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Discussion Starter · #1 ·
Anybody know how to wire a parts place hood tach? I bought one a year ago and never had a chance to install it and I realized it didnt have a wiring diagram. I plugged the red thing into the power part on the distributor and that didnt work. then i cut the red thing off and wired it directly to the tach section of my distributor (Small block chevy fyi) and it STILL didnt work. like when I turn on the car I know it has power, and it bounces to 8000 and back to 0 but when I rev the motor the tach stays at 0. any ideas?

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Sounds like you've got the 12v+ power hooked to the tach trigger lead that should go to the distributor
"tach" post(HEI) or the coil negative post(points).
Tach trigger is the negative side of the coil...NOT the positive.

Just looking at the harness magnified, looks like 12+ power is the fused line, the ring terminal is ground, and the red plug is the coil negative(HEI "Tach" terminal" hookup. Appears to be no separate "lights" hook-up.

There will be three or four wires to a tach wiring harness.
12v+ power for the tach meter
Ground for the meter
Tach trigger from coil negative post
Internal light wire.

The internal light may be either wired to plug into the lighting harness to come on with the driving lights/headlights, or it may be integral to the 12v+ power input wire and be on whenever the key is on therefore no external hookup for the tach light.
Or maybe there is no light in it, IDK.

Have you got the old style points ignition?? Or has the car been converted to a newer HEI distributor??

Call the company, they should be able to tell you what wire goes where if you can't figure a way..
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