Trim & Tilt Switch question '79 Evinrude

[allemann]

I'm trying to cobble together (on a tight budget) a jet jonboat with a '79 Ev 85hp, that runs OK.
The transom bracket has a wiring harness for the tilt indicator (which I won't be using)
and another heavier harness with the 3 wires for powering the tilt motor. The t/t works fine with test connections. It looks to me like the harness was meant to be used with a separate t/t switch rather than one on a remote control handle. A separate switch is fine with me and I can easily mount it on the console.
My control is from an '88 (2 wire t/t) and I don't think it can be wired for t/t to the old motor anyway.
I could make a switch, but are there reasonable cost aftermarket switches available? Or does OMC still sell a switch for 3 wire?
thanks,
bill

 

[tashasdaddy]

Re: Trim & Tilt Switch question '79 Evinrude

it requires a relay box, with a solenoid in it for the up feature. the 3 wire are hot up, ground, hot down.

 

[ezeke]

Re: Trim & Tilt Switch question '79 Evinrude

The problem is running that much power through small wires from the motor to the helm and back.

You can use a pair of solenoids, a reversing solenoid or a single solenoid. The original had a single solenoid for raising the motor and ran the motor down through the control switch without a solenoid because it took less power.

Does your control have a switch on it? If it does, you can use it.

 

[allemann]

Re: Trim & Tilt Switch question '79 Evinrude

The problem is running that much power through small wires from the motor to the helm and back.

You can use a pair of solenoids, a reversing solenoid or a single solenoid. The original had a single solenoid for raising the motor and ran the motor down through the control switch without a solenoid because it took less power.

Does your control have a switch on it? If it does, you can use it.

My control has a t/t rocker switch on it, but it is from an '88 with a 2 wire system, and the newer engine wired the t/t switch thru the main wiring harness (round) connector. On the '88 there are two separate pigtails and fittings inside the cowling that connect to the trim motor and gage. The old '79 motor does not have those connectors so there doesn't appear to be a good way to route the trim motor wiring back into the main wiring harness. The old trim motor wiring looks like it's meant to go externally to the console area.

The trim motor wiring has about 12ga wires, black, green, blue.

I ordered a dash mounted switch OMC #172899 that looks like the right application for '79, but I haven't found anything yet in the parts diagrams, etc about solenoids. I understand the purpose, but is this an OEM part you're speaking of, or an aftermarket upgrade to take the load off the dash mount switch? If solenoids were OEM, where were they?
Thanks,
Bill

 

[ezeke]

Re: Trim & Tilt Switch question '79 Evinrude

The PT&T control handle switches for the two wire PT&T motor have three wires; one incoming positive voltage and two going back to operate the PT&T relays depending on which way the rocker switch is moved.

That is same basic switch wiring used on the three wire PT&T motor except that the original 1979 solenoid box was mounted on the transom or near it and did not have relays but rather had a single solenoid.

Here is a link for the typical wiring of the later two wire models: http://www.maxrules.com/graphics/omc_pics/wiring/TnT_87_UP.jpg

Click the thumbnail for the basic wiring of the three wire PT&T in 1979:

 

[allemann]

Re: Trim & Tilt Switch question '79 Evinrude

just curious about the later motors with 2 wire pt&t... Do they have a relay mounted inside the trim motor bracket? I'm assuming then, that the relay connects motor load to a +12v screw on the terminal strip inside the motor cowling.

I still have the '88 here for parts (except the trim and bracket assy). I would imagine I could use the starter solenoid for the pt&t UP wire on the '79 ?

by the way, thanks for the jpg.

thanks
bill

 

[ezeke]

Re: Trim & Tilt Switch question '79 Evinrude

On the more recent motors the black relay box was usually mounted on the engine.

You could probably use the relay system from the newer motor if you can figure out how to rewire it.

The newer box basically used relays to switch polarity on the two motor wires to make it run one way or the other.

See the Arco diagrams; they might help: http://www.arcomarine.com/xhtml/tech tilt trim motor tips.pdf