|
|
|
|
| Author |
|
|
Registered
Join Date: Jul 2015
Location: Montreal, QC, Canada
Posts: 62
|
915 transmission with mecanical speedo cable
My 915 transmission receives the cable at the rear nose and not through a side mounted drive.
The speedo cable comes out of the rear firewall to the rear nose of the transmission.The place where it should connect has a hole near the top of the rear cover but there are no threads within this part of the transmission to accept the female threads included with the cable. Neither are there threads inside the hole to accept a male thread on some kind of adapter between the transmission and the cable. Past threads discussed the issue of removing this adapter with male threads that were difficult to remove from the magnesium transmission. The conclusion was that this adapter corroded with the magnesium and was very difficult to remove. In my case the hole is very clean without any marks that something was removed. What part (adapter) goes into the hole in the transmission and comes out with male threads to accept the cable? |
||
11-15-2022, 01:57 PM
|
|
|
Registered
Join Date: Jul 2015
Location: Montreal, QC, Canada
Posts: 62
|
I attached a picture of that part of the transmission. The hole is to the left and slightly lower than the reverse switch.
|
||
|
11-15-2022, 02:28 PM
|
|
|
Registered
Join Date: May 2004
Location: Boulder, Colorado
Posts: 7,275
|
What year car, engine, and transmission do you have, or think you have? It is best, when seeking help, to give those details along with the issue.
The 915 with a mechanical speedometer came on the '72-76 models. On those that boss you point to was threaded externally after the housing was cast. As is typical, when Porsche moved to an electronic speedometer, it didn't change the casting. So your transmission does not have provision for a mechanical speedometer. So either it is a 1977-1983 transmission, or someone changed the nose section of an earlier transmission (which is unlikely). If you look at the right side of the differential , forward of the axle, you should see a round hole about 2" or so wide, but with a solid bottom. The sender for the electronic transmission goes into that hole, and is held in place by a bent wire which is riveted to the transmission case and rotated into place. You don't show in your pictures the end of the cable for the mechanical speedometer cable, with its flat end and screw cap. Are those there? One thing which seems out of place in the photo is what looks like the ball cap end of the throttle linkage, which belongs on the other (left) side of the transmission. Is this just a trial installation? |
||
|
11-15-2022, 03:19 PM
|
|
|
Registered
Join Date: Jul 2015
Location: Montreal, QC, Canada
Posts: 62
|
The vehicle is a 1967 912 in which I installed a 2.7 engine with a 915 transmission.
My only conclusion is that the original 905 transmission was able to accept the cable through the front nose while the 915 transmission cannot. The solution would be to install a new electronic speedo with a sensor on the transmission. |
||
|
11-15-2022, 03:41 PM
|
|
|
Registered
Join Date: Jan 2011
Location: Gulf Coast FL
Posts: 1,501
|
Mechanical speedo trans are -75, yours is later
|
||
|
11-15-2022, 04:34 PM
|
|
|
gearhead
Join Date: Nov 2007
Location: Loverland, CO
Posts: 23,649
|
Quote:
__________________
1974 914 Bumble Bee 2009 Outback XT 2008 Cayman S shop test Mule 1996 WRX V-limited 450/1000 |
||
|
11-16-2022, 06:00 AM
|
|
|
