Water 💦 in Miata trunk! Where it’s getting in.

This video explains a couple of possible reasons why water 💦 May be getting in to your Miata’s trunk (“Boot” for my friends in the UK).
In this case, the trunk had a lot of water in it after a couple days of heavy rain 🌧
I found out that the soft top drains were blocked and water was backing up in to the trunk.
The Miata was parked on the driveway with the nose pointed upwards.
Some other possible reasons for water entering the trunk are:
-Damaged “Rain Rail” (the gutter that catches water that drains to the bottom edge of the soft top).
-Damaged soft top or back window.
-Torn trunk seal / weatherstripping.
-Cracked or damaged tail lights.
-Degraded tail light gaskets.
-Degraded 3rd brake light gasket.
-Antenna mast seal.
-Frankenstein bolt seals.
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More new videos are on the way 🎬
Disclaimer:
Due to factors beyond the control of MiataMan, I cannot guarantee against improper use or unauthorized modifications of this information. MiataMan assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. Use this information at your own risk. MiataMan recommends safe practices when working on vehicles and or with tools seen or implied in this video. Due to factors beyond the control of MiataMan, no information contained in this video shall create any expressed or implied warranty or guarantee of any particular result. Any injury, damage, or loss that may result from improper use of these tools, equipment, or from the information contained in this video is the sole responsibility of the user and not MiataMan.

[@CarBore]

Seeing that rust on the sills makes me worry a bit less about mine 😂

[@davinchi2156]

sameeee

[@bkawbtrs]

Cracked rain rails would be another cause, especially if you notice the deck carpet is damp (repair it or replace with a more flexible aftermarket one). The striker plate that holds the Frankenstein Bolts also has a gasket that could fail (I simply applied RTV on the faying surface). The radio antenna could also have water leak inside, since it has its own drain tube. Finally, check if all the drain holes in the trunk are properly plugged up (mine came with an aftermarket antenna and the drain hole for the original wasn't plugged).

[@MiataMan]

Very good points 👍 Over the years, I have experienced leaks from all of the sources that you mentioned.

[@Beardchanics]

Useful, our one need sorted as well at some point, not getting much in but just enough to be annoying.

[@silverfox__12]

Thank you! Just picked up a 97 M-Edition (auto unfortunately) for my daughter. While detailing it, we found the trunk to be rather wet. Will check these items this evening..

[@dcdad556]

Coat hanger does work to clear the rain passageways. I spent about $7 to buy a trombone brush: about a 1 1/2 inch diameter brush on both ends on a 4-foot cable. Cleans better and on line or at your local musical instruments store.

[@StingrayOfficial]

Thanks for the video. Sadly I found some water in my trunk. Looks like there are a few different possibilities. Wish me luck!

[@shaggyshaggadellic1955]

Haha hahahaha priceless I bought my miata about 5-6 months ago and had noticed all the same leaks and heard about basically every miata except the hardtops had the same issue haha. Thanks for the video! Saved me from going hardtop. I prefer the soft top, easy access to drop the top!

[@one234569and10]

EXCELLENT video, thank you!

[@Lurchin]

Another informative video, thanks. Happy New Year mate

[@user-vj2nq1xm1h]

Great job thanks

[@FoxyFighter2000]

Great video

[@wrydhoe]

wow great video man!!! i was watching because i have to replace my tail light gasket but i’m so glad to learn about the sloshing around i heard in my car!!! if you wouldn’t have shared this i would’ve never known, thank you so so much!!!

[@iliyaas]

Thank you for the rocker panel explanation. I was wondering what the slosh was in my car.

[@SpaceShipDeathstar]

Thank you very much. Really helpful! Edit: I already did the taillights (changed stupid aftermarket crap ¡without! seals out for original taillights). Still had some occasional Water in the trunk. Today I checked my daily driver Miata and the passenger side was completely clogged. With the video and the method shown this was immensely helpful. Gonna check the other options (tank filler cup) next. Would have never crossed my mind that this could overflow back in the trunk.

[@adrianrowden8266]

Also a drain hole by the fuel filler cap.

[@SmooveBee1]

Very Very Important: Do all of what was mentioned already; Also: open your trunk, and just along the outside of the body-seal look at the paint-over-the-body-seam caulk ... that's right, that bit around the seal; is there a fine line of cracks that follows around? If yes, in an older NA or NB, this is dried-out cracked seam-filler that has contracted or shrunk a bit and the paint will reveal that because the paint cracks too; that is another common way for water to get into a car such as your Miata; you can seal that with some RTV Silicone; choose clear or in the case of black paint you can use permatex black adhesive/sealant; of course, the tail-light lens gaskets and all of that, but be sure to clean and visually check that channel around your body-trunk seal as well. It is more common leak than you might think and it is a small slow leak, so you may just have a 'damp' trunk vs a 'wet' trunk. These same leaks can occur anywhere body-caulk or seam-filler was used on your car.

[@SoundsOfTheTremors]

Another notable thing for those diagnosing, if you park on a steep enough incline with the rear lower than the front the water in the rain rail may not be able to make it's way up to the drain cups and it will overflow into the trunk.

[@MiataMan]

Very good point ✅👍

[@hillbillysportsman5818]

There is also a drain on the cowl area where the windshield and the hood come together.

[@bkawbtrs]

The cause of rust for fenders and the front rocker panels (;_;)

[@christianmagana329]

nice job showing exactly where and what's going on with the drain cup blockage. ended up pushing a bunch of crap out through mine. liked and subbed!

[@MiataMan]

Thanks Christian 🙏😃👍

[@nolahahnshouse3389]

Bro I've been trying to figure this out for some years now and still can't figure this shit out! I think I may have pin pointed it be still have to research something.

[@MiataMan]

Happy New Year 🥳 Please let us know how it goes. I have just added some possible leak zones to the video description.

[@abrameto]

How do you clean the cabin intake vent? It’s hard to get to, under the cowl.

[@MiataMan]

The best way is to remove the black plastic cowling that covers the intake vent.

[@kwl189]

It's not that hard honestly. Remove the wipers with a 10/12mm spanner. Take off the plastic covering underneath the wipers and that's more or less it. Be wary of the piping for the windscreen washers. There's also a rubber seal to look out for. After that, dead simple. Take the cowl out and replace them for new ones with new seals. Mine were ripped to shreds as it had been that long. Give everything a clean and wipe down with APC. Good tip is to put some bathroom clear sealant on the new cowl so that if and when it wears out or fails, it'll still stop the water coming down into the cabin. Also good to stop condensation. Both the driver and passenger side are worth doing.

[@Thompsongs]

3:30 I spy a yellow Protege5!! Please tell me that's also yours. I also have a yellow P5 and an NA Miata.

[@hillbillysportsman5818]

What’s that drain tube made of??? Rubber or plastic?

[@MiataMan]

The tray is plastic and the tube is rubber. There is usually a flap at the end of the tube that contributes to it being blocked by debris.