How to seal Leaking Windows?

Ah bummer,

I'm really sorry to hear that. I've heard from a lot who are struggling to keep the water out of their windows, but haven't 100% succeeded yet, so I guess you're not alone! So are you leaking at the corners of the windows between the window frame and the bus? Or are you leaking between the window glass and the window frame?

I reinstalled all of my windows with Butyl tape, and I believe I'm all sealed at that joint (I have a different window design from), but I do have a bit of water intrusion still where the window pane meets the frame. Next step for me is running a bead of seam sealer along that rubber gasket, but I'm considering a polyurethane sealer instead. Maybe like what they use to install windshields. Having trouble pulling the trigger on a product. I hope you get it figured out promptly once it warms up!

Butly tape and dynatron 550 will seal it up, you just have to be precise and thorough.
 
Butly tape and dynatron 550 will seal it up, you just have to be precise and thorough.

Just got home with some Butyl tape and PL window & door poly sealant (auto store only had 1 bottle of 550, and I’ve heard from others that PL works great). Do you recommend putting the tape all around the window frame or just opposite where the original weatherstripping is?
 
Just got home with some Butyl tape and PL window & door poly sealant (auto store only had 1 bottle of 550, and I’ve heard from others that PL works great). Do you recommend putting the tape all around the window frame or just opposite where the original weatherstripping is?
We played around with this. We did butyl tape on the face left and right where the window sits flat against the bus. On some windows we had room for butyl tape underneath it. We used sikkaflex underneath the ones that wouldn't fit with the butyl tape in it. We used weatherstripping at the top of the windows. Many of them need a different amount so I got an assortment of sizes and we use the amount we need in each window. I also put weatherstripping along the top because I had extra. We are going to sikkaflex all around the outside once we are done. I also used butyl tape to even out the weird parts of the windowsill. I'm a little scared to test it.
 
My main window leak issue is now between the glass itself and it’s surrounding aluminum frame. Mostl likely going to use caulking to seal it up
 
DOn't use "caulk" or silicone. Get some real Seam Sealer.
Does the 3M dynaflax or whatever it's called work for that particular application? I got a different brand and didn't care for it. Do you think it would be better than sikkaflex which is an adhesive/sealant?
 
Get the "good stuff". No need for "adhesive" action but you do want something that stays pliant and bonds well. 3M's urethane sealer is UV resistant and what most auto makers use at the factory. Cheap? No. But it works like gangbusters. I am in the process of running over 110 feet of beads with it on my rig. Wear gloves BTW. Any kind of urethane stuff stains the beejeezus out of your hands .



https://www.3m.com/3M/en_US/company...hane-Seam-Sealer/?N=5002385+3293242000&rt=rud
 
I found three places water was getting into my windows:

1) Between the metal of the bus and the aluminum window frame. I used Lexal to seal this. I'm too lazy to take out all the windows and reseal with buytle tape.

2) In the track that the upper window slides in, which is outside the lower window. Again I used Lexal. I pumped it behind the gasket at the bottom of the track. Now the windows don't slide all the way down, but water that gets in that track is forced out of the channel, onto the steel window ledge.

3) Between the glass and aluminum frame. There is a rubber gasket, but it was not sealed tight and in some cases didn't completely go around the entire perimeter of the glass. Here I used silicone. I laid a very sloppy head around the outside perimeter of each piece of glass.

This is after I resealed all of the roof panels, hatches, and vent covers with 3M seam sealer and then painted the roof.

So far so good...
 
3) Between the glass and aluminum frame. There is a rubber gasket, but it was not sealed tight and in some cases didn't completely go around the entire perimeter of the glass. Here I used silicone. I laid a very sloppy head around the outside perimeter of each piece of glass


This is where our water problems come from as well. Right now we've sealed over it with transparent weathersealing tape, but it's temporary and looks it. It wouldn't look too bad if not for the visible condensation under the tape. One of these days we'll lay a bead of sealant over that rubber gasket.
 
I just mounted the windows for the 3rd time only to realized that it wan't my seal job that was the problem all along. The windows were sealed find to the frames of the bus but, like karrlot, water was coming in the aluminum seams of 4 window frames themselves... at the bottom of that slot where the top pane slides down into. Now I need to figure out the best aluminum-to-aluminum sealant to use. I fixed one window with an 2 part epoxy metal 'weld' glue but the second window I used it for still leaks so I am not sure if I failed to get it back in there well enough or if I should try something different. Any suggestions out there?

To seal the window frames to the bus this last time, I used something called "hule cama" here in Mexico. It is a long roll of square profile black gummy stuff that is sticky, stretchy, and plyable. You just form it to whatever you need. It seems to work great to form to the buses irregularities and hold the windows extremely firm once windows are pressed in for a few minutes. Anyone know what that is in English?
 
I just mounted the windows for the 3rd time only to realized that it wan't my seal job that was the problem all along. The windows were sealed find to the frames of the bus but, like karrlot, water was coming in the aluminum seams of 4 window frames themselves... at the bottom of that slot where the top pane slides down into. Now I need to figure out the best aluminum-to-aluminum sealant to use. I fixed one window with an 2 part epoxy metal 'weld' glue but the second window I used it for still leaks so I am not sure if I failed to get it back in there well enough or if I should try something different. Any suggestions out there?

To seal the window frames to the bus this last time, I used something called "hule cama" here in Mexico. It is a long roll of square profile black gummy stuff that is sticky, stretchy, and plyable. You just form it to whatever you need. It seems to work great to form to the buses irregularities and hold the windows extremely firm once windows are pressed in for a few minutes. Anyone know what that is in English?
Sounds like butyl tape to me.
 
I just mounted the windows for the 3rd time only to realized that it wan't my seal job that was the problem all along. The windows were sealed find to the frames of the bus but, like karrlot, water was coming in the aluminum seams of 4 window frames themselves... at the bottom of that slot where the top pane slides down into. Now I need to figure out the best aluminum-to-aluminum sealant to use. I fixed one window with an 2 part epoxy metal 'weld' glue but the second window I used it for still leaks so I am not sure if I failed to get it back in there well enough or if I should try something different. Any suggestions out there?

To seal the window frames to the bus this last time, I used something called "hule cama" here in Mexico. It is a long roll of square profile black gummy stuff that is sticky, stretchy, and plyable. You just form it to whatever you need. It seems to work great to form to the buses irregularities and hold the windows extremely firm once windows are pressed in for a few minutes. Anyone know what that is in English?

Direct translation =rubber bed

I suspect that it is buytl rubber. Something like this: https://www.homedepot.com/p/Fabral-...gclsrc=aw.ds&dclid=COa75KPNld0CFUgLrQYdP6MA6A

Are you in QR?
 
Get the "good stuff". No need for "adhesive" action but you do want something that stays pliant and bonds well. 3M's urethane sealer is UV resistant and what most auto makers use at the factory. Cheap? No. But it works like gangbusters. I am in the process of running over 110 feet of beads with it on my rig. Wear gloves BTW. Any kind of urethane stuff stains the beejeezus out of your hands .



https://www.3m.com/3M/en_US/company...hane-Seam-Sealer/?N=5002385+3293242000&rt=rud
Sikkaflex is like 7.50 a tube and the sealant you mentioned is $32.50 per tube. It does seem to attract dirt (probably the adhesive properties) so that's not ideal but if I paint it I think that should stop. It's supposed to be great, really long lasting stuff. It isn't neat and pretty to work with (I'm not great at caulk to begin with) but the franky the bus isn't going to look that great close up anyway because it's over 20 years old and has several dents and scratches etc. My brother in law is going to come give me Bondo lessons in late September so hopefully that will be somewhat less true soon.

Also, unless it's clear I can't use it on the window around the old gaskets that start pulling away in the corners just a bit. And it seems impossible to replace the gaskets because every one of my windows has the bottom 2 screws rusted in place. I tried and tried and TRIED to get one window disassembled to figure out which parts I could re-use to make whole better windows out of windows that has issues. I cannot get the bottom screws out. I even smashed one window by repeatedly hitting the screw with a hammer and a screwdriver after using pb blaster, WD-40 etc repeatedly throughout the day for several days and still couldn't budge it. They all look the same. Snow probably sat on the ledge in the winter. I am gonna have to do all those lower corners really well to make sure snow and water can't get in there. The design of those windows SUCKS!!!
 
I went to the carwash the other night to wash the diesel off the top and sides of the fuel tank (this whole month has been chock full of
learning experience) and I figured I would see how the windows were holding up.

Boy-howdy, I've got issues! I realize that it is much higher pressure than rain. The water is also coming an angle below the windows, not above. However, there was a lot of water on the wrong side of the window.

I believe some of it came in over the top of the window. I think most of the water came in between the top window, which is on the outside, and the bottom window on the inside. I think I just shot the water right up between the two of them and into the bus.

I never imagined I would be spending this much time and resources on keeping the inside dry.

What has anyone used to seal between the two windows?
 
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I just mounted the windows for the 3rd time only to realized that it wan't my seal job that was the problem all along. The windows were sealed find to the frames of the bus but, like karrlot, water was coming in the aluminum seams of 4 window frames themselves... at the bottom of that slot where the top pane slides down into. Now I need to figure out the best aluminum-to-aluminum sealant to use. I fixed one window with an 2 part epoxy metal 'weld' glue but the second window I used it for still leaks so I am not sure if I failed to get it back in there well enough or if I should try something different. Any suggestions out there?

To seal the window frames to the bus this last time, I used something called "hule cama" here in Mexico. It is a long roll of square profile black gummy stuff that is sticky, stretchy, and plyable. You just form it to whatever you need. It seems to work great to form to the buses irregularities and hold the windows extremely firm once windows are pressed in for a few minutes. Anyone know what that is in English?


In English I believe it means, "good ole black hash."
Try some, you won't care about leaky windows:wink1:
but then again I might be completely mistaken.


John
 
In my bus, 96' Thomas, the emergency exit windows are the worst. I took a Brita and poured it on the seams, and it just gushes in. Need to reseal them and maybe replace with windows from the ones I'm removing.
 
on many of those windows they used felts between the 2 sashes and along the edge of the moving sash.. felts only last so long.. school bus windows are pretty easy to remove and once removed, disassemble.. you can replace the felts in them.. the fizy side of velcro may work.. its a total tedious job to pull them apart and reassemble them.. and its not a sure thing that they will seal 100%.. esp against car wash pressures.. school bus windows almost never see sideways rain... also Most window seals betweenthe window and the bus body are usually gone.. so at the very least its a good idea to remove the windows and replace the seals around the frame..



-Christopher
 
Hi guys,

I am beginning to become frustrated with my Thomas Built Windows! I can't seem to get them to stop leaking at the bottom corners. I have tried butyl tape, caulking them, and now I have tried a roof sealant (which has been the most effective but still not 100% leak proof.

Any pro tips on how to handle these corners? I have applied an excess amount of this roof sealant and water still manages to come through when spraying it with a hose.

I've been doing my water tests as a one man team, I just stick an arm out one window and spray the other window I'm checking. Is this too close of a spray (I'm not blasting it with the jet nozzle).

Not to mention my windows have leaks at the actual glass seals as well. But that's a different problem to tackle altogether.
 
Weatherstripping? Yeah? No? I'm thinking not.

Also, at the bottom of the window and especially in the bottom corners is where the water seems to be coming in. Any idea how to deal with this? I'd planned on using a generous amount of sealer to embed the bottom window frame. Is this a sound idea?

This is where my windows were leaking from. The bottom where the window sits on the frame. When I tore of my wall skins I could see in there and see day light thru many of the corners. The 35yr old calking/weather seal was mostly spent. I would have puddles everytime it rained or the snow melted off the roof.

I cleaned the bottom of the windows and bought a couple of tubes of calking and put a good bead on where the windows sit and filled the corners.

I haven't had any leaking. Have had rain and snow melt, no leaks.
 

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