CW or CCW

[Robert S.]

The tachometer stopped working this AM on my 74'. To troubleshoot I plan to remove the cable from the distributor and drive the cable end slowly with an electric drill to check the integrity of the cable and the instrument head.
Question: Do I drive the cable end CW or CCW?
I do not want to damage anything by driving the system in the wrong direction.

[Alan S.]

Re: CW or CCW

Hi Robert,
The cable turns counter clockwise. Because of the relatively low rpm of a hand drill you need to have it going almost full speed to get much movement from the tach needle.
There have been some posts about what lubricant to use in the cable, since you don't want it to work it's way up into the tach head. Perhaps you might want to check them out.
Regards,
Alan

[Martin N.]

Re: CW or CCW

ROBERT-

Another way to "hunt" down the problem is to remove the cable at the dist. and start the car and watch to see if your output (cable) gear is spinning. If it is next inspect the cable end and try turning the tach cable with your finger tips to feel if there is any binding or tough spots. At this point you're left with a bad cable or end at the tach or a tach that needs servicing. My 74 ended up just needing a cable.

Marty

[Christopher K.]

Re: CW or CCW

Robert,

When mine stopped on my '73 it ended up being a broken adapter, the one that mounts at the transmission. It's a sealed unit, and even the speedo shops can't fix them, but they can build a new functional unit. I found an original, working adapter after a lot of searching.

Let me know if this turns out to be the problem,
Chris

[Robert S.]

Re: CW or CCW

I ran the check tonight with the drill attached to the cable end and the drill run ccw. Looks like the problem is in the distributor which is not unexpected. Footnote: The drill did not need to run very fast to move the tachometer needle. Thanks to all for the replies. Another winter project to pull and rebuild the distributor which is a shame as distributor performance is flawless otherwise.