Author Topic: Finding Rain Leaks  (Read 3864 times)

Bill Drout

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Finding Rain Leaks
« on: January 16, 2019, 07:43:43 PM »
I'm the proud (relatively) new owner of a 1998 Patriot Beaver Monticello that I purchased back at the end of August of last year.  She's a work in progress.  One of the issues I discovered shortly after purchase was the presence of one or more rain leaks up by the Pilot Seat on the drivers side wall of the cab.  I removed the TV directly above the pilot chair, and can see quite a bit of staining at the very top of the cab against the driver's side wall of the vehicle.  Is a leak in this location a common occurrence, and if so, what is the likely culprit?  Is there a way to remove the wall fabric without tearing out the cabinets?
Bill Drout
1998 Beaver Patriot Monticello - 40'
CAT 3126B

Karl Welhart

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Re: Finding Rain Leaks
« Reply #1 on: January 16, 2019, 08:54:48 PM »
Bill, welcome to the BAC and our forum.  Many great people here to help you.  Yes, this is a very common problem.  Several places to look.  Front cap marker light lenses may be cracked or just leaking around the edges.  The other area to look is the front cap/side wall seams (45 degree trim piece) along with all the roof/side wall seams (roof gutters).  The TV antenna (Bat wing) can be a source for this leak.

Water can be leaking far away from were you notice the leak on the fabric.  Yes, you can cut out the fabric behind the cabinet with out removing the cabinet itself.  Just cut with an knife blade and pull it out.  However, the fiber board behind the fabric will be stain like the fabric.  That cannot be easily removed without removing the cabinet.  That backing board is glued to the frame structure of the motorhome.

Good luck,
Karl and Nancy Welhart, F36017
2014 Tiffin Allegro Bus 37AP (2014-current)
2002 Patriot (2002-2014)
1997 Monterey (1997-2002)
Niceville, Florida
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Steve Huber Co-Admin

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Re: Finding Rain Leaks
« Reply #2 on: January 16, 2019, 08:54:54 PM »
Bill,
Looks like the leak is above the window and windshield. I'd suspect the front clearance lights or the rain gutter/roof seam. Be sure the clearance light lens are not cracked and that they are sealed to the body with silicon (Lexel is better). If the rain gutter or roof to body seam is covered with a vinyl strip, peel it back and seal the screws or rivets with silicon/Lexel. If screws, consider removing them and adding silicon/Lexel to the hole before replacing them.
Steve
Steve
2015-          07 Contessa Bayshore C9,  400 hp
2013-2015: 00 Marquis Tourmaline, C12, 425 hp
2005-2013: 01 Contessa Naples, 3126B, 330 hp
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Bill Drout

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Re: Finding Rain Leaks
« Reply #3 on: January 16, 2019, 11:10:58 PM »
Thanks for the info and the quick response! 

Yes, the leak is definitely above the windshield.  I already replaced and sealed all of the front clearance marker lights since the originals were full of cracks.  I'm still getting some water in the interior, but I think it's less than what I was originally seeing.

I'll check that gutter/seam that both of you mentioned.  I have a feeling that it is a contributor.  It appears that a prior owner has already used silicone there, but it's possible that it is still not water tight. 

Also one of my FIAMM air horns doesn't work and is non-serviceable, so I'm replacing both of them with Hadleys.  I may be killing two birds with one stone as I was suspicious of the horn mounting since the Dicor had significant cracks. 

Is there a way to more proactively detect leaks?  The interior is really nice and I'd like to keep it that way.  I'm thinking something like a water detector that you can put in a basement in case a sump pump fails or in the catch pan that surrounds the water heater in an attic.  Deploy several of them in areas that already have had leaks.  That's one option, I suppose, but I was wondering if there's another option which one of the RV veterans have come up with that's a better idea  :)

Last question:  What is the best way to check for leaks?  I had one one friend suggest using an oscillating lawn sprinkler up on the roof.  I hate introducing more water if I haven't caught all of the leaks, but I don't know of any other way to do it.

Thanks again for your help!!
Bill Drout
1998 Beaver Patriot Monticello - 40'
CAT 3126B

Lee Welbanks

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Re: Finding Rain Leaks
« Reply #4 on: January 17, 2019, 12:43:15 AM »
Get on top and take a very close look at all places where anything goes through the top and how it is sealed, a minor looking crack in sealant can leak a bunch. I had a leak at one of the air horn bases that allowed water to enter the right front of the coach. The self leveling seal seems to work the best.
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Joel Ashley

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Re: Finding Rain Leaks
« Reply #5 on: January 17, 2019, 03:33:38 AM »
Bill, to back up Steve’s recommendations, I’d suggest a trip to a local Ace Hardware for a squeeze tube of Lexel, usually found hanging from a peg above the caulking supplies.  A caulk gun version is also available if you expect to use a lot;  I use it whenever drilling holes in my house siding, etc., also.  Lowe’s usually carries at least the gun-size version, but not always the convenient squeeze tube. 

The squeeze tube is handy for sealing anything... I use it for water-proofing in-motion Xmas light control modules for example;  the only glitch is after first use, if not effectively capped and much time passes, the product tends to get viscous in the nozzle and the first inch or so thereafter is difficult to work with.  Otherwise it is a superior sealant that’s even non-conductive, and I’ve used it to encapsulate certain corrosion-susceptible outdoor, low-voltage electrical connections.

Our Beaver’s windshield brow trough developed severe cracking years ago, and water appeared to an inch depth in the 12v electric bay, street side forwardmost.  Filling the cracks with Lexel, with touch ups biannually, fully stopped that problem... you certainly don’t want water in that particular bay.

A moistened finger can also help cleanly spread Lexel beads around your new clearance lamp covers also.  Replacing the cracked ones should’ve been a best first step in addressing your leaks.  Of course, make sure all surfaces are clean for maximum adhesion.  I also now regularly use Aerospace 303 on the clearance lights to help prevent UV deterioration.

Joel
« Last Edit: January 17, 2019, 03:39:33 AM by Joel Ashley »
Joel and Lee Rae Ashley
Clackamas, Oregon
36.9 ft. 2006 Monterey Ventura IV, aka"Monty Rae"
C9 400HP Cat
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Jerry Emert

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Re: Finding Rain Leaks
« Reply #6 on: January 17, 2019, 04:38:21 AM »
I just redid my clearance lights last week. The first time I did it I found that the insulation behind one of the lights was soaked so I check them frequently.  If you use lexel be aware that it is very difficult to clean any smears or "oopses!"  I made the mistake the first time I used it of thinking that it would clean up like regular caulk.  I use rubber gloves now and the wet finger Joel suggested works well.    Everytime I use lexel now I tape off where I don't want smears with blue tape just like I was going to paint.  Good luck and I hope you find the culprit!
Jerry, Chief USN Retired
2003 Patriot Thunder Lexington 40' 3 Slides
C-12 Ser#  2KS89983
4000MH
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Doug Allman

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Re: Finding Rain Leaks
« Reply #7 on: January 17, 2019, 12:57:53 PM »
Another place to check is under the A/C units. Several have posted about finding leaks there and replaced the gaskets.
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Bill Sprague

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Re: Finding Rain Leaks
« Reply #8 on: January 17, 2019, 03:50:24 PM »
Our '04 Monterey, when the conditions were right, would produce condensation in the front cap.  It would pool somewhere and drain in the dash area when we left the parking spot. 

"Last question:  What is the best way to check for leaks? "

Regarding the search for leaks, there is a system that (gently) pressurizes the inside of an RV through one of the ceiling fans.  Then soapy water is sprayed on the outside so you can look for bubbles.  The brand is "SealTech".   RV service centers all over the USA, including Beaver Coach Sales, have them. 

I think a YouTube search will provide some DIY versions that incorporate a leaf blower to provide the pressure!  I have no idea if that would work!  But, it would be fun to watch.

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rick Kirchner

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Re: Finding Rain Leaks
« Reply #9 on: January 18, 2019, 06:08:31 AM »
I was about to post a separate topic but I'll just add to this one.  When in NC the beav went through one tropical storm and one class 1 hurricane.  It rained 80" the first year.  I'd had a windshield leak and cured it by carefully running a bead of very thin clear RTV designed specifically for windshield sealing along the black molding.  While up there I found and removed the copious amount of yellowed silicone that the previous owner had used to try and solve the problem (and not disclosed). 

On two occasions I had to remove the sunshades and the cap headliner so that it would dry out.  A dead giveaway are rusty screws holding stuff in place.   

The rain in NC was just too much.  Spent the first two months sealing the gutters and rivits with marine polyurethane.  Dug out all the sealant aeound the recessed awning and re-applied.  Still leaked in and bubbled the wallpaper behind the passenger seat.  On the drivers side, water ended up on the switch panel and swelled the OSB there.  The electrical bay carpet was soaked and the fasteners very rusted.  Brown stains appeared on metal below the beltline, I finally figured out it was glue residue from in the wall.  I finally found covered storage.

Now back home in the Mojave, I was happy to run the fans and just let the coach really dry out in the single digit humidity.  But you may have heard it has been raining a lot this week. 

Drove to Cal Speedway today and just outside of home base I noticed the voltage gauge flickering, then the shifter panel dimmed, the fuel consumption on the silverleaf seemed excessive (and static).  I thought it was just a problem with the step, which has been acting erratically, constantly cycling when the engine is running.  I crawled under the coach on the shoulder and unplugged it, no change.  Told DW that we'd try to make the gas station in Randsburg where I could spend more time troubleshooting.  I was also worried about the alternator - that maybe I screwed up something in my re-design in getting rid o the leese-neville, but both batteries were over 14V and the Delco was putting out 14.6 or so. 

About 5 miles outside of Randsburg the problem started to clear up and I figured it out - water got in the electrical bay again and that's where the transmission controller is.  I had the trans change from 6 gears requested to 4 when in 4th pulling the hill, some more random dimming, and then the trans wierdness and the fluctuating voltage finally cleared up.  Silver leaf displays returned to normal too.

When fuelling up I checked the bay - soaked.

So I finally figured out the water has been coming in the vertical moldings over the cap joints on both sides.  Have a cube heater in the bay to dry it out.  Now I can finally fix the dang thing. 

Have to fix that dang step too!


George Harwell

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Re: Finding Rain Leaks
« Reply #10 on: January 18, 2019, 12:25:45 PM »
Water leaks can drive you to drinking. I fought leaks on my 03 Monterey for over 10 years. Applied 4 inch ETERNABOND tape to the front and rear cap seams, no leaks since. Got the tape on Amazon. BTW, can be applied over the old sealant. Just make sure it’s cleaned thoroughly.

Mike Shumack

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Re: Finding Rain Leaks
« Reply #11 on: January 18, 2019, 01:07:31 PM »
That Sealtech idea is pretty neat. https://rvleaks.com/

I think you would need "a lot" of air pressure inside the coach to find small leaks because it will always leak some air at the room slideout seals.

https://www.youtube.com/watch?v=5TvG9-CBTg4

Does this actually work or is it a gimmick?

rick Kirchner

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Re: Finding Rain Leaks
« Reply #12 on: January 18, 2019, 03:02:02 PM »
I believe there's one that also uses a smoke generator.  much easier to find the leaks.

Bill Lampkin

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Re: Finding Rain Leaks
« Reply #13 on: January 18, 2019, 09:27:44 PM »
I noticed the floor in our front run bay was wet, told the dealer. He crawled under the MH and used that expanding foam sealant on the wire bundle where it exits (enters) the bay (bottom right). All dry now! Since the FRB is just ahead of the wheel well, I think spray from the tires was driving the rain in through that wire bundle. 
2005 Patriot Thunder Lexington, 3 slides
40' tag axle (short wheelbase)
525 hp C13

"Goin where the weather suits my clothes..."

Bill Sprague

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Re: Finding Rain Leaks
« Reply #14 on: January 19, 2019, 12:36:38 AM »
Over the dozen years we had the Monterey and participated on this forum, I think I've written what would add up to a short book about various water leaks successes and failures.  In the end, it was pretty dry and watertight.  I hope Rick still finds it that way!