UHaul Window Leak - Capillary Action?

[Thomas G.]

Having rebuilt my UHaul windows and taken extra precautions of butyl sealing the top surface of the perimeter seal to fiberglass, I was feeling pretty good about my handiwork. That is until we had an all day rain yesterday and I found a little puddle inside under each side slider.

Today I put a sprinkler outside and got inside to watch the window carefully. I noticed that the fuzzy flocking in the U channel gets saturated almost immediately. This has to be due to capillary action as there is no other way for the flocking inside to get wet, especially that fast. I also noticed that the flocking stands taller that the innermost channel of the window, meaning that water droplets formed at the top of the flocking are free to run over the top of the aluminum channel and inside the trailer.

Has anyone seen a similar issue and if so, how did you correct it?

[theman]

I just did mine last week and rework some issue this WE because I had some water infiltration. It is a lot better than when I got the unit buth still I want a dry sleep. Now I don't have anymore water coming from any seal but I only have the same problem as yours, water coming in from the sliding chanel. Capilary action is exactly how I would call it. I cut every chanel this mornig to get a good draining but stil water is coming up in the channel.

I am still working my head around to find a solution. If you get it before I do please share it

Fred

[Thomas G.]

Originally Posted by theman

............
I am still working my head around to find a solution. If you get it before I do please share it

Fred

I noticed that my rear window doesn't have this problem but the inner wall of the bottom U channels is taller than the other two. On the side windows, all three are the same height. This makes me think that the issue is the flocking wicking over the inner wall. One solution would be to take a razor and shorten the outer side of the flocked channel liner. (But if I'm wrong I've buggered up the channel liner permanently) My current experiment is to insert a thin sheet of plastic sheet between the flocking and the inner channel wall. This sheet is about 1/2" tall overall and sticks up just enough to keep the wet flocking away from the outer channel wall. I hit it with a sprinkler for 1/2 hour today and it seemed to work. I'll wait for another rainy day and see if it continues to work.

Ironically, when I rented a UHaul camper in 1985 I recall the side windows dripping onto my sleeping bag - so maybe it is just a design defect.

[theman]

I look at it today and you are right that might be the problem. I will also try to build a little wall with thin plastic. Keep my update. Thanks

fred

[Perry J]

I'm not familiar with U-Hauls but I just eliminated the same problem on a 1988 Lil Bigfoot
I removed, dismantled reapired and replaced every window in the trailer.
The sealant between the glass and the aluminum window frame had dried and was leaking.
The exterior rubber moulding is not a water seal it's a trim.
Remove the glass from the window frame,clean the old sealant from the glass and window frame.
Apply a small bead of black silicone to the frame and replace the glass in the frame it should eliminate the leakage.
It's a lot of work, but well worth it.
John

[Thomas G.]

Originally Posted by Perry J

I'm not familiar with U-Hauls but I just eliminated the same problem on a 1988 Lil Bigfoot.............John

Thanks John. I think the UHaul is different. It has a sliding plate of glass that rides in an aluminum track on a flocked U shaped run. The sliding glass really can't be caulked - and still open.

[Perry J]

Does it slide past a fixed pane in an outside channel?
I may not have been specific enough it is the fixed or stationary glass that may need to be sealed.
The exterior sliding portion track has weep holes to drain the water. They may need to be cleaned or vene enlarged.
The interior has no drain or weep holes so if the sealant between the fixed glass and the aluminum frame has dried up leaks the water will end up in your trailer.

[Thomas G.]

Originally Posted by Perry J

Does it slide past a fixed pane in an outside channel?

Yes

I may not have been specific enough it is the fixed or stationary glass that may need to be sealed.
The exterior sliding portion track has weep holes to drain the water. They may need to be cleaned or even enlarged.
The interior has no drain or weep holes so if the sealant between the fixed glass and the aluminum frame has dried up leaks the water will end up in your trailer.

OK, I think I understand you now. I just rebuilt the windows with new rubber parts. The weep holes are open. The design is such that even if the fixed glass perimeter leaks, the water ends up in the bottom channel and leaks back out the weep holes.

[Matt in SV]

U-haul used to have weep hole covers that would have helped in this regard - at least they are specified on the part list.

Tiny windowbox shapes that are inverted over the weep holes to draw out the moisture to overcome the capillary effect: Keeps those weep holes clear, too! They might have looked something like the attached, but I don't know if these are the right size??

Hehr Weep Hole Cover H210-027

Hehr Weep Hole Cover-BLACK ONLY H110-444
my web search on weep hole covers led me back to Fiberglass RV!:

http://www.fiberglassrv.com/forums/f...ers-41941.html
Regards,

Matt

[Thomas G.]

Originally Posted by Matt in SV

U-haul used to have weep hole covers that would have helped in this regard - at least they are specified on the part list.

Tiny windowbox shapes that are inverted over the weep holes to draw out the moisture to overcome the capillary effect: Keeps those weep holes clear, too! They might have looked something like the attached, but I don't know if these are the right size??

Hehr Weep Hole Cover H210-027

Hehr Weep Hole Cover-BLACK ONLY H110-444
my web search on weep hole covers led me back to Fiberglass RV!:

http://www.fiberglassrv.com/forums/f...ers-41941.html
Regards,

Matt

Matt, excellent point! I noticed when I was sprinkler testing the windows that the water bridged the weep holes and if I probed the opening I could break the surface tension and water would flow out. If these weep hole covers tend to make the weep holes flow better, that would be great.

I'd swear that some one here said that they put pieces of string in the holes to draw out water, but maybe I'm mixing it up with using trimmer string to clean the holes.

[Perry J]

I'd swear that some one here said that they put pieces of string in the holes to draw out water, but maybe I'm mixing it up with using trimmer string to clean the holes. [/QUOTE]

String or weedeater cord is used to clean the weep holes.
All you need to do is keep them clean and the water will drain out without the decorative caps.