Over the weekend I was cursing Mazda for their wonderful design of the drain tubes on the ND ST. The NC drains were perfect, push a trombone brush from the top, down through the bottom and done. Last Thursday we had heavy rains and Friday I found that the carpet on the PS of the trunk was damp and the carpet behind both seats was wet. So I did some searching on how to clean the drain tubes.....
....I found that the ND has a basket and a sponge filter that you can remove and clean. I did this on both the DS and PS and found the baskets to be fairly clean and gave the sponges a good rinse. Upon completion, I dumped a 1/2 cup of water on each side. The DS was pouring out underneath the car so good to go. However the PS was trickling out underneath and backfilling in the car. So on to step 2, getting access to the drain tube from the top.
To do this, you need to get a flathead screwdriver behind the seat belt extractor to remove a plastic fastener while trying to guide said fastener somewhere where you can grab it so it doesn't get lost and rattle around. Next you have to get something firm enough to clear any clog yet flexible enough to fit under, behind the seat belt extractor and into the drain. For me this was not successful as the wire I was using moved the clog a little but was not firm enough to clear it.
Then I found some pictures that showed how to remove the lower portion of the drain tube from the body so you could clear it from the bottom up. Voila! Got it cleared and after dumping four cups of water on the PS, the water coming out of the drain tube was clear and there was no more backfilling. I attached the drain tube back to the body of the car and dumped an entire cup down the drain. It was now pouring out underneath the car, yay....but wait. I noticed a small trickle of water coming from where the drain tube met the body. I pulled it back out thinking I may have not had it in firm enough. That is when I found that I broke one of the prongs when initially pulling it out.
I applied a small bit of silicone around the entire area in hopes that will stop the trickle.
I finished by wiping everything down that was wet and sucking out the water in the carpets with my shop-vac. I left all of the plastics on the PS removed as I knew it was going to rain Monday and I wanted to check the seal. It poured Monday afternoon so upon getting home, I checked and the the silicone felt a little wet but there was no indication of a trickle as the metal around the area was dry. I am wondering if the silicone didn't fully cure as I didn't think to dry out the inside of the tube before applying and there may have been moisture present.
I checked the upper area of the drain and everything was dry. Next I checked the carpet in the trunk which was dry and then the carpet behind the DS seat....which was wet?! I pulled the plastic liners and the top of the drain area was bone dry but I found some condensation on the lower portion of the metal behind the seat. There is a small section of carpet that covers this, the lower half was wet but the upper half was dry as was the area above it when I stuck my hand up there to feel around. I also pulled the plastic covering the access area to the lower section of drain tube and that was bone dry? I am confused as to where the water came from to wet the carpet behind the seat?
Thus my Monday night was filled with more cursing of Mazda for this ingenious design.