Tiny Tach on fuel injected outboard

[Iskander-M]

Hi all,

do anyone one has experience with fitting a Tiny Tach or equivalent on an fuel injected outboard? I have done it on the spark plugs which is very straightforward but wonder if this set up would work if you wrap the sender wire around injector ignition coil?

If not I see the only option to use another type of meter, epoxy the magnet to the flywheel and fit the sender through the plastic cover which I have done previously on myHonda BF20

 

[GA_Boater]

Tiny Tachs work the same for any spark plugged motor. No matter what fuel system, a plug wire is wrapped with the sense wire. You can wrap around an injector all day long and it will not work.

What Tiny Tach did you get that requires a magnet?

 

[Scott Danforth]

you need the 40,000 volts that goes thru a spark plug wire to trigger the very very very very very minute signal up the trigger wire to the tiny tach.

the 12 volt pulse from the injector wont do squat to trigger a tiny tach.... unless you fire the 40,000 volts from the spark plug lead thru the injector wire.... and fry your computer and injector.

 

[Iskander-M]

Thanks for your replies guys, all makes sense to me

What Tiny Tach did you get that requires a magnet?

it is not the Tiny Tach but another brand, you can find plenty on Amazon they are called “proximity sensor tachometer” which have a small strong magnet (I have epoxied it on flywheel) and the wired sensor (fitted through a drilled hole in the plastic flywheel cowl)

The magnet and the sensor must have 2-3mm gap between them otherwise the tachometer does not pick up the signal

 

[Scott Danforth]

on an EFI motor, why not simply plug in the Honda tach to the Honda motor.

 

[Iskander-M]

on an EFI motor, why not simply plug in the Honda tach to the Honda motor.

Just want to fit a tiller handle on it and ret rid of the wiring loom

 

[Scott Danforth]

the tach can be mounted on the cowl if you want.

it also has diagnostics.