Bus leaks

[nevittja]

We have removed all the bus walls, ceiling and insulation. Now we have found several leaks! It looks like the water is coming in where the skin is riveted to the supports and around the exit windows. Not a lot of water but we need to fix before we go any further with conversion. Any suggestions? Has anyone had any luck with flex seal? Do we take the window out and reinstall? Thanks!!

[FlyboyHPD]

Originally Posted by nevittja

We have removed all the bus walls, ceiling and insulation. Now we have found several leaks! It looks like the water is coming in where the skin is riveted to the supports and around the exit windows. Not a lot of water but we need to fix before we go any further with conversion. Any suggestions? Has anyone had any luck with flex seal? Do we take the window out and reinstall? Thanks!!

Probably two of the best things you can do is to re-paint your roof with an insulating elastomeric rubberized paint. This stuff comes highly recommended.

Insulating roof paint for buses, recreational vehicles


The second thing you could do is to remove all the windows and then re-seal with Sikaflex. It also has great reviews as a sealant to use.

https://www.amazon.com/Products-017-.../dp/B004RCX8XS

I'm going to do both to my bus. Good luck with whatever you choose to do.

[nevittja]

Thanks for the info. We are definitely going to coat the roof. I also found the Silkaflex 221 at skygeek for $7.50 a tube. We still can't figure out some of the random places in the walls that are leaking. Is it possibly for them to leak through the rivets?

[FlyboyHPD]

Originally Posted by nevittja

Thanks for the info. We are definitely going to coat the roof. I also found the Silkaflex 221 at skygeek for $7.50 a tube. We still can't figure out some of the random places in the walls that are leaking. Is it possibly for them to leak through the rivets?

I'm not an expert on rivets by any means. Hopefully someone else here can comment on that .

[Jolly Roger]

Solid rivets usually won't leak because they are friction fit but as your cleaning and sealing all of the seams check the rivets as you go just by looking at them and running your hand over them if some seam loose then yes water can get in.
My leaks were from the windows.
Sika flex is a manufacturers name and they create many sealants. I like one called NP-1 by sonolastic. It performs well, tends to be a little cheaper but still a sikaflex product.
Any of these sealants will seal the body but keep the beads to a minimum thickness or wipe them down to minimum before they dry because the paint won't stay on it. It will look good at first but with age the paint will crack and peel on the sealant.
For the windows you need a good solid bead but the paint isn't going to stay so in one of my lessons learned is maybe I could reccomend picking a sealant color that would match/comparable to what ever your final paint is going to be especially the windows.
I used grey just cause I had access to it and I am still okay cause my bus is still primer grey but after 3-yrs even the primer is giving up so in my mind the darker finish coat is going to do the same thing eventually and then I could end up with (example) cherry red paint with caulking grey stripes at every metal overlap.
Just saying be gentle with the stuff unless your sticking in between the seams as its put together.
Most of the high grade sealants can be smoothed out with a spray bottle and water. Run your bead, spray it and then smooth it. When you do get it on you it loves a plastic bag from the grocery store or some baby oil and a rag before it dries.
Once it dries on you you wear it off.
Just some thoughts/thanges to think about.

[Tango]

Automotive OEM type Seam Sealer is great. Remains flexible, is paintable and bonds like gangbusters. Avail at most any auto paint store.

[nevittja]

Are all the seam sealers the same or is there a particular brand that works better?

[Tango]

There are numerous brands but only a couple that are considered "OEM Grade". One being 3M. Another is McKanika but I have had a lot of trouble with their product not dispensing. And since the "good stuff" ain't cheap...I'd go with a big name. But you will only find this stuff online or at an automotive paint & body supply house. The stuff available at Home Depots & such does not even come close.

[Trask97140]

I used the 3M 5200 Marine adhesive for my windows and rivets. Have a friend who's father is in the fishing business, he swears by the stuff on his boats. Permanent though.

Also used the Dynatron 550 seam sealer on my panels. Seems to have cured up nice, and I believe its paintable.

[Stu & Filo. T]

O'Reileys has it also it's usually behind the counter so you have to ask for it

[GreenThunder]

Originally Posted by FlyboyHPD

Probably two of the best things you can do is to re-paint your roof with an insulating elastomeric rubberized paint. This stuff comes highly recommended.

Insulating roof paint for buses, recreational vehicles


The second thing you could do is to remove all the windows and then re-seal with Sikaflex. It also has great reviews as a sealant to use.

https://www.amazon.com/Products-017-.../dp/B004RCX8XS

I'm going to do both to my bus. Good luck with whatever you choose to do.

I am going to be sealing all of the windows on my short bus this weekend. However, I am in Wisconsin and the temps for this weekend are highs around freezing and lows in the 20s. Do you know if Sikaflex will cure in cold temperatures? If not do you know of what types of sealants would? I was thinking butyl caulk. thanks

[GreenThunder]

Sorry for the post just answered my own question...
Here is a link that has lots of info about sealants for rooks like myself.
MCN - Caulk and Sealant Guide

[DoubleO7]

I would go with butyl tape under the mounting flange of window unit.