Leaky cabover (1996 Tioga Montara, Class C)

So, our motorhome has a small problem. The cabover leaks around the base by the bed and some of the wood is slightly soaked and might start (or have started) rotting. We have googled what to do and the result we got was eternabond. Some sort of sealant tape.

Please respond with your tips and ideas. Also if you know anything about the cost of fixing it please let me know.

thanks

I traded in a 1996 31Z about three months ago that had the same problems as yours. During the two years that I owned it I recaulked the entire roof and later put Eternabond on all front and rear seams and around every device which protruded through the roof. I also replaced all of the running lights with new ones and caulked around the lights and on top of the lens hold down bolts. The lens hold down bolts are actually the lights' ground so if you replace a bulb, the lens or the entire light make sure you don't twist off the bolt or pull it through the roof.

Your immediate problem is probably the cab over front window leaking. As you read the forums you will see where some owners have eliminated this window because of potential or actual leaks. In my opinion, that is the ideal fix, however, pulling the window and reseating it with new materials is a more straightforward procedure for a novice like me. The real problem with this window leaking is that the leak is not detectable unless someone goes up in the overhead and actively looks for it.

Also, and for good reason, most of the experienced RVers constantly remind others not to use a substitute for Eternabond.

BTW, my Tioga was solid except for that roof.

Larry

The difficulty with patching this kind of problem is the damage is nearly impossible to stop by just stopping the leak.  Commonly, what happens is water leaks into the bunk structure between the outside Filon (or whatever covering) and the bottom layer of the bunk upper surface.  It's trapped because there is not way to drain.  It can take a long time and a lot of water before the problem gets to the point where you see it as you have reported.  Using Eternabond may well stop the leak, but not the continuing damage (rot).

I recommend you open up the bunk structure to see what is going on.  This can be done relatively easily by cutting sections of the top layer of plywood to expose the interior of the structure.  You should see foam insulation sandwiched between the bunk top and bottom surfaces.  It should be dry, of course, but don't be surprised if you find the insulation saturated with water and much of the wooden framework soaked and/or rotten.

If you are lucky, maybe it will be fairly dry and rot free.  If so, by using space heaters and/or fans you might be able to dry it out and recover the access holes you cut with another layer of plywood.  If you are not so lucky, follow my website link for what I had to do to fix my problem.

In the process of repair, I 1st tried rebuilding and resealing the roof, replacing and sealing the clearance lights, etc.  When that did not solve the problem, I rebuilt it again.  This time I removed the front window and replaced the entire front portion of the rubber roof (about 4') and sealed all joints with Eternabond.

Even after taking those measures, I still found leakage which proved to be water getting in through the two small side windows in the bunk area.  What made it difficult to find was it only occurred when the nose of the MH was downhill (as it is in my driveway) enough to allow the water to overflow the small drains in the window frame allowing water to cross over the ridges the windows slid on.  Luckily, when I rebuilt the bunk area the 2nd time I made the bunk top surface removable so I could inspect for water penetration after a hard rain.  That little idea saved me from having to rebuild a 3rd time or blow it up.

I had the same problem with a '95 Tioga.  It leaked around the same area.  I had a repair shop open the front panels where they meet in the front (the problem and since corrected by Fleetwood to a one piece front cap).  Inside, most of the wood frame was wet, damp and dry rotted.  We buttoned it up and I traded it in on my present '99 Bounder.

I had leaks at the Fantastic Fan, clearance lights and front cab-over window with the inside overhead covering indicating where they were coming from. I also noticed damage on the forward surface of the wood holding the bunk but thought that was a result of the window leaking. I hadn't worked my way down to the possibility of leaks coming from that forward exterior seam. I'm just glad that I got rid of it before I put anymore time or money into it.

chckmlls1 said:

So, our motorhome has a small problem. The cabover leaks around the base by the bed and some of the wood is slightly soaked and might start (or have started) rotting. We have googled what to do and the result we got was eternabond. Some sort of sealant tape.

Please respond with your tips and ideas. Also if you know anything about the cost of fixing it please let me know.

thanks

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It all depends on how bad the damage is. And how much motivation you have to make repairs. If the wood is soft you may be able to use one of the wood-hardening products out there. I have used a product from www.delamrepair.com with success.

Make sure you find and fix the leak. Use a garden hoes to wet the beunk area while someone is inside checking for water. Start at the bottom and worl slowly up the sides.