70 Speedo Cable Routing
Thread Starter
Instructor
Joined: Feb 2006
Posts: 185
Likes: 2
From: Long Valley NJ
70 Speedo Cable Routing
Hoping somebody can help here. I am replacing the firewall holes with new grommets but I can't figure out where my speedo cable should route through the firewall. The AIM shows the cable routing thorugh the driver's side of the master cylinder...but there is no hole?? Currently my cable is routed through where the tachometer cable should go. The AIM has never been wrong before so what gives?
Thread Starter
Instructor
Joined: Feb 2006
Posts: 185
Likes: 2
From: Long Valley NJ
Instructor
Joined: Dec 2008
Posts: 180
Likes: 1
From: Charleston SC
Just a little grease and it will slide through the smaller end of the speedo cable. Just make sure the metal prongs face the firewall because that's what they clip on to. This grommet is kind of weird because all the rubber hangs in the engine compartment.
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
I just replaced the cable and sleeve on my '69 on saturday.
For the manual trans...
The cable leaves the passenger side of the transmission and goes a fwd a few inches to a hanger. Then it bends upward towards another hanger and once in position that hanger should keep it away from the exhaust manifold/header. I used a zip tie to connect the cable to the starter motor wires just below that hanger to make sure it stays well away from the hot tubes.
Then the cable takes a bend up and left to a hanger low on the firewall and before the distributor.
The next hanger is on the opposite side of the distributor at the same height as the last. Just route the cable underneath the rest of the wiring in this area.
After this last hanger I believe the wire takes a straight path to enter the firewall just aft of the brake booster (if you have one). It sort of enters the firewall at 90 degrees from how it will connect to the gauge.
Worked for me.
For the manual trans...
The cable leaves the passenger side of the transmission and goes a fwd a few inches to a hanger. Then it bends upward towards another hanger and once in position that hanger should keep it away from the exhaust manifold/header. I used a zip tie to connect the cable to the starter motor wires just below that hanger to make sure it stays well away from the hot tubes.
Then the cable takes a bend up and left to a hanger low on the firewall and before the distributor.
The next hanger is on the opposite side of the distributor at the same height as the last. Just route the cable underneath the rest of the wiring in this area.
After this last hanger I believe the wire takes a straight path to enter the firewall just aft of the brake booster (if you have one). It sort of enters the firewall at 90 degrees from how it will connect to the gauge.
Worked for me.
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
I just realized I explained EXACTLY what that picture shows. It does actually show the routing for the manual.
They should have shaded the portion of the cable from the grommet inward a different way to show that it is INSIDE the firewall.
The picture actually depicts the 90 degree bend which takes place inside the firewall on up to the gauge.
They should have shaded the portion of the cable from the grommet inward a different way to show that it is INSIDE the firewall.
The picture actually depicts the 90 degree bend which takes place inside the firewall on up to the gauge.
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