Repower 1987 20’ Sunrunner

Andy Spidal

Cadet
Joined
Jul 27, 2018
Messages
6
I have a 1987 Sunrunner 20' that I purchased with a cracked engine block. The engine that came with it was a Mercury 5.0. I installed a Mercury 260 (Chevy 350). I am trying to figure out the wiring.

On the starter it had a yellow/red wire on one terminal start I assume, purple and yellow wire on the other terminal, purple to points, yellow to electric fuel pump. The fuel pump seams wrong, power all the time when key is on, relay out of the circuit?

I replaced the distributor with a non point distributor, I no longer need the ballast resistor can I just splice the wires that the resistor connected to together.

On the power lug of the starter there was a red wire and 2 black wires this seams wrong. There was a black wire going to battery switch this explains 1 black wire. The wire harness has 1 red wire and 1 black wire that looks like it is to short to go anyplace but to the starter does Volvo use black for power sometimes and not always red like I am used to? I am going to pull out my multi meter and trace the wiring as best I can. I cannot find a wiring diagram for my boat anyplace and I am afraid that the person who came before me has it jury rigged.

One last question my lift pump power was not connected I assumed it went to the battery terminal on the starter (large center post) but the lug on the starter is larger than the lift pump terminal. I can drill out the lug to make it fit as I don't see any other place to connect it other than strait to the battery.

I have a service manual for the Mercruiser I am thinking about cutting the wire harness apart and wire it according the manual as best as I can.
 

garbageguy

Lieutenant Commander
Joined
May 8, 2012
Messages
1,598
maybe you've already been thru this, but before more $ and time into propulsion, are you confident the boat's hull structure is sound, and safe to be out on the water? There's a lot of good info on this site about that.
 
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