2 wire controls to 3 wire system (reverting)

[iloveketchup]

I'm in the home stretch replacing an '85 looper (blown) with a '76 crossflow. I got the thing running, new thottle and shift cables adjusted now i just need to get the trim working.

TRIM:

i know the old uses a 3 wire system, the new uses a 2. Its actually easier for me in terms of $ and placement of the trim relay to use the 3 wire motor. I have the harness for the 2 wire still so i don't need to splice, hack, and slash the control harness if it helps.

I know either the up or down trim doesn't use the relay. i think it just sends power through the trim switch in the control arm. That makes me a little concerned for heat/fire and contact ratings. I don't know how much current is going to the motor nor the ratings of the contacts. The wires seem thin too.

If i used the harness off the 2 wire controls, is the harness going to have a heat issue? E.g. is the gauge size high enough for running the motor without the relay?

Also, does anyone have a schematic showing how i'd convert this? I have a few but they only really show local. I don't have a helper to test the switch.

Thanks

if there is somewhere that explains how to do this, a link is welcomed.

 

[HighTrim]

Re: 2 wire controls to 3 wire system (reverting)

 

[Chris1956]

Re: 2 wire controls to 3 wire system (reverting)

It would be simple enough to substitute 2 solenoids for the 2 relays. You would wire the motor's green wire to the down solenoid and the motor's blue wire to the up solenoid. Now ground the motor's black wire.

The up switch should send +12VDC to the up solenoid. the same for the down switch...

 

[boobie]

Re: 2 wire controls to 3 wire system (reverting)

You don't really need the down solenoid (green wire) but it's not a bad idea. If I remember right Yamaha had plain old solenoids for both up and down also rather than relays.