Need wiring help for 3 wire tilt and trim for 1985 85hp Force

[rlasiak]

I just bought a 1985 85hp Force. I have three wires coming from my tilt and trim and I don't know how to wire this. There is a blue/white, green/white and black. I have no switch or anything. Just the wires coming from the motor. I'm assuming the blue wire is up, the green wire is down and the black is hot. So can I get a two way switch and wire the green and blue directly to the switch and the black to the battery then to the switch? Is that the proper way to do this? If not please help. Thank you for your time.

 

[Jiggz]

Re: Need wiring help for 3 wire tilt and trim for 1985 85hp Force

Actually in a 3-wire motor, the black wire is the common of negative wire while the blue and green are the up and down wires respectively. With the black wire directly connected to ground, a momentary normally open three pole switch (rocker type spring loaded) connects either the blue or green wire to the positive wire to raise or lower the engine. Here's a simple diagram of the motor.

 

[jerryjerry05]

Re: Need wiring help for 3 wire tilt and trim for 1985 85hp Force

You need to supply a hot lead to a 3 position spring loaded momentary switch.
Then hook up the blue/green to the posts on the switch.
You have a switch on the dash?
Like Jiggs said the black is a ground.

 

[Frank Acampora]

Re: Need wiring help for 3 wire tilt and trim for 1985 85hp Force

Since the three wire system puts the full amperage draw of the motor through the switch, you absolutely need at least 10 gauge wire.

The three wire system CAN be converted to relays quite easily. The ONLY thing you need to do is insulate the heavy ground wires from the relays and connect the ground from the motor to either the engine block or the battery negative terminal.

While it does work, the three wire motor is less efficient because only 1/2 the motor windings are used to turn the motor in either direction.

If you elect to keep the three wire system, you MUST run a 10 gauge red wire from the battery positive terminal to the center terminal of a M-O-M switch (Radio Shack-- Double pole, double throw 30 amp capacity. About 4 bucks as I remember). Black from the motor is attached to the battery negative terminal. Then, a green 10 gauge wire is run from the top of the M-O-M to the green motor wire and a BLUE 10 gauge wire is run from the bottom terminal of the M-O-M to the blue motor wire. All wires must be connected to the terminals on the same side of the switch. The second set of terminals is not used and does not have any power.

 

[rlasiak]

Re: Need wiring help for 3 wire tilt and trim for 1985 85hp Force

Thanks for all of the help guys. I got it all wired up and it works great. I got a 20 amp double throw switch, ran my black directly to my battery, ran a 16 gauge hot wire from my battery to my switch and then connected my blue and green wires. Once again thanks.