Mysterious, impossible leak!

[miarosa]

After redoing my entire 74 Trillium, it seems there is now suddenly a new leak. Water will pool on the seat, coming from Behind the insulation and dripping onto the seat.

I have done:
-The window was just recently resealed with butyl tape.
-The wood around the window never feels damp at all.
-The marine headliner covering the reflectix insulation never has any water dripping down it.
-All screws on the window were double checked to make sure they were tightened.
-There is no water entering by the read headlight or the small runner light.
-I caulked the rivets in the belly band, still leaked.
-Removed the belly band, it is now fiberglassed over with epoxy+glass mat, covered with fiberglass bondo. Shockingly, the belly band gap was already filled in when i took it off! So I thought it was just the rivet holes, many missing, that was the cause. The leak is muchhh lessened now, as I rightfully assumed most was from the belly band holes. But it is still dripping onto the seat.
-Did water test with water below the belly band. Still leaks.
-Ripped up the insulation to about 6" from the seat. It appears to only be damp about 3" up. Fiberglassed the crap out of the wall 6"above the seat, and 6" below the seat, because i'm about to set the camper on fire and I'm out of ideas.

Is it possible that in some insane way water is leaking THROUGH the wall? There are no holes on the outside, I just sanded and painted it weeks ago. There are no visible cracks or anything to indicate a spot for water to enter. The water appears to enter the camper wherever on earth it is coming from, moves down the wall Behind the insulation, drips out onto the seat, and along the wall below in the cubby, on the pontoon, on the floor.

Could the seat pull away from the wall and cause some stress cracks? Something has to give. I'm insistent on solving this.

[miarosa]

I believe its the same leak. The water just runs from above the seat, onto the seat, as well as behind the actual fiberglass bench and down into the pontoon. My headliner is flush with the seat, insulation stops at the top of it. so possibly why it can go both places. The seat is fiberglassed to the shell in some parts, but there is definitely a 1/8-1/4" gap from the seat lip vs the shell wall. We only have one water hatch, which is far away from the point of this leak and has shown no leaking. The lights show no sign of leaking. Maybe it is pinhole leaks, but I feel that would have been evident on the gel coat when i sanded it, and now seen in the paint.

The belly band did not have the metal plates removed. The gap was sealed with what looked like fiberglass epoxy resin. I fiberglass matt'ed the entire belly bad, double layered over the rivets- the tops were removed. Then fiberglass short hair bondo was layered over that. I'm in the process of smoothing it out, as this was a much different task than I anticipated with just filling the gap, and either leaving it just painted, or using automotive trim- to be decided. There is no silicone as I removed the pound of it someone had put under the belly band prior. I have fiberglassed a few holes, and some large, in this trailer. None of them leak.

I feel like I'm going crazy Lol I just don't want my camper to leak.

[John in Michigan]

We spent 3 years finding and fixing all of the leaks in our Trillium 4500. We would fix a leak or two by systematically testing with a garden hose before and after repair. Then later find another leak while camping in a heavy rainstorm.

[John in Michigan]

If you have leak tested the belly band, every through hull fitting such as electrical port and fresh and grey water ports, behind every window flange, etc, here is another thing to check:

I found water entering at factory seams and joints in the aluminum window frames. I have fixed these leaks with sealant.

[miarosa]

Originally Posted by John in Michigan

If you have leak tested the belly band, every through hull fitting such as electrical port and fresh and grey water ports, behind every window flange, etc, here is another thing to check:

I found water entering at factory seams and joints in the aluminum window frames. I have fixed these leaks with sealant.

I have not looked very hard at the inside of my window frames. When pulled for resealing, everything seemed good with them. But i'm for sure about to go check them all now. Thanks for the suggestion!

[John in Michigan]

I found that with difficult to trace leaks, garden hose testing must be done with someone inside watching closely while the person outside sprays.

[Darwin Maring]

do you have a TV antenna?

[miarosa]

Originally Posted by Darwin Maring

do you have a TV antenna?

nope

[Darwin Maring]

Lift one side up higher so the water runs off the other side. If U still have the leak, do it with the other side. Then lift the front up higher so it runs off the back. This might give you a starting point which side the water is coming in from. Good Luck

[Island Claire]

You have not mentioned checking the roof. Our roof vent was the cause of one of our leaks. The other place to check is your awning rail. It is riveted in place.



Good luck. Chasing water is never easy because it never stays at the point of entry.

[miarosa]

No awning. I can't figure out how it'd be the vent, it's quite far from the issue, vent is never wet, no drips on floor, no wet by walls closest to vent, ect.

I believe it was part belly band, and part window frame itself.

[Island Claire]

The water ran behind our ensolite down the wall and onto the bench.

[miarosa]

Originally Posted by Island Claire

The water ran behind our ensolite down the wall and onto the bench.

From the vent all the way behind the kitchen area to the bed area?
Luckily, I have no wetness or trace of leaks there. The vent was replaced and resealed at the same time as the windows, including sealant on the roof.

[TZBrown]

Here is a very expensive way to positive pressure your unit, and then bubble test for leaks. https://rvleaks.com/sealtech-430-r-rv-leak-tester/

With a "large bit" of DIY and a furnace squirrel cage fan you can somewhat duplicate the machine.

Water leaks are a real pain to pinpoint

[Darwin Maring]

TZ Brown - You have the answer.

[mszabo]

Smoke test.

[jokra]

Remember that these trailers are over 45 years old and were probably not designed to last that long, which is why we have to maintain them probably as long as we own them. Every time we take them on the road, the bodies move because they have no frame. In my case, I have the T4500 and it has a lot of extra drawers and other optional things installed, all of which reduced the integral strength of the vehicle. Also, I think that the walls and especially corners were not as strong (well built) as earlier models. I personally don't believe that the wood they used for the window frames were strong enough to last 45 years. I had mine all sealed 5 years ago but found a new leak on the front window area just recently. A few years ago, I found a really nice Airstream that was for sale near the Ocean and when I went to buy it, found that the salty air had caused all the rivets to decay...

[matthfam]

Originally Posted by miarosa

After redoing my entire 74 Trillium, it seems there is now suddenly a new leak. Water will pool on the seat, coming from Behind the insulation and dripping onto the seat.

I have done:
-The window was just recently resealed with butyl tape.
-The wood around the window never feels damp at all.
-The marine headliner covering the reflectix insulation never has any water dripping down it.
-All screws on the window were double checked to make sure they were tightened.
-There is no water entering by the read headlight or the small runner light.
-I caulked the rivets in the belly band, still leaked.
-Removed the belly band, it is now fiberglassed over with epoxy+glass mat, covered with fiberglass bondo. Shockingly, the belly band gap was already filled in when i took it off! So I thought it was just the rivet holes, many missing, that was the cause. The leak is muchhh lessened now, as I rightfully assumed most was from the belly band holes. But it is still dripping onto the seat.
-Did water test with water below the belly band. Still leaks.
-Ripped up the insulation to about 6" from the seat. It appears to only be damp about 3" up. Fiberglassed the crap out of the wall 6"above the seat, and 6" below the seat, because i'm about to set the camper on fire and I'm out of ideas.

Is it possible that in some insane way water is leaking THROUGH the wall? There are no holes on the outside, I just sanded and painted it weeks ago. There are no visible cracks or anything to indicate a spot for water to enter. The water appears to enter the camper wherever on earth it is coming from, moves down the wall Behind the insulation, drips out onto the seat, and along the wall below in the cubby, on the pontoon, on the floor.

Could the seat pull away from the wall and cause some stress cracks? Something has to give. I'm insistent on solving this.

*********


Not familiar with your type of trailer, but have renoed a few trailers, campers, and camper vans.

Does your trailer have a roof vent? Many people replace the seal with butyl and new screws. Not good enough ... Unless you cover the edge of the flange and all screws with a rubber compound or other product, water will seep under the flange and run along the ceiling to the lowest side and down the wall. All my units have had this problem when I bought them.

[miarosa]

Originally Posted by matthfam

*********


Not familiar with your type of trailer, but have renoed a few trailers, campers, and camper vans.

Does your trailer have a roof vent? Many people replace the seal with butyl and new screws. Not good enough ... Unless you cover the edge of the flange and all screws with a rubber compound or other product, water will seep under the flange and run along the ceiling to the lowest side and down the wall. All my units have had this problem when I bought them.

yup. its sealed on the top and butyl taped. doesn't leak.

[bigangelman]

I had the heck of a time finding a leak in a motorhome rear fiberglass cap that we had. I had previously redone the roof and all the caulking up top and I still had a leak. It turned out to only leak while driving in the rain. The clearance lights had a bead of caulk on the sides and top. The suction/ vacuum created while driving would draw water up from below the lights. I replaced the lights with new gaskets behind and no more leaks!