I experienced the leaking of the entry door on my 2001 320 had it at Kodak several times for repair none of which corrected the problem.
Door seal replaced, extensions riveted to gutter over the door, etc. Water appeared to enter at the bottom of the carpeted area just below the 12 volts cut out switch.
After removing several screws from the door hinge and finding them all rusted I was convinced the water was coming in at a higher level. Placed a garden hose on the roof around the area of the air horn and am FM antenna and the problem could be duplicated removed both the horn and antenna resealed with no luck.
As mentioned the end cap molding appeared tight with no visible openings in the seal. Removed the trim on the column at the inside of the windshield and could visibly see the water coming down the steel structural steel frame starting at the roof level.
At that point, I removed the complete end cap molding and resealed the seam between the roof and end cap silicone sealer and replaced the molding. Have not experienced the problem since. Even though the cap molding looked ok it apparently was the problem. Tom Andrews 2001 U320
Rotting the bottom step from a leaking hinge is a common problem. Many bottom step wood parts have been replaced.
On our coach, we put an additional weather strip on the hinge side of the door. And extended the gutters over the door do direct water away from the door. Any weather stripping you can put on your door will help. We now also have a $10 Harbor Freight water alarm on the bottom step to announce new water entry. by Barry and Cindy 1997 U270 36′
We had our bottom step rebuilt at FT for the same reason (rotted wood.) The tech at FT informed us that it is a “wet step”, since (at least up to 2001), the door doesn’t have a positive seal at the bottom and said to be very careful to seal all around the bottom step with silicone. Dave and Nancy 1999 U270 36′
My 2 cents on the cause of many problems with water entering different places. Every 6 months you must check all trim which covers joints around the whole coach and any in a horizontal position should be checked for caulking that should be along the top edges.
Check that all screws are tight and the area of the roof edges is very prone to leaks and as we all know water goes downhill very easily. SO, make sure there is nowhere for it to enter.
As mentioned before trims around the doors must be fitting right and the water trough above the door needs to be increased in length.
Inside the step area needs to be sealed around the edges too and any water should be cleaned up immediately. On our coach, I found that water had an easy time to follow the hinge and enter that way till I fixed it.
The front cap trim I feel is one of the most important areas to watch for water entry. Screws holding the air horns and a variety of other things up there is another problem that many do not go up and check. Suffice to say every inch of all trim and fixtures should be checked regularly as a coach moves in many directions while going down the road and gaps will happen,& screws will come loose.
It is a simple thing to do but I sense most do not do it. To me, this checking is as important as checking the oil, water, tires. John H
After 13 years, the wood under the steps had rotted and was sagging so much that the step would not close all the way in the “up’ position. My preventative measure will be to run a gutter along the top of the door area and to try and close any gaps in the rubber gasket along the front of the door. It’s a process for sure.