C2 tach movement

[Wayne K.]

I noticed lately the tach sweep has not been consistant on my 67 L79. In 1st gear and somewhat in 2nd when accelerating hard from between 2500 and 3000 going to redline the needle stalls ( doesn't continue at the pace of the engine ) in the area of 4000 to 4500 and then suddenly shoots up to around 5500 like its catching up to the engine. It has been approximately 7 years and 14000 miles since the distributor was out of the car and checked over and cable greased. The distributor does not have the button. The cluster was gone through before I bought the car and I have no history as to what was done mechanically to the tach. Is it just time to grease the cable or is something else suspect.

Wayne

[Jack H.]

Re: C2 tach movement

Lube the cable (can't hurt) and be sure to visually inspect the drive end...should be nice and square and make a firm fit into the distributor's drive keyway! If corners show 'rounding', the cable could be slipping under stress and it may be time to replace the inner cable with a speedo repair kit component.

[Bob R.]

Re: C2 tach movement

Jack,
Reading your comments on the cable caught my attention. My tach needle was bouncing and soon after the cable broke. I replaced the cable with a repo. It's not the same legnth as the original and the outer covering is not the same color. Does some vendor sell a replacement for the inner cable. I saved the old cable if I could get a replacement I would like to reinstall the original.

[William C.]

Re: C2 tach movement

Your local parts store (NAPA or whatever) can sell you a kit (speedometer cable repair kit) to replace the cable inside the sheath. Cut to length, add proper end fitting (supplied with kit) and you are done with the cable fix, then hope that was the source of the problem.

[Wayne K.]

Thanks Jack, I will check/grease cable first. *NM*

[Bill Jennings]

Re: C2 tach movement

Jack;

At the risk of sounding ignorant, how do you lubricate the tach cable? I have a similar issue on my '65 and I'd like to lube the cable as well. What type of lubricate do you recommend and how should it be applied?

Thanks,

Bill