Trojan Boat Forum

Installed new tachs (teleflex),when I removed the old I installed the new ones the same way,except I needed to snip the bulb from the original harness and put a ring connector on it cause the Teleflex Tachs have a separate post for the light,and for the ground.Other than that it was ground,sender and ignition,I fired the motor...nothing,Tach was dead. I took off the sender wire and ran a dedicated separate wire from the sender post to the back side of the Tach and it worked?? Why wouldn't the original sender wire in the harness work,if it worked in the old tach's ??

I guess nobody knows

That is puzzling.

All I could think of is possibility of mixing up the wires when you had things undone and are not using the right sender wire, or maybe pulled something loose or shorted something if you were tugging ont he harness at all. Something changed between when it last worked for the old tach and wiring it up to the new one.

The simple answer is you can't be getting a signal throught the original wire; broken somewhere when removed (brittle), corrosion, bad connection at plug (pulled a pin). It's called Murphy; when the opportunity presents itself, he will step in and make things difficult for you

No brittle wires,made sure I put wires on the right posts(only two on original,(ignition-sender) . I think you're right D, Murphy's Law! Thanks for the reply's.