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Can someone with more experience with transmissions give me some idea of what happened here? Just before I came to a signal I heard a funny snapping noise and the speedometer stopped working. Speedometer cable has been broken before so I knew what to do. Car still drove in all gears the short distance back to my garage. When I looked underneath the car I discovered the end of a gear shaft through the back of the transmission case. It was like something was shot through the back of the case. There was a 3/4 inch hole in the case with vital fluids leaking out.

Not sure what my next move is but I found another working transmission that I can pick up later today. Before this happened the trans in my car was one of the smoothest working gearboxes I have experienced in a 914. At least in the cars I have owned and the others I have been in. Is the problem isolated to a speedometer gearing thing or is was this the death cry of this transmission and I have to junk it. I have time this weekend so I hope between two transmissions I can get one good one.

Any words are appreciated.

Saw this exact thing happen to a car about two months ago, and his was the first I ever encountered. You can pull the nose cone off the tranni without pulling the tranni. Could be an easy fix. Keep the fingers crossed.

the large nut with the brass speedo drive came loose and did a nice exit looks like. Should be an easy fix if thts all it was.

Perhaps just this nut...

Thanks for the quick replies!

Anyone have an idea what size metric tools I need to have in hand to do this? That nut looks quite large. Do we think this is the case getting old? Other problems contributed to this? What if I remove the part, replace the case and leave the speedometer not working? Other than a dead speedometer what else would this interfere with?

You are lucky it didnt go worse. The bolt (not nut) that has the speedo drive in it has worked its way through the back of your tail cone. This is one way that this can go, the other is to have your pinion shaft go forward and destroy your gear box (ask Jakeodule).

You will need to get a new tail cone (I have for cheap if you do not have), and you will need to pull the stack and clean out all of the metal parts in there. If you do not clean out the gear box you will wear out your shafts and gears and your tranz will quickly wear out. I would recommend resealing the whole transmission.

If I can help, let me know.

That bolt is 30mm and needs to be torqued to 80ft/lb. You need to do this correctly or you will break teeth off of the gears and damage intermediate plate bearings. To correctly tighten the bolt, you need the alignment jig to hold the shafts together. You will have to pull the stack either way. I would be happy to inspect the stack for you and to tighten the bolt (install a new one $15) for free to make sure it is done right.

Why this happens is due to several reasons, most of which have to do with improper installation of the bolt.

DrEvil,

Is the stack the assembly that is in the image that McMark sent to this posting? I feel like I will be removing the entire transmission to remove the stack. Is this correct or will it pull out of the rear with the trans on the car?

Yes, that is the stack. You would do better to remove the transmission since I would recommend resealing the case and this needs the transmission out to be done.

There are links in my rebuild thread (link below under Rebuild Transmission) that may help you make a decision on how to proceed. There are a few links to rebuilding that show how to pull things apart.

Bill, you are also welcome to call me if things get a bit to overwhelming and you need some detailed options that would give me a hand cramp to type

I'll check back in a few. I need to start two papers.......yay

Mike,

Since I am motivated to get this car together for a fun run at the end of this month I have come up with this plan.

I am thinking that I pick up and install the trans I found on this board yesterday to keep the car running. I already know that the temporary trans will have the typical first gear syncro issues common to most.

Will remove my old trans, remove the stack and send it over to you for rebuild as soon as I can. Once returned I will of course, have to remove the trans again and replace with the new bits.

At the end of the day, other than the extra amount of work of transmission install I should be back to running in fine order with a reliable trans.

Flogging a used box is fine Its always good to have 2.