Roof is still leaking

[RanCarr]

My husband has spent endless hours applying liquid rubber on the roof of our Class-C. Four coats so far. He replaced and sealed all the vent covers and redid all seams... over and over and the +*&^%$# roof is still leaking. We're at a loss as to where to go from here. We don't know where the rain water is coming in from. We cannot get the roof to stop leaking. This RV is turning into a money pit and we're regretting we bought it.

Any ideas, thoughts, advice....?

[YC1]

Where are you getting water? An rv can leak in the front corner and show up in the back corner. Exaggerating a bit to make a point. On a C the front window above is often the culprit. Especially if you park with the front down a bit. Then all of the water goes over the front windshield. I would never have a mh with a window up there again. For emergency diagnosis use some duct tape over the top edge of the window. Dry above and inch or two and let the tape bedcome a shingle over the window. For the side windows do the same. If this stops the inflow you can then repair it properly which may include removing the window.

Vents on the other hand can be a pain as well. One mfgr has a foam gasket that goes under the edge of the vent when you install them. I found the gaskets seem to compress in a couple of years and then allow leaks under them. I remove the gasket material, clean the edges spotless and apply some Dicor along the edges and over the screw holes. Then insert the screws and tighten slowly to let the Dicor press out. Once done all the screws are recovered and a nice bead over the edge of the vent cover.

Air conditioners have to be checked too. There may be four long bolts holding the ac down. Remove the inside cover and check that area out.

If you have slides you can use the same diagnosis method of placing tape over the edges.

[BFlinn181]

You might try closing up the RV and put a fan in a window blowing in to pressurize the interior. Then put soapy water on seams and suspected entry points and watch for bubbles.

[wildtoad]

I second the note on checking the roof AC seal. I had a '88 Winnebago that I unfortunately bought well used and the previous owner had used some form of sealant around the base of the unit instead of replacing the seal. You could not see water on the inside near the ac but all the water ran onto the fridge, rotted the floor under it. As others have said where it shows up may not be where it comes in.

[tomwalt]

Penetrations in the side - like antennas and marker lights? Water can get on a wire or internal part and travel several feet.

[Conquest102]

I agree with the AC check the screws inside. Mine turned several times seemed to take of 1 of my leaks. Also on the front glass check the bottom where glass meets the rubber mine had dryed out and shrunk away from glass. Also top of marker lights they are BAD for leaks.

[TXiceman]

Check the awning attachments points top and bottom. Also check the A/C gasket. if it the original, you would be better off to jsut replace it.

Ken

[fletch460]

Agree with Conquest, without knowing where its showing up, I suspect marker lights. They drill about a 1/2 " hole and run the wires. I found mine right after a rain. Went out and checked and saw water in lens.

[bdpreece]

Take it to a Sealtech shop Sealtech Manufacturing Inc. - RV leaks bubbles recreational vehicles
they can pressure test it and find all the leaks.

[HeapBigEngin]

These are not criticisms....just trying to help 'cause I've been where you are. Seems you are convinced that the roof is leaking, although you do not say how you determined that. You also did not say where the water is appearing inside your RV. And that is important. After 4 attempts on the roof, I think I might look elsewhere. You did not state what method you've used to identify the roof as the source of the leak. We all know that water leaks can be frustrating and difficult to find sometimes.

A method I have used in the past is fairly simple. Start at the lowest point on a vehicle and go up. Also, if there is ANY slope at all to the vehicle, start at the bottom of the slope and move up. Mark off and do small sections at a time. And allow the water time to "run". As you do each section, pay particular attention to the ususal suspects....joints, seams, mating surfaces, missing/broken caulk, etc. Look for an opening at the bottom of a seam or joint that may have opened to allow water in....but may not be readily visible.

I have found too frequently that the slightest (and often overlooked) opening can let in enough water over time to become a major problem. But, for these tough ones, unless you use a system of some sort and allow adequate time, you may end up chasing the thing for a long time.

Please let us know how you make out....it will be very helpful to the rest of us. Thanks.

[2003coachmen]

You need to have your motorhome pressure tested. My Coachman leaked on the left corner of the roof. The Rv place pressured the inside and then soap tested. There were more leaks than imagination tai lights sliding windows,around the outside compartments,water supply door,etc.
A friend has a Holiday Rambler the same company found the mirrors leaking where the mirror is attached to the mirror arm. He had tried to find this leak almost all summer.

[ksg5000]

Time to pressure test - last time I was in camping world they were charging $99 - should eliminate the guesswork.

[SarahW]

Originally Posted by ksg5000

Time to pressure test - last time I was in camping world they were charging $99 - should eliminate the guesswork.

I was going to ask how expensive the pressure testing is. Thanks for the info.

[RanCarr]

Originally Posted by YC1

Where are you getting water? An rv can leak in the front corner and show up in the back corner. Exaggerating a bit to make a point. On a C the front window above is often the culprit.

It would have to run uphill for any leaks from the front window to come through in the kitchen and bedroom in the rear. The RV is parked slightly downhill, front lower.

Especially if you park with the front down a bit. Then all of the water goes over the front windshield. I would never have a mh with a window up there again. For emergency diagnosis use some duct tape over the top edge of the window.

What about the rear bedroom and kitchen leaks? I don't think water will run uphill.

Dry above and inch or two and let the tape bedcome a shingle over the window. For the side windows do the same. If this stops the inflow you can then repair it properly which may include removing the window.

The windows are all BELOW the ceiling so any leaks from the windows would have to run straight UP to come down from the ceiling.

Vents on the other hand can be a pain as well. One mfgr has a foam gasket that goes under the edge of the vent when you install them. I found the gaskets seem to compress in a couple of years and then allow leaks under them.

These are brand new vents with new seals and they're sealed with Eternabond. All the old bond was removed before installing them.

I remove the gasket material, clean the edges spotless and apply some Dicor along the edges and over the screw holes. Then insert the screws and tighten slowly to let the Dicor press out. Once done all the screws are recovered and a nice bead over the edge of the vent cover.

They're all covered - that's what is so frustrating.

Air conditioners have to be checked too. There may be four long bolts holding the ac down. Remove the inside cover and check that area out.

That was already done also. We had to buy a ring to lift the A/C above the roof since that leaked also. That's all been sealed and no more dripping from there. We've spent a bundle on the roof alone and he was so careful to do things right, and the damn thing is still leaking, just not as bad. He's getting disgusted with it and we're leaving soon for 3 months in FL. So we pulled a huge tarp over it, including covering the window in the sleeper area over the cab.

If you have slides you can use the same diagnosis method of placing tape over the edges.

Thanks, what about the roof leaks? So far we seen no leaks from the windows which are all below the roof. Looking close at the windows it appears they were resealed sometime in the past. We pulled out and resealed two of them above spots that were rotten below them. We thought the leak in the kitchen was from the kitchen window, but it wasn't. It seems to be dripping from the bottom of the cabinet above. It may be coming from a brand new well sealed vent about 6' away.