N, no, no!!! The water in the caller’s miata is NOT coming from the convertible top leaking! There are drain plugs in each side of the car in the tracks under the door. These drain plugs accommodate the run-off of the convertible top as it comes down the side and back of the car and runs down the back. When those drain plugs get clogged with road mud or pine needles or anything else that tends to plug up the drain, then water begins to flow into the floor. It tends to collect in the back and when you step on the brake, it flows to the front. This very thing happened to me with my LeBaron and I finally got the answer from someone on the lebaron listserv. Once we went under the car, located the drain plugs and cleaned them out, we had no more problems with water. We did have to take out the carpets and dry them, but this solved the problem with NO COST! Have him look under his car on each side for those drain plugs!
First, the best place for Miata information is Miata.net, the online home for Miata owners interested in basic maintenance, dropping a V8 in, and everything in between.
Now, the top is not leaking. Instead, the car has a series of drains that channel water off of the top and down to the roadway. These must be cleaned regularly. If the caller were to feel behind the seatbelt tower on the sides of the parcel shelf he would fine two plastic reservoirs with a drain at the bottom that is certainly clogged. Using a test-tube brush, or something similarly long and thin, clean out the drain and the water will find it’s way to the roadway. There are also tiny openings in the pinch welds under the doors that must be kept clean so that water can drain from the front drain system.
Right now water is overflowing the drain reservoir and collecting under the seat where there is a raised ridge that the front of the seat rails bolt to. It will act as a dam to prevent the water from coming into the foot well, until he brakes hard.
Clean the drains, dry out the interior of the car, and maybe clean out under the seats where water has been collecting. Do this now and the car should last for many more years.
Chesapeake Area Roadsters
I wish Tom and Ray would learn a little bit about these insanely popular cars.
Just to add. There is a drain in the rain shield/collecter under the back of the top. The drain is likely plugged and can be fairly easily cleaned. AND there are also drain holes under the rocker panels that sometimes need to be cleaned.
This should be fairly cheap to fix, even at the dealer.
Get it fixed NOW.