I have a 1972 Buick GS that did not have a tachometer in the Dash in stead it had a clock that did not work. During a swap meet, I came across an original 1970 Buick GS dash tachometer. I've attached 2 pictures that shows the front and back of the tachometer. Please let me know if anyone has any suggestions or supporting documentation on how to properly hook it up. Also, is there a way to test the tachometer to ensure it works correctly before I take the dashboard apart to install it.I have a regular stock distributor in the car, since the HEI are a little too much money for me at this time. Any assistance would be greatly appreciated it. Happy 2014 everyone.
The back of that tach does not look stock to me. It may be a reproduction. In any case, you can hook it to the - side of the coil to test it. The case should be grounded. Looks like you have 2 tabs there. Use a wire to go from one to the - side of the coil, and ground the other tab.
That is an aftermarket tach. Most aftermarket tachs require a 12 volt power wire in addition to the coil and ground wire. Unfortunately I don't know which terminal to tell you is for 12 volts, coil wire, or ground wire.
Just an FYI... The other clue to it not being a factory tach is the shape of the needle. Factory tachs have a needle of a constant width, then a point, like the speedo needle. Reproduction ones are one long continuous taper, as in the pic :Smarty:
The 70 I just got from a board member only has two terminals. One has a spade connector the other does not. I can't see in wiring diagram which is which.... to coil & to ground
The one with the terminal...that goes to the coil. There is no ground, it grounds through a small strap that goes to the speedo. It's like the strap that goes from the gauges to the speedo, but longer. You can make one from a small piece of wire with 2 eyelets, or you could make a strap.
Not trying to hijack this thread.... Do you know if it will it work fine just from the tach lead from MSD 6AL or needs a tach adapter?
The stock tach brown wire that is usually attached to the coil will work fine if plugged directly into the tach output on the MSD. That is at least on the old style MSD. I used it this way for years no adapter required.
I have an original 1970 tachometer, and running HEI ignition. I ran wire off tach output on distributor cap, and then grounded the tachometer body but I don't get a signal. Any ideas? I have a feeling that I bought something that doesnt' work.
That's definatley a reproduction tach. The case is textured plastic as opposed to metal like the factory tach
My tach is a stock GM tach, not the one pictured at the top of this page. Any thoughts on why it doesn't work with HEI. I have verified that it is connected to the tach lead in the distributor cap.
I know this is a old thread, but rather than start a new thread figured I would use it as it has pics..I need to find the L spade male connectors as on the rear of these tachs? I have checked a few parts houses and Ace hardware with no luck..If anyone can point me in the right direction it will be truly appreciated:TU:
They use them on the MSD cylindrical coils. They bolt to the terminals, and the female connectors slip over them. I don't think they sell them separately, but they are common in the MSD box kits. There are other ways to make that connection.
