How to keep water from getting in floorboards on a Mercedes S550 W221 Series

Be sure to check out www.s550mercedes.com/ for more repair tips on the W221 Mercedes S550.
This is how I fixed a flaw Mercedes Benz engineers put on the W221 in 2013. It may be the same from 2007 all the way to 2013 but I cannot be sure. This is a 2013 model S550 which is in the W221 Series. What happens is, they put a rain gutter type system called a COWL just below the windshield under the hood where the windshield wipers are mounted. There are 4 drains there along the COWL. The two in the middle drain out below the car but the two on each end just above the front tires on both sides were designed to drain out a small hole behind the front tires. Problem is that these drain tubes will get leaves and other nature debris in them and clog up. When clogged up, they will overflow all over the firewall and the water will find its way through body seals and grommets along the firewall. Many experience a puddle of water in their front and rear floor boards as a result. So what I did was I pulled back the front fender wells and put a 13 inch piece of 1 1/4 clear tubing extending the drain tubes. They now drain out beneath the car instead of where they were. Because they were tucked into a small pocket on back of fender well which had a small hole for the water to drain out. That small hole basically collected any leaves and dirt that made its way down the drain tube and would cause a clog. If you don't park your car inside a garage and there are trees nearby, you'll want to do this.
UPDATE: I extended the clear tube through a hole I made in the road cover, this way I can get my Kobolt blow gun up in it from under the car and blow out the drain from the bottom upwards. Anything in the drain tube will come flying out the top. Lowes sells a Kobolt blow gun with a beveled blue metal tip and it fits perfectly in the tube I used so when I blow it, all the air goes up.
Watch my other video linked below that explains where all your drains are and further discusses why you want to keep them free of leaves. The Mercedes Benz S550 has sort of a waterfall and one of the drains keeps the waterfall from flowing into your floorboard on the passenger side. But it only becomes a waterfall if you let that one drain get clogged up.
Learn about the waterfall here:
• How to Clean Cowl Drai...

[@ericeric7252]

Good tips ! Thank you from France

[@MercedesMechanic]

You are very welcome. Once you modify these drains with the 1 1/4 inch tubing, you can then blow them out from below the car. I use a Kobalt air compressor blow gun with a beveled blue tip on it that fits perfectly in the end of the 1 1/4 inch tubing and do short blasts of air, anything in them will blow out the top.

[@MercedesMechanic]

@@clabruno From my local hardware store, they sell it by the foot.

[@MercedesMechanic]

Be sure to check out www.s550mercedes.com/ for more repair tips on the W221 Mercedes S550.