Tach Problem--1961 Notchback Restoration—Solution Found

[Lynn Sheeley]

1961 Notchback Coupe. Tach fresh rebuild by North Hollywood. New Stoddard tach cable and new seal in tach drive
at oil pump. Forgot to order the shim but read a thread that most were missing shim and tach would still run.
Metal end of cable hooked up at tach drive, rubber covered end under the dash.

With cable hooked up at engine drive the cable insert spins with cable loose on the instrument end. Pretty sure everything is
installed correctly. Was careful to keep cable square to the end of both connections.

Tach does not spin at any engine speed.

Should I hook up under the dash first and then at tach drive or does it matter?

The thread with the cable not working never showed a positive outcome.

[Mike Wilson]

I'd try inserting the cable into the tach first but also checking the length of the cable.

Mike

[Dick Weiss]

Lynn,

Did you just replace the tach cable insert, or the whole unit with it's sheath/cover?
When inserting only the insert, it must be installed from the front end due to it's tiny 'captured' bushing on the end of the cable.
In any case, make sure both ring nuts are fully connected after the cable ends are inserted into the drive & driven shafts.

Dick

[Jim Liberty]

You can test the tach with an electric drill. Be sure it is turning the correct direction.

[Harold Singh]

You can test the tach with an electric drill. Be sure it is turning the correct direction.

Good tip.


Which way is the correct direction? Clockwise, righty tighty, or lefty loosey, counter clockwise?

[David Jones]

Whichever way makes the tach read. If it don't read either way it is broke.

[Lynn Sheeley]

New cable and insert and plastic spaced on insert is on gauge end. Both ring nuts are snug.

Not going to drill test a $600 fresh rebuild without knowing which direction to set drill.

With the cable connected to the drive end and turning with engine running and plenty of insert end sticking out on gauge end to connect to gauge drive and cable installed don’t think measuring the cable is needed.

[Jim Liberty]

Lynn, watch the direction of the cable end at the tach, when the engine is running. Set your drill the same. Thar way you can see if the problem is with the tach.

[John Hearn]

You have to rotate in the direction the tach needle moves.
That is clockwise from the front which translates to anti-clockwise from the back of the tachometer.
It really is that simple..............
KTF
John

[Jules Dielen]

insert cable in the drive at the engine side, but leave it out of the tach gauge. start your engine and look if the insert turns at the gauge end under your dash. if the insert turns, it's the gauge that is stuck.

[Jules Dielen]

how long ago was the gauge restored?

[Lynn Sheeley]

Did some more reading last night and found a thread if something is missing from the tach mount and you tighten the mount nuts too tight you can lock a plate inside the tach and it won’t spin.

I loosened my mount nuts from very tight to just finger tight and now the tach works as it should!

Can’t refind the thread. Does anybody know what is missing from back of tach to cause lockup?

[Jim Liberty]

that one is new to me.