11-14-2012, 05:20 PM
Join Date: Sep 2009
Location: Skokie, IL
Total Cats: 4
Miata won't go into REVERSE, even when off!
Recently, my brother's 91 NA with 204k on the clock has not been wanting to go into reverse. It worked all summer, but as the weather dropped it started to get worse and worse. I've done as much research as I could with respect to reverse gear issues but I haven't found one that specifically deals with my situation and provided a clear-cut solution. I have, however, been able to run a couple of points through my head that I'd like to go over with you guys as well.
First things first:
-91 NA, manual, 204k miles. Purchased recently, all fluids have not yet been changed except motor oil/filter and coolant.
-Temperature has been 30-40 degrees outside. Cold.
-Transmission will shift into every other gear, including 5th. Just not reverse.
-Clutch has not been adjusted, nor has the master/slave cylinders been bled.
-Cannot shift into reverse at all (on or off). Even after the car has been running for several minutes.
-Torn upper boot, intact lower boot. Bushing on the bottom of the shifter is still intact. Turret oil is green-looking and thick.
-I've tried shifting through all gears before putting it back in reverse. Still no luck.
-I've tried putting it back in neutral, releasing the clutch, re-engaging the clutch and shifting into reverse. Still no luck.
-It is not stuck in any gear, because I'm able to push the car.
Points I'm THINKING can be ruled out, based on what i've read:
-If it were a bad synchro, I wouldn't be able to go into 5th either. Transmission should be fine.
-Car won't go into reverse even when the car is off, this checks off the slave/master cylinder being bad or needing to get bled.
-The only thing that's broken on the shifter assembly is the upper shift boot. Since the lower shift boot is still fine, I'm assuming nothing could have dropped into the turret to physically block the reverse gate. Lower bushing is still fine as well.
-Haven't checked the reverse switch that i've read can become faulty, but I do know that when the car was able to get into reverse, the reverse lights did turn on.
I just purchased some AMSOIL trans and diff fluid today. I'll be replacing them tomorrow along with the shift turret fluid. I'm not too sure if that alone will make much of a difference though. Other than that, I think that's pretty much everything I know, if there are any other suggestions/advice/questions I would greatly appreciate it. Thanks guys!