Transmission leak-speedometer port

[JohnnyJ]

79 Corvette. I have a leak where the speedometer cable goes into the extension housing of the transmission. is there an "O" Ring there, and how do I get to it??

 

[Bob Chadwick]

Take a look at this post. It has the AIM diagram for this part on a 77.

http://www.corvetteactioncenter.com/forums/showthread.php?s=&threadid=15869

The o-rings go bad and the whole thing is like $10 at a speedo shop. This is the whole piece not just the o-ring.

Bob

 

[1yy07]

Dont forget about the little seal on the gear that goes to main shaft.

 

[Bob Chadwick]

I think the stainless steel insert covers all that. As I recall, when mine started leaking I got a stainless steel insert that had two O-rings on it. This insert went inside the transmission and sealed it when the piece that screwed into the trans was seated. The speedo cable then attached to this piece.

 

[Pepe Le Pew]

I also had a leaker when I bought my 80, the same place as you discribed. My cable just unscrewed from the transmission and I replaced the O rings inside and it was good to go. It was easy. The only problem I had was unscrewing the cable. There was not much room for my hands. I had to push the transmission up a little with a small hydraulic jack to gain an inch or two. Enjoy! :s

 

[JohnnyJ]

Speedometer / leak at transmission

Thanks to all for your help. I tried calling many shops and car part shops for the part..no help. Ended up buying modified cable adapter from Chevy for $19.00. Looksnlike a good fix.