Hooking up trim and tach gauge

[Woody1594]

I have a 1989 90 horse 2 stroke that I'm trying to figure out how to attach the tach and trim gauge wires along with the oil. I have a analog tach with the oil and over heat lights the part number for the tach is 6Y7-83540-80-00. Coming from the motor there are 3 wires orange,pink and a black. Are these the trim and oils leads?

At the control box there are 2 groups of wires. The first group as 4 wires 2 yellow 1 black and 1 pink. The 2nd group also has 4 wires 1 yellow 1 black 1 red and 1 green. This is a repose the boat use to have a evinrude on it. Thanks for any help.

[boscoe99]

Have all for the controls and wire harnesses in the boat been replaced with Yamaha stuff?

Yamaha stuff is plug and play. If you are trying to go from a Yamaha motor to Evinrude stuff and then to a Yamaha gauge that is a different issue altogether.

If the latter, you might want to go back to the motor and see what wire colors are coming from the engine harness and what goes into the boat.

In the main Yamaha ten pin connector, yellow from the motor is key on battery power. Black is battery ground. Green is the tachometer signal. Pink is the buzzer warning ground.

Yamaha uses other harnesses and wire colors for trim and light activation in the gauges.

Without knowing where you are starting from it is hard to give directions as to which way to go.

[Woody1594]

I'm switching everything over to yamaha. I have a 703 control box and just got the tach in the mail today. So all the evinrude gauges and wiring are gone. I also got a wiring harness today that goes from the control box to the gauges.

[boscoe99]

Paging Mr. Rodbolt. Paging Mr. Rodbolt -

Have you ever installed a newer version of the analog tachometer (low oil light and over temperature lights only) and trim gauge on a pre 1994 model motor?

I see several issues. No 5 volt reference from the tachometer to the trim sender. Not sure if this model outputs a ground to turn on an over temperature light?

What say yee?

[throrope]

I replaced our fuel gauge with a trim gauge on our '06 tlr 90. The trim sensor is a lever driven variable resister on the left side of the mounting plate visible with the motor tilted up looking at the transom from behind the boat. Wires to the harness easily traced. I recall only one required to the console if a common ground and 12v availablea at the console. Adustment was tedius trial and error at the sensor. Worth sharing a cold six with a buddy. The funny is the fuel and trim gauge are exactly the same save the dial decal.

I suggest new throttle and shift cables. After fighting mine for a year plus, I learned they are a wearing maintenance part changed out in twenty minutes.

Hope this helps and keep us posted.

[boscoe99]

Your motor uses a two wire sender. Variable resistor. OP' s motor uses a three wire sender. Potentiometer.