Transmission won't go into 2nd gear

[JFairman]

Out of the blue and with no symptoms that something might be wearing out or going wrong, my transmission just won't go into 2nd gear anymore.

It's a 1987 930 4 speed transaxle that was rebuilt about 20,000 miles ago by the previous owner. I have the receipts with all the parts that were replaced including the synchros.

It has a low grade short shifter that uses a weltmeister spacer plate to raise the whole shifter up around 1/2". That was in the car when I got it.
Seems some parts are missing from the shifter from diagrams I've seen online. There are no springs in it. Just the pivot for the shift lever.
It works OK so I hadn't decided to replace and upgrade it with a Wevo shifter or whatever ...yet.

I shift gears at regular speed, pausing a split second while the synchro unit does it's job on upshifts before moving the lever all the way into gear smoothly and I always match revs double clutching on downshifts.
The transmission was working perfectly with no grinding or noises, but maybe the shortshifter was still rushing the synchros or something.
It has a limited slip differential.

While driving, I tried pulling back into 2nd a little harder to try and get iit into gear and it felt like the synchro slider or operating sleeve was engaging with the synchro with difficulty and it locked in partially without fully engaging the 2nd gear selector teeth. It was locked there and wouldn't go into gear or back into nuetral so pushed harder towards nuetral and with an unpleasent sounding bonk it let go and went into nuetral.

I took apart the shifter and replaced the bushings, and repalced the 2 bushings in the rear shift coupler. They weren't worn much and having done that it still won't go into 2nd.

I guess the whole thing has to come out and be taken apart to figure out whats wrong.

Also, here's a list of the transmission parts that were replaced by the previous owner about 20,000 miles ago.
The top end of the motor was done at the same time so those parts are mixed into the list from the receipts.

Has anyone experienced anything like this, and does anybody have any ideas?

thanks in advance,
Jim

[Christien]

Will it go into second with the engine off? Try adjusting the shift coupler - if there was nothing noticeable that led to this, it's possible it's just come out of alignment. I would definitely spend an hour or so with that before going to all the effort of dropping the engine and tranny.

[JFairman]

Thanks for your reply...

It won't go into gear with the engine off either.
I tried adjusting the shift rod coupler after replacing all the bushings.
I thought it might be the coupler at first because it became hard to shift into 4th at the same time but with a little more push on the gearshift lever it went into 4th, and i could get it back into nuetral from 4th normally.

It's weird because the car shifted perfectly normal the last time I drove it and then the other day from a cold start it wouldn't go into 2nd the first time I tried.

I can still drive it using 1st, 3rd, and 4th, so I'm gong to do that tomorrow hopefully, and get the transmission oil warmed up and see if it will go into 2nd.
It's as if something in the internal linkage has gone wrong, or something in the 2nd gear synchro, but the fact that 4th also became hard to shift into at the same time makes me think it's the linkage because 2nd and 4th synchro units are completely seperate.

I rebuilt a BMW 2002 4 speed getrag gearbox with borg warner synchros many years ago so I'm familiar with how those 4 speeds work.
The porsche synchros are different and appear to have more parts than the borg warner brass synchros.

[Dixie]

Will it go into 2nd if you double-clutch it? Does it pop out of gear? Answering those questions will help define if it's a syncro, or a dog-tooth problem.

[JFairman]

It won't go into 2nd gear by spinning up the gear set by double clutching.

I havn't been able to get it into 2nd with the motor running or not, so I don't know if it will pop out of gear. It never did anything odd before driving it the other day.
I only went a few blocks and went back home and parked it.

My guess is something in the internal shift linkage or some part in the 2nd gear synchro unit has gone wrong, without any kind of symptom or noise in advance.

Only thing I havn't done is drive it for a while the way it is using only 1st, 3rd, and 4th gear to get the oil warmed up and then try shifting into 2nd to see if it will go.. maybe I shouldn't even do that because it may be causing more damage.

There were no weird symptoms at all before trying to drive it the other day when this happened the first time I tried to shift to 2nd.

[Christien]

With any luck the pros will chime in here, but it really doesn't sound like something in the tranny. If you can't get it fixed by playing with the adjustment, try draining the tranny oil and seeing if any metal bits come out. But if there was something serious enough preventing any 2nd gear engagement whatsoever, I would think you'd hear it or feel it through the shifter.

But if it won't go into 2nd when the engine is not running, everything still seems to me to point to an adjustment issue.

Just a thought, maybe a dumb one, but is it possible there's something in the shifter bottom (where the bushings are) preventing the lever from moving?