Peter T. has just changed his wiper blade inserts, thereby keeping the very nice Aero frames that are OEM with our car. He provided a nice collection of photos, which I am using for this article, since I have yet to replace my blades.
Description: Manufactured by Mitsuba; aerodynamic design so that wind pushes them down against the windshield at highway speeds; the wide rubber blade inserts are impregnated with graphite; the beam frames are made of plastic; although you can obtain replacement parts from FIAT , MAZDA part #s are shown, since re-branded FIAT parts are ≈ $100 for the pair.
♦ Left side: 18″ (450 mm) blade insert only – N247-67-333;
“Aero” wiper blade assembly – NA8W-67-330
♦ Right side: 19″ (475 mm) blade insert only – N256-67-333;
“Aero” wiper blade assembly – NA9C-67-330
(you can ignore any warning that the longer one does not fit your MX-5 Club or 124 Spider)
Mitsuba also manufactures blades for Honda, so if you wish to save even more money, Honda blade inserts can be used instead.
When installing refills, be sure to keep the metal stiffening strips (2 per blade; Mazda calls them backing plates) for re-use with the new rubber, with the indent (which keeps them from sliding out) facing out. Peter adds:
The rubber is seated in the frame by way of plastic bumps inside the rail that engage with the indents in the metal strips on both sides. All in all, there are about four bumps on each side. To get the rubber out you have to pull on it so the rubber slides past those bumps. You might even put some silicone oil or talcum powder around those bumps to reduce the sliding friction.
I noticed the drivers side blade rubber (450mm or 18″) did not have the corresponding notch whereas the longer passenger side (475mm/19″) did. Anyhow, I don’t think it makes a difference.
Install metal strips in new rubber by placing into slots on each side at one end and squeezing…
…run your fingers up both sides, straightening blade to help them snap into place at the other end.
Insert completed refill with metal strips back into wiper blade from the bottom end (toward the wiper arm). Now you’re done, and remember, the shorter blade goes on the left side.