we lost our focus. Thank you!

BIGED52 05-07-2013 12:32 AM

Propane lines!!!
Ingrid, Don't put the propane inside the frame at all ... the line runs on the bottom of the bellypan and only T's off to go to each appliance location. On my trailer all the supply lines had exterior shut-offs before they were run up (thru the belly) to each appliance. Remember that if the lines were inside the belly and a leak occurred it would allow gas to built up in that space and could cause a major explosion. (Not Good)! All your wiring except the leads to the electric brakes should be inside the walls (above the floor) with junction or switch/outlet boxes wherever a connection is made (not just twisted wire & tape or wirenuts like from the factory in '67! I too am re-thinking best insulation for under the sub-floor. Let me know what you decide on doing with that issue. I still have skin splits at damaged wheel wells to deal with as well as needing new wheel wells fabricated. I was impressed by the ones you two did. Mine of course are only for single axle so a little less involved. Glad to hear you enjoyed the classes that you attended. I may try to go out next year if work allows. It just wasn't happening for this year. So great to hear that you are back on the re-assembly of you trailer. Hope you get it at least together enough to use as a Aluminum Tent this season. Happy Trails, Ed

pinkflamingoes 05-07-2013 05:10 PM

So...propane lines *under the belly pan, visible withe belly pan on? Or over the floor, inside the rig? I have a manual, maybe I should read it!!

As for insulation, a lot of people were talking about the batting type of insulation (big rolls of pink fluffy stuff that is wrapped in paper, looks like cotton candy...) but we are going with this thin stuff called "Prodex". You layer it three times with the tape they include. I'll send you the link after this. We are going to put it in between the inner/outer skin too.

We don't want squishy foamy insulation because of mice. Hantavirus is just my LEAST favorite fatal disease!

Wheel wells; Jeff had fabricated them incorrectly so he had to add a few pieces. Used steel rivets not aluminum.

We used the old ones as a template and we still blew it...but we finally created a facsimile thereof. If you have electric sheet metal shears the are great.

once riveted together I sealed every seam and rivet hole (not Vulkem) and then then coated all of them with POR15. The only reason I did the outside of the wheel well was because the can of POR15 had enough left and trying to seal that stuff for future use is a pain, so I just used it up.

The paint job covered up most of my horrifying but effective caulking job. I smeared that stuff on like peanut butter with my finger in bigger seams. No one's going to see it anyhow!

It's nice to be back in the game!

pinkflamingoes 05-07-2013 05:16 PM

Prodex at

I don't remember which's been a few years since we ordered it and its still in a roll in our yard.

ROBERT CROSS 05-07-2013 06:33 PM

LPG lines outside!!

Think leaks inside the coach...not good.
Easy to inspect.;)


HiHoAgRV 05-07-2013 07:35 PM

The only thing I ran inside the belly pan was brake wires. If I had wanted one, I would have run 110 volt, 10 gauge wire (inside of some PVC) from the tongue back to the area for the breaker box for a genset hookup.

pinkflamingoes 05-07-2013 08:26 PM

Roger on the LPG lines outside. And I need things explained many times...thank you. Gas-anything scares me.

Silver Hawk 05-07-2013 09:57 PM

Question - why put on the belly pan until your done with the interior? Seems like having access to the underside would be advantageous while working above for those things you did think of - and does it doesn't matter when you do it?

pinkflamingoes 05-08-2013 12:12 AM

Putting the shell back on goes in this order: floor, C channel, shell/belly pan. So that means you can't work on the interior until after floor is down.

That's why we would like to know what we can more easily install with the shell and belly pan off, but it looks like we are just going to jump in (after pulling brake wiring underneath, etc) and if we end up having to pull off some belly pan to install something down there, so be it! I just hate having to go back and undo something because we didn't plan ahead. I worry too much.

pinkflamingoes 05-08-2013 12:16 AM

Oh maybe you didn't see below that our whole shell is off the frame and we are going to put in a new belly pan too. I SO wish that we could have just put in a new floor and gotten on with it; but it was all in bad shape so we ended up taking off the shell.

Silverflames 05-08-2013 07:51 AM

Any thoughts of installing bot down/up access panels on your belly pan? I'm planning on putting some by the holding tanks do I can drop small sections to get to the plumbing for repairs. If I ever get to that point..

Minno 05-08-2013 08:06 AM

Might be easier to drop your tanks in place before you put in the floor. Speaking from experience, it's "fun" to lay on the ground and shove the fresh water tank into place with your feet...... :lol:.
Propane lines definitely need to go on the OUTSIDE of the belly pan. We put Pex over the lines to protect them from road debris hits when we installed them.
We ran our battery lines in the belly pan because we moved the location of the converter and battery, which are not near each other. It was easier to go underneath the floor than try to snake things through the trailer. Otherwise all our electrical is in the walls.
Water lines should be inside the trailer to protect from freezing. (Just reiterating what has been said.)
Good luck!


pinkflamingoes 05-12-2013 02:14 PM

Hmmm. Pex over it. That's a good idea.

CaddyGrn 05-12-2013 04:23 PM


When Don did our Bambi and put on the belly pan.... he made access doors to the critical areas in case he needed to do repairs.... he made a separate access for the holding tank and pipes, etc. That way in case of problems the whole belly pan doesn't come off or have to been replaced.

Just a thought to throw out there.

pinkflamingoes 05-12-2013 08:13 PM

It's called being proactive and it's a great idea. Give Big D a kiss from us!!

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