85 hp force tilt/trim wiring

[spserg]

Greetings all! I have 2 1987 Bayliner bass boats, both with Force 85hp outboards. One boat is in much better condition, but with a heavily damaged skeg and questionable motor. My old Bayliner is very rotten but with a great running outboard. I am in the process of swapping them out as we speak. The boats are identical, but the tilt trim assemblies are different (same years) the motor I am installing uses a series of relays and appears to run off the main harness. The motor being removed has a direct factory connection to the tilt/trim motor with no additional relays installed under the cowl. The harness runs directly through with the cable bundles and appears to have fusible links. I have not checked under the dash, but I believe this is a direct wire connection. Would there be significant risk is connecting directly to the t/t motor as previously done? Both are 2 wire set-ups. Thanks!

 

[spserg]

BTW, to be specific the factory wiring harness does indeed have 3 wires but when I pulled the old motor, only 2 were in use. The 3rd appears to not be used.

 

[jerryjerry05]

Pic of the 2 different setups??
You'll need 3-5 posts before you can add pics.
Use of a pic sharing site helps.

Connecting it direct might cause the wires to get hot.

The setup with the relays was a good idea but came with problems.
The connectors and relays would gunk up and loose contact.

The wiring harness? what color wires?
Should be Blue/up Green/down

If possible use the one with the relays.
It provides a better connection and the heavy wires won't heat up.

 

[spserg]

The wiring to the pump on the boat is blue/green-yes and prob 12 gauge. The connection to the relays on the new motor are also blue/green. The boats wiring directly to the motor is heavy gauge, while the relay connections from my old boat are smaller possible 18 gauge. I'm wondering if the best plan may be to just run the blue/green heavy gauge to the relays-leaving them intact. Ill push to hit that 3 posts and put some pics up!

 

[jerryjerry05]

It wouldn't hurt to use the heavy wires.

 

[spserg]

That was my train of thinking. So even if its heavy gauge wire, and the dash toggle it will still provide the 12 volts to work the regulator. It just wont be the heavy draw, just the 12v signal.

 

[spserg]

Hopefully pics today after work.

 

[spserg]

I have pics, but working on uploading. In a nutshell, the original wiring harness has 10 leads, 2 of which are for tilt/trim. The new boats harness has 8, and the t/t is run direct. I assume that it was a factory or dealer add-on. My hunch is that running the leads to the OB t/t relays will work the units correctly. Any thoughts??

 

[jerryjerry05]

The 10 lead harness is the 'newer" one.
The wire in it is strong enough to run the T@T as long
as the electric motor is in good shape.

The 8 lead was used on the early 87 and before.
The switch was installed on the dash.
Then they installed the trim switch in the handle and incorporated the extra wires in the harness and
used the relays to keep the leads from getting hot during use..

 

[spserg]

I never was able to post pics, my apologies. However, I was able to complete the motor swap and ran cables to the existing tilt/trim relays. It works like a champ! Now if I can just get everything else wrapped up for the 4th!!