Trying to get the tach working on my 69 L-46

[Michael L.]

Guys,

Now that I have the ignition issues solved I'm trying to get the tach to work on my 69 L-46. I've disconnected the cable from the back of the tach and when I make sure the cable inside is properly pushed in, the cable spins when the car is running but when I connect it to the tach it still doesn't work. I've pushed like crazy on the cable to ensure it is fully seated in the tach and it appears to be as in as it can go and the cable does lock on the retainer on the back of the tach. What are some other things I can do to trouble shoot this?

Mike

[Mark E.]

Re: Trying to get the tach working on my 69 L-46

Congrats on making good progress on your car over the past few days!

Tach heads do fail but it's more common for the distributor cross gear assembly to stop working.

Check tach operation by disconnecting its cable from the distributor and spin the cable with a variable speed drill at a low speed. Make sure to spin it in the proper direction (I don't remember that off hand but you can bump the engine to check).

With a helper watching you should be able to see the needle move a bit even by spinning the cable by hand.

[Mike E.]

Re: Trying to get the tach working on my 69 L-46

Counter clockwise. Did you check the end of the cable? Sometimes it is worn just enough that instead of being square, it is rounded just enough to slip inside the receiver in the tach. That also can happen on the distributor end.

[Michael L.]

Re: Trying to get the tach working on my 69 L-46

Thanks Mark. I should have mentioned that neither the tach nor the speedo is working. Both were restored by a reputable place that advertises in the Driveline. For now although the tach cable is spinning the speedo is not when I put it in gear. I'll see if I can get the tach to work with the power drill you mentioned. I also ordered a spare tach off of ebay that the seller says works so I'll try that too.

Mike

[Michael L.]

Re: Trying to get the tach working on my 69 L-46

Thanks Mike. Is that counter clockwise as in have the drill run in reverse? Both cables for speedo and tach are brand new with zero time on them.

[Patrick B.]

Re: Trying to get the tach working on my 69 L-46

Thanks Mike. Is that counter clockwise as in have the drill run in reverse? Both cables for speedo and tach are brand new with zero time on them.

[Mike E.]

Re: Trying to get the tach working on my 69 L-46

Yes, have the drill in reverse.

[Michael L.]

Re: Trying to get the tach working on my 69 L-46

[Mike E.]

Re: Trying to get the tach working on my 69 L-46

The end that has a shoulder on it should be on the tachometer end.

[Mark E.]

Re: Trying to get the tach working on my 69 L-46

I had a new speedo cable for a C2 from Paragon and it was almost 1/2” too short to engage the plastic speedo gear in the transmission to drive the speedo. Were these Paragon cables?

I've heard of this problem with replacement cables before. We may be on to something.

[Michael L.]

[Michael L.]

[Patrick B.]

Re: Trying to get the tach working on my 69 L-46

Exactly the problem I had with a Paragon speedo cable for a C2.

[Mark E.]

Re: Trying to get the tach working on my 69 L-46

Where did you get the cable that worked?

[Michael L.]

Re: Trying to get the tach working on my 69 L-46

I got the replacement at Paragon as well, but it is a different length. The inner cable is the same, it seems the outer cable is the one that was made too long on the one that didn't work. the attached pic shows the difference in how far the inner drive has to project in order to work. If it doesn't you need a new cable. I looked into it and you could I think pry the clamped tach end of the cable off and remove 5/8" from the cable and then reattach the end if your in a bind and want a quick fix to finish a project.

Mike

speedo cable.jpg