1974 Merc/Ford 351w 255hp ign/coil wiring

[Hawk78]

I have a 1974 sea-ray 240 with ford 351w I had to re-assemble the motor from a box full of parts. I am trying to figure out the coil wiring. I have a mallory points dist it has a black wire coming out of it, does that go to the positive or negative on the coil. I also have two tan wires stuck together coming from the wiring harness are they posi or neg to coil? and one black wire from the harness posi or neg? also one green wire from the harness but i believe it goes to the temp sensor. Does anyone have one of these that can maybe shed some light on these wires? I'm pretty sure these are the stock colors but i cant find a wiring diagram anywhere for this motor.

 

[chargerboy]

Re: 1974 Merc/Ford 351w 255hp ign/coil wiring

Both your black wire should go to the negative, tan wires should go to positive, not sure of green. That's how it's hooked up on my old ford truck with the same ignition and engine.

 

[chargerboy]

Re: 1974 Merc/Ford 351w 255hp ign/coil wiring

It's a ford 351 Windsor, same engine, different name.

 

[frank246]

Re: 1974 Merc/Ford 351w 255hp ign/coil wiring

Black from distributor (points) to neg on coil.
Black out harness (shift interrupt) to neg on coil.
Gray from harness (tacho sender wire) to neg on coil.
Purple (ignition) to pos on coil.
Purple-yellow (ballast risistor bypass from solenoid) to pos on coil
Tan out harness to temp sender.

Merc color codes:
BLACK (BLK) All Grounds
BROWN (BRN) Reference Electrode-MerCathode
ORANGE (ORN) Anode Electrode-MerCathode
LIGHT BLUE/WHITE (LIT BLU / WHT) Trim- ?Up? Switch
GRAY (GRY) Tachometer Signal
GREEN/WHITE (GRN / WHT) Trim -?Down? Switch
TAN (TAN) Water Temperature Sender to Gauge
LIGHT BLUE (LIT BLU) Oil Pressure Sender to Gauge
PINK (PNK) Fuel Gauge Sender to Gauge
BROWN/WHITE (BRN / WHT) Trim Sender to Trim Gauge
PURPLE/WHITE (PUR / WHT) Trim-?Trailer? Switch
RED (RED) Unprotected Wires from Battery
RED/PURPLE (RED / PUR) Protected (Fused) Wires from Battery
RED/PURPLE (RED / PUR) Protected (+12V) to Trim Panel
ORANGE (ORN) Alternator Output
PURPLE/YELLOW (PUR / YEL) Ballast Bypass
PURPLE (PUR) Ignition Switch (+12 V)
YELLOW/RED (YEL / RED) Starter Switch to Starter Solenoid to Neutral Start

 

[Bt Doctur]

Re: 1974 Merc/Ford 351w 255hp ign/coil wiring

Have you checked in the Adults Only section for the manual?