Mercruiser Electrical - How It Works (Read the Description) 

i’m having a starter issue as well

Hello

Are all the threads installed in the same screw, red, orange, yellow and purple?

Are all the threads installed in the same screw, red, orange, yellow and purple?

Please reply, thank you❤❤❤❤❤❤❤

If you have the serial number of the engine go to www.marineengine.com and put in the serial number. That will bring up a schematic of your system. The serial number is a metal tag on the block just above the starter.

@@moccasinmarine appreciate your time!!

I will say that 95% of the bolts in a GM small block (4.3 is a small block with 2 cylinders less) are 3/8”x16 of varying length.

I would go directly to the battery.

@@catfisher420 I figured it out, thanks.👍🏿

I would need a photo to answer this question. Send me a photo to gmefiguy@gmail.com

@@moccasinmarine coming at cha! much love!

​@Moccasin Marine LLC did you get an answer to this question?

I would also like to know what the answer was as I have the same. A black wire and a purple wire that can't be accounted for.

I have the same problem. Tested the oil pressure switch, ohms and volts are good, diaphragm was bad. Jumped the switch with a paper clip and my fuel pump worked/buzzed. I believe the starting/default position for the oil switch is open, then gets 4psi to close circuit, passes juice/volts to fuel pump. Engine doesn't start, then with key in run position, not crank position, fuel pump is buzzing. So this must mean that after cranking, the motor maintains at least 4 psi... right? Is that possible:? 1 crank, 2 build pressure, 3 no start, 4 pressure of 4+ psi remains ?

@@mtbristol I'm pretty sure my oil pressure switch is bad. There should be a lot more than 4psi when the engine is running. If you only have 4psi of pressure then you have bad motor. Mine runs at 65psi of oil pressure when running. I just jumped the wires together so I have fuel as long as the key is on. My block is cracked badly in the valley. Fills the engine with water within 5 minutes and then a milk shake comes spewing out the breather hoses. Got the intake off now. Getting ready to JB weld it and see what happens. If it doesn't work then I'll be ordering a reman long block.

The starter circuit at the ignition switch is a different contact. The starter contact on the switch only turns on the starter relay nothing else. The starter then powers up the ignition through the purple wire on the starter. Once the engine runs and you let go of ignition switch the other contact (RUN) in the ignition switch powers the ignition and accessories on the engine and console.

@@moccasinmarine so how can I test the ignition switch to check for fault? Take a test lead from the yellow/red wire to the purple wire? Then turn key as if cranking?

Either that or a bad pump.

Neutral safety switch in shifter will not let start signal reach the starter relay. If that checks out connect 12v jumper wire to starter relay yellow/red terminal. If relay doesn’t engage either bad relay ground or bad relay. If relay does engage but no starter spin you have a bad starter or bad yellow red wire to starter. However, before any of the above, see if any accessories work in the gauge cluster, like bilge pump or blower or gauge lights, etc. if none of that works you may not be getting power to the steering console. That power is fed through pin 6 of the boat to engine harness connector. Pin 6 is fed from the main fuse at the battery cable connection at the starter.

The alarm is up under the dash panel. It sounds anytime the tan/blue stripe wire is grounded.

Someone had installed some type of rocker switch at my alarm under the dash

There is no relay because the pump is powered directly through the ignition switch, then through the driver kill switch, then through the oil pressure switch. During starting the pump gets power from the starter but during run the power comes through the oil pressure switch.

@@moccasinmarine Thank you. I'm on the final step with starting it. Does the fuel system need to be primed after replacing the fuel filter/water separator?

@@rsw0331usmc yes, jumper oil switch wires together, turn ignition switch on and pump should run. Run until fuel squirts from accelerator shots in carburetor. Turn off ignition and remove jumper.

@@moccasinmarine Thanks again. I did try jumping the pump directly with jumper wires from the battery. The pump did run in this condition but I still had no fuel delivery. I disassembled everything and looked for obstructions. There was not a drop in the filter, it did not draw any fuel at all. I wound up back-bleeding it with a large syringe and hose from the carb fitting back. That worked.

Purple and gray. I showed them in the video.

Double purple on positive double grey on negative