Seam sealing and patching leaks

[Paladin]

I'm getting some leaking along the sides where the new fiberglass panels were riveted on over where the windows used to be and also up in the ceiling at the rear presumably around some rivets or maybe around the hatch? (the interior tiles are still in place so I can't readily see) The hatch it's self is not leaking.

My question is what has everyone used to seal in there around the new seams? Some rubberized sealer like a roof sealer? Some calking compound?

I don't want to have to deal with leaks after the exterior walls are up so I need something that I can trust.  I thought of shooting some of that "Good Stuff" foam in behind there but I've found that it degrades over time, besides, that's not a sealer anyway. I've coated the inside metal with POR-15 and now I need something to stop the leaks!

[Tenor]

Is it cold right now in Utah?  Could you be getting condensation instead of leaks?  I had no idea how much they sweat without insulation and moisture barriers.  It can almost be like rain!

[Paladin]

Is 10 degrees cold? 

I actually noticed the leaks when it was raining last fall.

[tekebird]

3m 5200

[boogiethecat]

I use Sikaflex 1A that's made for the construction industry. It's amazing, cheap, works really well for sealing small or large cracks, voids or outright holes.  I also use to to seal laps between sheets, and just about every sealing job outside or in my bus.  It's paintable.  It's only down is that it's really easy to make a mess with the stuff and it's not as easy to clean up as some things are.  Naptha on a rag, though a fire hazard, works really well for the cleanup job.

The stuff available from construction supply houses. Black seems to be the most common here in town but it also comes in white.
Get it from Sunshinesupply if you can't find any locally... last time I got some it was only $2-3 per caulking tube.
http://www.sunshinesupply.com/

[rcbishop]

Sikaflex.....SikaUSA on the web....great stuff.

FWIW
RCB

[tekebird]

follow up on the 5200.......heavily used in the marine industry.  used to mate deck sections to Hulls on Fiberglass boats.

When looking for conversion stuff....always look to the marine industry, it has been around forever and marine stuff is built to withstand a far more harsh environment than a Conversion

[Hartley]

Rubberized undercoating in a spray can.

Covers up cracks and places where condensation can form in tight places.
that was one of the few things that GM got right on the older coaches.. Lot's
of tar like goo sprayed everywhere....It works..

I used the same stuff on the rear cap area on my MC9 last year, no leaks and no condensation problems inside now.

[Nick Badame Refrig/ACC]

Hi Paladin,

Sika is great stuff as well as Automotive Seam Sealer for leaks..

Important:: Which ever you choose, make sure it is "Paintable" if you plan on a paint jobe when your done.  [no silicone]

Also, seamsealers will attract dust and dirt if left un painted for extended pieroids of time.. then you may have doubble work..

Good luck
nick-

[Dreamscape]

I did a search on 3M 5200, nothing was mentioned for sealing/bonding to steel. Am I missing something? It's available at Wally's World is the reason for the question.

[jjrbus]

 I'm looking at your picture and have questions, when you installed the new panels did you use a sealer? I do not see any rivets, did you drill through the original aluminum roofing through the fiberglass and into the tubing and use pull (pop) type rivets? What kind of rivets did you use? Do you plan on reinstalling the rain gutter?

[Paladin]

Hmm, I didn't put the panels on so I'll go by what I know which is little or what I can see:


Use sealer?

It doesn't appear so or at least in all places. I can ask the P.O since I'm in contact with him but I don't know. It's too damn cold to go out and spend much time looking, especially outside.

Rivets:

Not into framing as it appears but the panels are up flush at the upper ends, at least the ones I looked at.
Type? I dunno, large diameter and fairly heavy, some still have to be cut and ground with the tool he gave me. Except for small 1/8" aluminum rivets I know very little of them.


Rain Gutter?

Yes. I don't have one but I want to put one back on. The P.O may still have some parts in his shop.

Remember I've only had the beast for a few months. I'm on the lower end of the learning curve and charging uphill.

[jjrbus]

 The rivets are shavehead, they do not have a hole that can leak like a pop rivet or are there pop rivets also that can be leaking?  I can see no rivets inside in the picture so they are very far apart or into the tubing!  I also do not see any sealer so maybe none was used? very hard not to smear some someplace!!
Couple thoughts one is to pressurize bus this is easily done with a big fan and some plastic and duc tape. Go around the outside with some soapy water and chase down and seal each individual leak. Leaks will show up as bubbles.
Next if rivets are into tubing drill holes in tubing every 16 inch's (from inside) and fill tubing with the canned spray foam. The foam will expand and should fill holes. This is a good thing to do anyway, moisture cannot condense and rust tubing if it is full of foam.
Rivet line should be where rain gutter goes, install rain gutter using butyl rubber tape. There are two types of tape "putty" and "butyl rubber" make sure you buy the butyl.
All of this is without seeing the bus a guess. I am sure there will be other ideas.
                                                                                                           HTH Jim