Mazda North America reports that owners of 2007-12 Miata models with retractable hardtops may complain of a rattle from the roof panel while driving on the open road. One likely cause for the noise, the Japanese car maker said, is insufficient latching force between the roof's top lock and striker.
Furthermore, the condition gets worse as the rubber gasket deteriorates. Readjusting the lock's adjustment nut so that it provides less clearance between the roof panel and windshield header is the simple fix.
Begin the job by removing the top lock's spring from the retaining pin. Now remove the snap ring, followed by the retaining pin itself. Remove the lock cover's two screws, then the cover. Using the illustration above, turn the top lock's adjustment nut one complete turn clockwise to increase the latching force.
Continue the repair by reinstalling the lock cover. Coat the screw threads with an adhesive like Loctite, then install the two retaining screws to secure the cover. Insert the retaining pin into the lock, then secure it in place with the snap ring.
When properly installed, there shouldn't be any play between the snap ring and pin. To complete the repair, reinstall the spring onto the retaining pin, lock the roof panel, then make sure that the clearance between the roof and windshield header is 0.16 to 0.312 inch.
"Factory Fixes" is written by Jim DePalma, a 30-year veteran of the auto repair business who has served stints as a service manager, parts manager and ASE-certified technician. His column provides vehicle manufacturers' authentic factory technical service bulletins (TSBs) that have been condensed for easier reading. Mr. DePalma advises that techs always check with a dealer or repair information system for the latest revisions before starting to work on a vehicle. He can be reached via e-mail at [email protected].