Speedometer Bung on transmission.

[cygnusx1]

I have two versions of the speedo bung that gets pressed into the trans and held in place with a small screw and steel tab. I have an aluminum one and a steel one. Both of them have the speedo gear held in place with a tiny split-pin. The speedo gear is also eccentric to the body of the bungs.

 

The steel one is on the left the other two are aluminum.

(photo linked from http://www.geocities.com/zgarage2001/engine.html)

 

1)What is the proper procedure for installing these bungs?

2)Should the only part sticking out of the trans be the threads to screw on the speedo cable?

 

Mine is showing about 1/8" of shoulder in addition to the threaded portion so the little metal tab that holds the bung won't sit flat against the shoulder and seems to keep me from fully threading on the speedo cable.

 

BTW the reason I am messing with this is that the original aluminum one was leaking oil past the inner oil seal of the bung and the speedo cable and bottom of the trans were very oily. My steel one seems to have a better seal because it seems newer. I changed the outer o-ring, swapped pinions, and assembled it all but something doesn't seem right with the way it fits.

 

One bung comes from a 76 Z 4-speed and one is from an 83 200SX 5-speed which is the same as the ZX 5-speed housings.