Volvo Penta wiring

[aspidal]

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.

 

[makomark]

"... 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...."

Trying to get the big picture here...so where did a Volvo product enter the picture??

Are you replacing just the engine and trying to reuse the original wiring harnesses?

 

[aspidal]

Trying to get the big picture here...so where did a Volvo product enter the picture??

Are you replacing just the engine and trying to reuse the original wiring harnesses?

The boat has a Volvo 290dp outdrive. I am using the original wire harness. This is the second engine replacement that I know of. I have a service manual for the Mercruiser engine. I might be better off just pulling the wire harness apart and starting from scratch.

 

[makomark]

On the electric fuel pump wiring, there are a couple of acceptable approaches that are used...and wiring it so the pump runs when the KEY is in RUN is NOT ONE OF THEM...I'll see if I have a simple circuit that I can paste easily. the simplest approach is to use an oil pressure switch that allows the pump to run once the engine is running and has established oil pressure.

On bypassing the ballast resistor, you can do that but you need to verify that the COIL is happy without the ballast resistor (vs just having an electronic distributor)...

Volvo has done some non-standard wiring on occasions...tracing your black wire is probably the best approach on that one.

On the 'lift pump' - not sure exactly what you are referring to there...in general, you can resize a lug if needed but it's not optimal.

 

[makomark]

You can use PURPLE wiring for the unlabeled wires going to the fuel pump...with a black wire for the ground....

There's another variation where the oil pressure switch uses a SPDT configuration same end result...