Tach wiring

[GreenLakeBayliner]

I’ve got a 1991 Bayliner 1800 capri with a 1994 Evinrude 150 V6

tachometer doesn’t work

Taking a quick look at the cabling on the back of the tach I have a purple wire which looks to be power jumping between gauges, A gray wire which looks to be the one that connects to the rectifier on the motor and a ground wire

At the motor I see the gray wire is connected to the rectifier but the purple coming from the harness doesn’t have anything to connect to. I’m not sure what this is for

anyone have any thoughts?

 

[Chris1956]

Purple is ignition power. It originates at the ignition switch, goes back to the engine to provide power to some sensors and is used to power the gauges.

 

[He rik]

Purple is ignition and, if you have the tach connectid thrue the remote, 12V to gauges as described above.

Gray is tach-pulse, it should be connected to rectifier gray on the engine terminal, you can move that wire from gray from rectifier to the yellow-gray from the stator (mine old -82 has the tach connected there ) , if the tach works your rectifier is bad, if not maybe you need a new tach or bad wireing, this goes for older/carburated engines in general as I understand it and been able to find out.
Newer with fuelrails Im not certain.

 

[oldboat1]

Is the charging system working?

 

[GreenLakeBayliner]

Charging system seems to be working just fine. Neither the tack or the speedo work at the moment

there doesn’t seem to be an obvious mate to the purple connecter coming from the harness.

can I assume that that purple connecter currently orphaned is meant to deliver 12 bolts back towards the gauges? If so is there harm in connecting it to the positive terminal of the battery for a basic a test

 

[He rik]

Should be ok, unless there is a shortage somewere and the lead just burnt off, then it could be a problem to feed 12V "backwards".

Take a multimeter and check purple for 12V instead.
If you dont have 12V on gauges check the wires, from ignitionswitch to gauges, if you have 12V on the ignitionswich but nothing on the gauge, replace the wires.
If the motor starts you do have 12V to the ignitionswitch purple.

If charging ok you should have aproximatly 13,5V on ideling over battery and upwards high 14V on higher rpm.

If you dont have a lot of things connected a healty battery manage a lot of starts before it wont start again whitout charging, ignition have its own power and dont feed from battery so as long it starts it will keep on running until the fuel run out even if you throw the battery overboard.

So, have you checked charging? And How?