Tachometer replacement issue

[Kschep]

I replaced old tach (that worked to a degree) - meaning it went up dnd down with rpm's but based on sound of engine working hard I sometimes questioned how accurate it was.
Regardless I decided to replace bec it was getting rusty anyways and needed replacing for aesthetics as well.

I installed new as directed. Following all directions. Not too hard, just matching the wires basically from old to new.
Fast forward to install being completed and all it wants to do now is: when I fire up the engine it flys up to the top and goes back to zero as I'm sure it should, but after that it will not give me any reading just stays at 0 like it's not functioning at all.

So I'm curious if anyone take gas run into this and be able to give me possible troubleshooting points that I can look at ?!

Thank you

 

[bhsdriller]

what tachometer are you trying to use

 

[1911]

Signal wire goes to the negative terminal of the coil, power wire goes to 12 v switched with ignition, ground wire goes to ground, and the gauge light goes to the headlight switch/interior lights dimmer rheostat.

 

[Kschep]

what tachometer are you trying to use

New vintage USA tachometer
newvintageusa.com


Like I said it jumps all the way up then just immediately back to nothing and no movement further after firing up. So there is some life so to speak.

 

[rlong]

The two obvious checks (and mistakes) are the signal wire on the wrong side of coil, and the dip switches are wrong (often not clear what end the 1-2-3-4 order starts at). If not those “it broke” (the start up sweep would infer it has power and ground).

 

[Kschep]

The two obvious checks (and mistakes) are the signal wire on the wrong side of coil, and the dip switches are wrong (often not clear what end the 1-2-3-4 order starts at). If not those “it broke” (the start up sweep would infer it has power and ground).

Ok thx for that info - I'll make sure to check that as well. Much appreciated