Vet65te

Just pulled the instrument cluster on my 66 L72 Roadster and have a freshly rebuilt Speedo and Tach from Joe Ray to install...along with a replacement Amp Gauge.
The tach was inop when I got the car but when I happened to pull the distributor for a freshen up, I found the side gear to be in good shape but the tach cable inside the sheath (at the dist end) had
a buildup of cable-strands around it. Once I got the old gauges apart, I just used my fingers and saw the tach moved so the cable was at fault.
Since most vendors are having issues getting parts in due to the supply issues with that particular part on long backorder, I figured I'd use one of the replacement speedo cables I have (both aftermarket and GM) and cut it to fit the tach cable housing.
It's the generic type where you cut to suit and crimp on the square fitting.
Problem is, I can't extract the cable itself short of cutting it out and while that might work, I was hoping that someone might have a replacement cable/housing available so they can tell me the exact length dimension.
Thanks,
Mike T - Prescott AZ

apahl

Hey, Mike, I just put my 65 back together and my old tach cable measures 23.5 in from the ends of the nuts when they are all the way at the ends of the cable housing . The cable itself is about 1/2 to 5/8 longer than that on each end.

Vet65te

Anrdrew - After I posted the thread, I pushed/pulled/pried and finally got the old tach cable out of the 'clutches' of the firewall grommet and realized something was off. I thought the tach cable in the car was the original but turns out it's not, it's a helluva lot longer than it should be. Once on the bench, I pulled a bit harder on the gauge end and it did finally let go but at the other end I found that buildup of spiral wound wires meant the cable had parted ways a long time ago, hence the reason for no tach action. Pics attached.



Measured the overall length and found the reason why the lower end looked like it was coming out of another firewall penetration, this one was around 32 inches long and should have been around 23+ inches. Wrong length I can live with to a point as long as it functions correctly but the old housing is nearly 'petrified' and my attempts to carefully straighten it out met with 'cracking' sounds so I went back to my original vendor and found the order sent in late August was still open because no parts availability, checked another large and well-known Corvette Parts Vendor and same thing but did find one vendor that had the stock replacement tach cables on the shelf and it's been ordered and will be here in about 5 days.
So, now it's time for me to get busy on the cluster freshen up and steering column...and since Gary Ramadei's package of steering box rebuild parts has arrived, time to put that back together too.
Thanks for the help.
Mike T - Prescott AZ