Hello,
I'm in a bit of a pickle. I was test driving my '74 2.0 before a track day, and hit a bump in the road. I immediately lost shifting power, and can no longer get into gear. I have a Rennshift shifter in the car, and the car has the side shift trans. I checked under the car after towing it home, and wasn't able to find any visible damage. The clutch engages and the cable is in fine condition. There is no visible damage to the shifter rod, so my question is this: what would be the first failure point in an event like this? Could the Rennshift have been taken out of adjustment by the bump? Could I have shattered the plastic bushings? My fingers are crossed that I didn't ruin the transmission, but since this is a low car I'm hoping that someone on this forum has gone through something similar before. I'm slowly learning how to work on cars, but this issue has left me totally stumped.

Check the front and rear coupler screws.

Do you have any gears at all?
Bushings are a good place to start but you may still be able to get a few gears.
Did you check all of the linkage bolts to see if any came loose or fell out?
Have a helper shift the car for you as you look under to see if all the linkage moves.
Also check the trans shifter console roll pins. There's 2 of them, one that holds the ball stud and another internal for the shift fork selector. Pretty straight forward linkage setup so if it's all intact start looking at trans internal.

I have no gears, I can put the clutch in and try to shift were the gate would normally be, but I hear grinding (Which is weird as the clutch seems to work). In my understanding if the clutch was fully functioning the gears wouldn't me moving so there wouldn't be any way for it to grind. I'll check those bolts/pins, my dad and I are going to be spending the next few hours looking at this.

One of the cone set screws came lose, probably the one on the first coupler right after the firewall.

Get under the car and check the coupler. If you still have the rubber boot that goes over the coupler the screw might be lying in there.

Don't reuse those setscrews (unless you are in a pinch to get home) they have special threads that deform when tightened to make them lock. Replacements are cheap.

Jwest coupler screws are reusable.

Okay, after looking at where the shift rod enters the trans I'm not sure if anything broke. I had my dad shift while I was under the car, and surprisingly he was able to grab 3 gears. The coupler into the transmission was working fine, and the rod was moving while he shifted. Could the bump have knocked the rennshift out of alignment? Thank you guys for all of your help already, all of this has been super helpful. We checked the coupler screws, and they seemed to be in fine condition.

But did you check the coupler at the firewall?

You say the clutch engages? Sounds like clutch tube possible let go inside the tunnel? Which doesn't let it engage fully & why it could be grinding rather than going into gear

My shift coupler at the firewall went from rubber to glass and disintegrated when I hit a bump on the track. As the pieces fell out, I could engage less and less gears. It hides under the boot. See if it is still in one piece.

I'll check in a minute, ill also take a look at the clutch cable in the tunnel to make sure it fully engages correctly. Thank you for the helpful advice!

X2.

I use blue LockTite on my setscrews.

Years ago, pre-internet, pre-914-world advice, I had the same experience when the original equipment bushings in the forward shift coupling disintegrated. Gear selection disappeared. I found the pieces in the rubber bellows boot. I replaced the coupler bushings, along with the fire wall and shift console bushings and shift rod cup bushing. The resultant shifting felt like new.

The shift rod is made of two components connected together. I once experienced a disconnect where the rear part of the shift rod was freely pivoting inside the thicker part. I was only able to get into fourth gear, and with some difficulty.

Repair was to reweld the two parts together and drill and insert a pin to ensure it doesn't come apart again.

I have a video somewhere showing this up close.

I’ve checked the firewall boot, and everything is in good working order. The set screws have not backed out, the firewall coupler seems in fine condition :/ . This one’s leaving me kinda stumped

I've bent the 4cyl engine mount by bottoming out, which threw my shifting out whack. Might be worth checking.

It seems to me that even if the shifter were completely out of adjustment the gears shouldn’t grind if the clutch is working correctly. I would make sure the clutch fork has full travel where it goes into the bell housing.

Jeff B

Did you actually check the set screws?
I have the same set up and rennshifter plus I had the exact same issue. BTDT
I can't remember which one but it was a set screw.

You can have someone try to shift while you watch. If the movement from the firewall is not the same at the trans you have a screw problem. If not you need to start looking at the trans side.

I suspect it's in the shift rod section as it's the weakest link - sorry bad pun