mx5cartalk.com

Doing a bit of maintenance on my recently purchased NB8B
It had been serviced by Mazda dealers exclusively until I bought it.

It started when I fitted some front mudflaps.
Pulled away the rear part of the front innerguards, I found the guards packed with leaves and gunk.
Used an air compressor, I pushed some air through the drains from the front windscreen and in and around the guards.
Remove a pile of crap from both sides.

This got me thinking about the soft top drain holes.
If you have never cleaned these before, I recommend you grab a vacuum cleaner before you start pump air down these holes.
Give them a good blow with the vacuum nozzle close by to catch any blowback.

Also recommend you do it before you clean your car as it can (did) make quite a mess.

There is an article on the Miata forum on finding and cleaning the soft top drain holes using a long brush if you don't have access to a air compressor.
http://forum.miata.net/vb/showthread.ph ... ight=drain

If you use a brush, check the rubber check valve is correctly positioned once you have cleaned the drains.
http://forum.miata.net/vb/showthread.php?t=178793

If you don't do it, Mazda wont.

This is on my short list of 'must do's'. I think the driver side soft top drain is partially blocked. The car received a thorough wash yesterday and a few hours later there was still a very slow drip from the bottom of the drain.

Be careful with the drain holes. The actual drain hose is a separate piece and can come apart if you push it too hard or blow too much compressed air into it when it's blocked. It's easy enough to put back together ... once you remove most of the trim.

Thanks for the tip. This could explain some leakage issues I've been having recently.

NMX516 wrote:This is on my short list of 'must do's'. I think the driver side soft top drain is partially blocked. The car received a thorough wash yesterday and a few hours later there was still a very slow drip from the bottom of the drain.

Dodgy day?

There is a easy fix on Miata.net if the tube has come off.
Something about feeding a string or similar through, tying something on the end then gently pulling the tube back up.
http://forum.miata.net/vb/printthread.php?t=261405
Haven't had the problem, so I haven't tried the fix.

Another pair of drain holes to check/clean is the 2 on either side of the windscreen which run down the door rubbers.

I cleaned my drain tubes out the other day while I had the soft top off. Had gunk in them even though i had flushed them out with air last year. The gunk was sitting above the valve flap in the tube and there was also a bend in the tube. What is the flap for and has anyone taken it out to stop it blocking up? Also how do you stop the tube from bending and restricting the bore? Ta

trader wrote:What is the flap for and has anyone taken it out to stop it blocking up?

It's to stop crud from getting into the drain tube from underneath the car.

According to the Miata Forum, the flap is to stop road noise from coming up the tube.
Those who claim to have removed them have quickly found a way to replace them again.
http://forum.miata.net/vb/showthread.php?t=255042

I haven't had the bent tube problem (yet) so I cant comment.

How frequently you need to clean the drains would depend on how exposed to dust and leaves your MX5 is.
I'm thinking at least every 12 months when I clean out front guards on all my cars.
(like a dodgy day but for my own cars)

Thanks for that de bounce. My car is usuallly under cover but I suppose over the 17 years it has collected rubbish.

there are only 4 drains yeah? (NB8A)

one behind each seat on the shelf area.

where are the windscreen drains? I had a look and didnt really find anything, but then again, I dont know what I'm looking for.


I'm giving the car it's first proper clean and want to do the drains before I start.

Could someone please post some photos/instructions on how to access the drain holes on a NA6? I went looking for them but struggled to find anything that remotely resembled the above photos! Yeh, I know ... I'm a gumby!

hks_kensei
There are a pair of drains on either side at the top of the windscreen that drain the channel between the soft top and the windscreen header.
The drain is formed in the door rubber. Starts at the top of the windscreen and finishes below the door hinges on the sill.
Mine had a small amount of crap when I pushed some air through it.
See attached photo.

Guran
Don't have a NA6
I did find these photo's on the MX5 Owners Club site
They are not NB or NC so I'm guessing it's a NA
Middle photo just shows the left hand top seat belt mount in the top of the photo.

Hope this helps

ah, that's why I didnt see the windscreen ones, I was looking for specific pipes etc.

cool, looks like I'll be cleaning some drains this saturday mornign!

Guran

I've found best accessing the NA's drain holes is have the softtop up. The drain holes are right behind the seatbelt. So easiest way, pour some water and trace it back Its getting dark outside and I just cleaned a kg of dirt out of the front fender so i can't take some pics. But if you still can't find it, Ill try and take some pics tomorrow.