tackomiter wireing

[MWick]

I have a yamaha pro 50 hp 2/stroke that came on the boat with a tackomiter. I also have a yamaha 25 hp 4/stroke that didn't come
with a tack.When I change motors I would like to hook up the tack
so I would know what rpm I am running on the 4/stroke 25 hp .
The 4/stroke 25hp is a year 2000. The tack is a yamaha with a low
oil light for the oil injected 50 hp 2/stroke.
Will this tack work on the 2/stroke and the 4/stroke?
Will there be a tack wire on the 25hp 4/stroke?
thank you for your help
MWick

[boats.net]

The rpm's will read(if change setting on back of gauge to 12 pole) but the oil light wont function properly. Would need a new tach if want warning lights to work. Is this an analog tach or digital and what year is the 50?

[MWick]

tack wireing ?

The tack is analog and the pro 50 hp 2/stroke is a 1989. I am just interested
in knowing the rpm's I am running on the 4/stroke 25 hp (yr 2000) so I can
change props and stay in proper rpm range. The 25 hp 4/stroke has a warning light on it.What about the wireing on the 25 hp 4/stroke, does it have
tack wireing under the cowl and if so what color do i look for?
Thanks again for your help
MWick
Thanks agin for your help

[boats.net]

Tach wire is in main harness, just connect keyswitch main harness to engine.

[MWick]

tack wireing ?

The 25hp 4/stroke is a tiller model.There is no key wireing harnes.
Thank's for your help
MWick

[boats.net]

Have to splice into the green wire at stator of outboard for tach signal and connect to tach signal post on tach but will also have to run a ground wire from battery to tach and install a wire from battery positive to a off/on switch and from switch to tach to be able turn tach off.