Tranny leaks

[Zed Head]

Sometimes the end of the cable will not seat in the speedo drive, even though the housing screws all the way down.  Best practice seems to be to pull the cable out of the sleeve and seat it firmly in its spot in the drive housing then push the cable back in to the sleeve while screwing down the locking ring.  If the car is up in the air it helps to spin the drive/propeller shaft with your hand while tightening down the locking ring, to get the slotted end in its spot in the speedo.  You might have to try that a few times until both ends of the cable get seated properly.  Not uncommon.

 

[73avocado]

So, in comparing the old and new housings, it looks like the offset in the shaft hole faces the opposite direction. In the pic, the locking shoulder in both is facing the same way. You can see the gear in the new housing over hangs to the right, but the hole in the old one is closer to the left. I’m going to see if I can put a shoulder on the opposite side of the new housing. 

[Zed Head]

You can swap the gear and shaft over easily.  Push out the small roll pin and the gear/shaft will side right out.  It takes some finagling to get the pin out and in but it's not too hard.

[EuroDat]

Thatis because you have the later version. The version for the F4W71B and 280Z F5W71B is not what you see on most of the websites. I don't think it is still available. The later version 280ZX F5W71B and the F5W71C that had the non electronic speedo have the locating bolt under the speedo adatpor. You bought an adapter for those transmisions.

All the seals and pinion will fit your adapter, but I don't like your chances of getting the inner seal out without damaging it.

It is a simple fix. The groove for the locating tab and M6 bolt is on the wrong side so you can make a new groove or send it to a machine shop to make one.

You can make a groove yourself by carefully cutting a groove with a hacksaw and fine tuning it will a small metal working file. Buy a file that fits easilly in the original groove. Remove the outer o-ring seal and tape over the ends to prevent shaving entering the adapter. Don't go too deep or it will allow the adaper to turn and the gears will loose contact. You can test if it is deep enough by fitting it to the transmission (without o-ring or pinion gear) then fit the tab and bolt. Take little steps at a time. Too far and it is ruined.

Tip: To check that you are exactly opposite to the original groove. Use two too straight edges like a ruler or back of a hacksaw blade. Place one in each groove so they extend out the same direction. If they are parallel to each other, then your new groove is exactly opposite.

I wouldn't use your original adapter without replacing the inner seal.

[73avocado]

Good call EuroDat. I ended up cutting a slot in the agreeably soft aluminum of the new housing. Upon installing, I found that it went in past the slot anyway. I thought maybe I had installed it too far in, but it works fine, so I left it. Speedo works, no more leaks!