Tilt trim wiring

[Mr. Reese]

I have a 77 johnson 70hp with a 3 wire tilt trim. The previous owners had the TT directly wired to the switch with no solenoid. I have purchased a solenoid and a new BRP controller. My concern is the thinner wire for the switch in the new controller. Would it be better to install relays instead of senoid?

 

[alldodge]

In most all cases its always better to use relays/solenoids then to use full power to a switch. The issue is corrosion and voltage drop. Using relays allows for the high current to remain at the motor

That said, if wire is sized correctly and there is no corrosion, it works just fine

The old motors many didn't use relays/solenoids

 

[Mr. Reese]

In most all cases its always better to use relays/solenoids then to use full power to a switch. The issue is corrosion and voltage drop. Using relays allows for the high current to remain at the motor

That said, if wire is sized correctly and there is no corrosion, it works just fine

The old motors many didn't use relays/solenoids

Is one option better than another. Like do relays allow for thinner wire from the switch vs. The solenoid?

 

[alldodge]

Is one option better than another. Like do relays allow for thinner wire from the switch vs. The solenoid?

Yes, thinner wires can be used
Example: Motor may draw 20 amps at start up to full load. The 20 amps would require 12 gauge wire to from the pump to the switch. If a relay is used, it only needs 12 gauge from motor to relay, and relay to battery connections. Can use 16 or 18 gauge to/from switch to relay

 

[Mr. Reese]

Yes, thinner wires can be used
Example: Motor may draw 20 amps at start up to full load. The 20 amps would require 12 gauge wire to from the pump to the switch. If a relay is used, it only needs 12 gauge from motor to relay, and relay to battery connections. Can use 16 or 18 gauge to/from switch to relay

Ok thank you

 

[Chris1956]

Relays and solenoids are a bit different. Relays connect wires when energized and when not energized. That is ground is connected to the trim motor when the relay is not powered. When the relay is powered, it connects power to the trim motor. Relays use a 2 wire trim motor, where polarity is reversed to make the motor run in the opposite direction.

Solenoids are open when not energized. They provide power to the trim motor when energized. The trim motors used with solenoids have three wires and the center winding is always grounded. power is supplied to the outer windings, one at a time to spin the motor CW and CCW.

So what kind of power trim motor do you have? Likely it is 3 wire.

 

[Mr. Reese]

Relays and solenoids are a bit different. Relays connect wires when energized and when not energized. That is ground is connected to the trim motor when the relay is not powered. When the relay is powered, it connects power to the trim motor. Relays use a 2 wire trim motor, where polarity is reversed to make the motor run in the opposite direction.

Solenoids are open when not energized. They provide power to the trim motor when energized. The trim motors used with solenoids have three wires and the center winding is always grounded. power is supplied to the outer windings, one at a time to spin the motor CW and CCW.

So what kind of power trim motor do you have? Likely it is 3 wire.

I have a 3 wire and have been looking at the conversion kit to change to relays.

 

[alldodge]

All trim motors are 3 wire that I've seen. My old Chrysler OB's, one uses direct wire to a switch and another uses 2 relays. They both work

 

[Chris1956]

3 wire trim motors usually use solenoids. They do not need relays, although, I think you could get them to work. However, I do not see the advantage of using relays on 3 wire PTT motors.

Most newer PTT motors are 2 wire. Relays are required for these to operate. When you buy these for an older motor, make sure you get a conversion kit which includes a new wiring harness and 2 relays.

Both 2 and 3 wire PTT motor could be wired directly to a switch. It would need to be a really heavy switch, say 75Amps or higher. The 3 wire motors could use a SPDT switch. 2 wire PTT motors would need a DPDT switch, also rated at least 75Amps.

 

[Mr. Reese]

3 wire trim motors usually use solenoids. They do not need relays, although, I think you could get them to work. However, I do not see the advantage of using relays on 3 wire PTT motors.

Most newer PTT motors are 2 wire. Relays are required for these to operate. When you buy these for an older motor, make sure you get a conversion kit which includes a new wiring harness and 2 relays.

Both 2 and 3 wire PTT motor could be wired directly to a switch. It would need to be a really heavy switch, say 75Amps or higher. The 3 wire motors could use a SPDT switch. 2 wire PTT motors would need a DPDT switch, also rated at least 75Amps.

My main concern is the thinner guage wire on the controller. I have purchased a solenoid and the relay conversion kit. I would prefer the solenoid as long as the co troller wire will be able to handle the load. Not sure how many amps it takes to activate the solenoid.

 

[Chris1956]

Solenoids can be energized by about 3A. The PTT wiring in the controller should be sized to handle that.

So are we clear now? 3 wire PTT motors use solenoids. There is no reason to use relays. 3 wire motors have two windings with a center ground. The unused winding in a 3 wire motor is expected to be open. A relay will ground it, thus standard relay wiring may short a 3 wire motor.

 

[Mr. Reese]

Solenoids can be energized by about 3A. The PTT wiring in the controller should be sized to handle that.

So are we clear now? 3 wire PTT motors use solenoids. There is no reason to use relays. 3 wire motors have two windings with a center ground. The unused winding in a 3 wire motor is expected to be open. A relay will ground it, thus standard relay wiring may short a 3 wire motor.

Yeah I understand. The only thing I was unsure of was how many amps it took to operate the solenoid. Didnt want to burn up my new controller. Thats the route I will be taking. Thanks for all the info