Tachometer ?s

[alexjoe333]

Where does one hook a portable tachometer on the motor...how does one do it...and where can i purchase one for a reasonable price?

Here's my motor info:

1991 Mercury 40 HP (4 cylinder), serial # 0D041539, Model # 1040412LD, version ELPTO

 

[Mac uk]

Re: Tachometer ?s

Some controllers have a tacho connector on the front of the unit, that you can connect into.

 

[Barnacle_Bill]

Re: Tachometer ?s

Google up Tiny Tachs.

 

[alexjoe333]

Re: Tachometer ?s

okay...what "controller"? I have a maintenance manual...and besides it saying to connect a tach, it doesn't say where or how? So i'm a little lost

 

[Moody Blue]

Re: Tachometer ?s

The controller that was mentioned is the throttle/gear shift box. You did not mention whether your motor is a tiller type or not. Typically, the tach signal is already carried to the "controller" in the factory wiring harness. You need a "tach harness" to connect from the controller to the tach itself which is usually installed in the dash. The harness picks up all the required circuits from the controller and hooks up to the tach in the dash.

Alternatively, the tach signal can be taken from one of the two rectifier terminals on the motor (if you are connecting to a typical tach). You will also need switched +12V and ground on the tach for it to work.

The tiny tach that was mentioned has a single wire that wraps around the #1 sparkplug wire and takes the signal from there. It also needs 12v to operate.

 

[Riverman128]

Re: Tachometer ?s

The Tiny Tach does not need a 12v power source. It has it's own internal battery. Hook up can be tempory or permanent. Single wire wraps around #1 cylinder. I installed one on my 25HP Merc. this summer and love it. I installed it on the tiller arm with black zip-ties and ran the pick-up wire through black plastic wireloom and into the engine housing. It almost looks factory. It shows RPM (2 second delay) and hours operated. Get the model for multi-cylinder engines.