915 popping out of first gear - is a rebuild inevitable

[83911sc]

Hello -

I have an 83 911 and a running into a significant problem with 1st gear over the last 3 days. Although I am able to engage the gear, as soon as I let out the clutch and give some gas, the selector spits out of position and I am going nowhere fast. The first couple of days I could re-engage and I was a 70/30 likelihood of being able to go... now there is not a chance - I had to limp her home using second to take off....

I had a problem with this last summer and was able to "fix it" by replacing the the cup bushing, tunnel bushing and shift coupler (using the wevo). I also changed the motor mounts (although not the tranny mounts). All was good until this week.

I checked the coupler alignment and it looks correct - I had used a red sharpie as a reference point for alignment when I installed the wevo coupler. Even though all looked good, I played with alignment, tried resetting forward a bit and back a bit - not luck. Ultimately, I put it in the prior position. As a point of reference, third gear engages perfectly and does not spit out.

So, am I am missing something here, or is it looking like a 1st gear re-build (and 2nd - while I'm in there)?

Thanks in advance -

Adam

[SP2]

I am not an expert but I rebuilt my transmission last year. It sounds more like a coupler problem. I wouldn't go by the sharpie mark, especially if the coupler is not stock. It assumes the old coupler was set correctly and it might have been a little off then. I would look up the protocol on adjusting the coupler from scratch. I think John Walker has posted it several times.

I would think that if there was a problem with 1st gear itself, like the slider or the syncro ring or dogteeth, it would have a problem engaging, not disengaging. It didn't sound like you have any grinding problems. I'll be interested to hear what the others say. Good luck!

[83911sc]

thanks for the thought on the marking - however, I used the "Walker" system to do the alignment and the red sharpie was done after I got it just right.

NO grind at all, just a spit out and thunking sound.

[john walker's workshop]

teeth missing on the toothed syncro hub that holds the syncro, probably. see if you find them on the drainplug magnet.