More belly pan questions

[ALANSD]

I need to cut the back end of the belly pan off my 66 Overlander, to remove the galvanized tank pan. It's bolted on and I need access to cut the rusted bolts.
Is it ok to cut the pan across the width of the trailer and then how do I reattach it ?
Looking for some tips.

I have read so many belly pan posts I am going blind!! For real.
I guess I will try to reuse the aluminum that is there now.

[RM66caravel]

Where is the seam or did they run the length of the trailer? If they did go to the point that you have a rivet line from side to side and remove those rivets and cut just (about an inch) behind that line towards the back of the trailer. This will give you a plumbing or tank access. You may need a 6inch wide by 7 and a half foot long piece of aluminum to overlap your new cut after your done. Order the large flange rivets from VTS for the repair. remember never cut if you do not need to and make it easy on yourself.
Cliff

[kevinb]

Mine attached at the rear bumper, I drilled out the rivets there, then cut the aluminum on both sides going toward the front, and left the front uncut. Then I rolled it back toward the front to expose the galvanized pan. Then to re-attach I used 10" wide scrap to overlap the seam where I cut it, riveting the patch on both sides of the seam.

Don't know if I explained it so you can understand it, pm me if you want.

[ALANSD]

Thanks. i peeled back the belly pan under the black tank, but. Need more access. looks like one big sheet under there.

[ALANSD]

The patch makes sense.,thanks

What did you use to do the cutting?

[kevinb]

sheet metal shears

[kevinb]

my belly pan had a seam right down the middle, once both sides are cut forward that should give you plenty of room, if it was like mine.

[Frank's Trailer Works]

get some shears and wack off what you need. It's just some aluminum and they smelt that stuff every single day...

The part you are going to struggle with is the bolts. The heads are above the floor and you will not be able to remove them with out taking the bathroom module out. SO... how to do this? First blast the nuts(after you peel back the belly pan) with BP Blaster two three times a day for a few days. The trick is to spin the nut off without spinning the bolt. The bolt is an elevator bolt with a fairly small head. I would suggest you buy or borrow an impact gun to remove the nut. When you squeeze the trigger do it with full confidence that the nut is going to spin right off. Cutting them will be a disaster when installing the new pan. You will not be able to put new bolts in without removing the bathroom.
I just put a new pan in a 64and it was easier since the entire trailer is empty.
Just be forewarned, you might not like what you see in the rear 3" when the pan is down. Sometimes ignorance is bliss.

Feel free to call me if you want, Allan.

[ALANSD]

thanks Frank. I have an impact wrench and will try the PB Blaster once I can see the remaining bolts. Will it be ok to simply screw in the new box to the floor?
The pan is down now just not quite enough. The rear frame and the above plywood look fine. Just some rust on the support angle iron. I can clean that up and POR it.

[Frank's Trailer Works]

I think you could screw it in but there will be only 5/8" of plywood to screw to. I would worry about a full load in the tank pulling the screws out.

[kevinb]

I did have access to mine so I used bolts... I wonder if heavy duty threaded clips would work?

[ALANSD]

I guess I will go with short fat wood screws. Lots of them
Oh yeah TANKS TO ALL OF YOU- the box is now out!!
I had to break the last few bolts off with vise grips. They broke off right at the wood.

[ALANSD]

Now off to get a box fabbed up. I am guessing about 100 bucks.

[Frank's Trailer Works]

$100... maybe if out of galvanized. I would say $300 out of stainless...

[ALANSD]

I am thinking galvanized and flex sealed.

[ALANSD]

Got the new box today. Looks great and is nice and solid.$125 was the damage.
Would it make sense to drill a few weep holes in the bottom? Small ones to let out any possible mositure?
I intend to flex seal the inside but just wondering.
It will be great to get the belly pan back on and all tightened up.

[ALANSD]

Box is on. Bumper trunk is back on, the riveting killed my hands!
Belly pan in mostly on, needs more rivets and I am out for the present.
It was hard to line up rivet holes, and I had to drill some more. Just not enjoying laying on my back with my head held up to do all this.
Sore hands and neck for sure.
Getting there. Will need to run a patch over part of the seam in the pan, its got a few defects there..

[robwok]

Just wanted to jump in here. Make sure you fill your old black tank with water. Mine looked great, and the original pan was almost complete, but when I filled it with water, it leaked like a sieve. It was broken at the Thetford flange. I could have gotten the original glass on flange from VTS, but then would have to use the Thetford valve. Also, would need a new pan, and then I still wouldn't have any good way to add a gray tank. $175 is the cheapest I can get a galvanized pan made for around here (called 4 shops) Then fiberglass, Thetford setup was about $75, and then I'm left with a pretty small black tank that is about 50 years old, with 50 year old technology. Plus, since I got a new toilet, I have to cut out the old female thread ABS, and move it back an inch and re-glass a new one on.

Here's the better option that I came up with:

Sheet of 4x8 ABS was $100.00. I got 2. That's enough for 2 grey tanks as well as my new black tank. I can slope the bottom of the black just a wee bit to help it drain to the new Valterra in back. The gray line gets cut where it used to go into the valve just after the Black valve, and instead routs across the back of the trailer just inside the access panel. Now, it drops to the street side of the black, and runs up to the front of the trailer where it enters the gray tank. That one empties into the one behind it, then that follows back to the back, where it goes under the gray "supply" line wraps the back of the black, and joins the Valterra mixing valve, and ends at the same spot in the back as the original hookup. I strugged for a year to figure out how I wanted to add this in without pulling my tub out.

Since my floor covering is up, I'm driling new elevator bolt locations. (snapped off the old rusted ones, poked them, and pulled them out from the top) Dropping new bolts down for the support straps, and then drilling some wood screws in to the flange I'm putting on the black tank.

The new black tank still has to have that odd cutout for rear, floor mounted tanks, so I couldn't use any tanks off the shelf. Going to put in a tank heater, but I may just run my original furnace duct line back there with a gap in the insulation to allow it to surround the tank like the original.

[robwok]

Whoops. Missed the post where you had it back on.. Well, best of luck! I know Frank was posting on this thread, so this may be something he'd want to consider in the future.

Not sure how a powerpoint drawing will save, but this is my plan for updating my trailer. Something to consider if you want to add gray tanks in the future. I think your option at this time, if you kept your setup, would be to run that gray line across the back of the trailer, then up a little bit, then drop it down through the floor, forward of the black tank. You'll just need to hook up twice to dump as you'd have to have 2 locations for dumping. Though, your trailer config may be different than mine.

[ALANSD]

THANKS ANYWAY...My black tank was not leaking. It had water and Clagon in it to cleanse it. It had a small leak at a place where the valve is located, I sealed that and it was ok.
Last few rivets to put in the belly pan and then a 10" long patch on one side and I am done...with this part of the project anyway.