915 trans (5 gear) stuck in reverse

[911freek]

Hi all, my car is stuck in reverse. The gearbox was rebuilt 3k miles ago, but I suspect an improperly adjusted shift coupling from the last service is the culprit.

I'm planning to try freeing it by removing the backup light switch and pushing the selector rod, as suggested here.

Quick questions before I start:

1. Wrench size for the backup light switch?
2. Disconnect rear coupler first? Yes/No?
3. Approx. diameter of the switch hole (for a push rod)?
4. Is it okay to gently tap the rod (soft hammer) or just push?
5. Depress clutch while doing this?
6. Transmission oil? Would any spill out and would I need to top it up?

Thanks for any advice!

[Nick Triesch]

Tow it back to the shop that did the rebuild.

[Henry Schmidt]

I would suspect a misplaced detent. Remove the shift fork locator cover and look inside.
I believe you will see that a shift shaft has moved without the shift lever in the slot. If so, reach inside with a small pry bar (or screw driver) and move the shift shaft back in place. This event can happen after a rebuild where the detent location is inadvertently ignored. It can/will happen again if you shift quickly either into or out a reverse.

[john walker's workshop]

Remove the backup light switch and force the pin inward to pop it out of reverse. Then have the shop fix the detent issue.

[blucille]

is it possible the spring loaded tang in the shift column has locked the shifter in reverse? You say the last thing that happened was the shift coupler. I'd start there.

[CarlPet]

Had the same issue though through wear and tear, a gearbox overhaul fixed it.
22mm spanner, I was able to push the pin in with my finger and it took the car out of reverse, was then back to normal operation. Complete stop and slow, deliberate gearstick movements into and out of reverse.
A tiny amount of oil dripped out but only a tiny amount.

[911freek]

Update: I've resolved the issue, thanks for your input! Interestingly, I was in 1st gear, not Reverse, when this occurred, making it quite unusual. The problem was a stripped screw on the rear coupler (Part # 90007503203) where it connects to the rod. It seems the threads gave way, probably after the last adjustment, causing the rod to behave erratically despite appearing secured. And yes, I'm finding the 915 gearbox to be less than impressive in terms of design and German engineering.