Because any vehicle that does not have a permanently sealed top (as would say, a Camaro or a pick-up truck) is prone to leakage, a system by which water can leave the inner frame body of your car was engineered by Mazda in order to keep the poor thing from rusting away. It is important to maintain this simple system - unless you enjoy destroying cars.

The main drains are just behind each of your seatbelt towers. At the back of your package shelf (that thing that's behind your seats that the soft top lies on when it is down), near the rear window, you will see button-like clasps. Carefully remove these (don't worry if they break - it's not very hard to find replacements for them) and keep them somewhere safe so as not to lose them. Now carefully pull back that upper portion of your carpet kit (Miatas have a two-piece carpet kit - one piece goes along the package shelf and meets with the other portion just behind the middle of each seat, and that piece runs along the remaining length of the car - cut to fit over the transmission hump and gear shifter), being careful not to ruin the insulation that was merely glued on at the factory. This job is easier to do with the top down - you can maneuver the top is such a way as to expose the holes I am about to finish describing this way.

Just behind your seatbelt towers (where the chest belt rolls up into a little black box) is a blackish square "bowl" of sorts. That bowl is to catch water which runs off the top of the car and onto the outer railing, then through the rain rails and into this collection bowl to then be carried down a long tube running from behind the seatbelt towers all the way to the bottom of the car. Inside this bowl you will find a circular indention that marks the beginning of the drain tube. Many folks, myself included, merely straighten out a clothes hanger and carefully feed it into the drain holes - make sure the hanger does not have any sharp bends, as the drain tubes are made of a rubber-type substance and will likely tear if you are not at least a little bit careful. Once you have extended about two and a half feet of hanger, stick your head under the car just below the top of the drain hole - what do you see? Yup - the other end of that hanger, and probably some water if you're really lucky.

So this is how the Miata drains from top to bottom. Should these drain tubes get clogged, you will likely have seepage into the cabin of the vehicle, which will in time cause mildew and worse - rust. I clean my tubes once a month during rainy season, once each summer. A way to eyeball the drain to make sure it is working correctly is to take a garden hose and just run water all along the outside plastic rain gutters (all along the bottom edge of the convertible top). Check below as you would have to see that hanger and make sure that the water is running clear and easy underneath the car. This usually lets you know whether or not it's clogged up in there.

So we know how Miatas drain from the top, but what about from the bottom up? Believe it or not, our cars being so low to the ground makes even a shallow puddle a possible problem. Up-splash from the roadways can cause damage to the car if there were not yet another system of drains in place. Next to each of the four jack points on the Miata are two reinforced slits where water drains back onto the ground (four per side of the car). These often get clogged - especially in the earlier M1s, and need to be freed of debris from time to time. I used a small paper clip, then a large one, to poke up in there and wiggle loose the gunk and road grime that had found its way in there and clog up my drainage. I have had it recommended to me to use a drill with a small bit to enlarge the holes. Post-94 models had larger holes, which has pretty much eliminated the problem altogether.

So that's how water drains away from the car. Of course, some say that if you go fast enough the water won't get in there in the first place. I do not recommend this procedure. Though only preventative maintenance, keeping your drainage paths clean and clear can prevent you from certain body damage later on in the car's life.

As always, if you have any questions or comments on this or any other article I have written for our club, feel free to email me at DMCtech@weatherwax.net. Happy New Year everyone - keep the shiny side up!

Bonni

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