1974 Mercury 1150 stator good or bad?

nature1100

Seaman Apprentice
Joined
Aug 1, 2012
Messages
46
I have a 1974 Mercury 1150 (Inline 6 cyl 115HP) that I just restored. I put a tach into my boat and installed as specified by the manufactor's instructions. I confirmed that the tach signal wire was attached to one of the yellow/red wires on the rectifier and the tach is set to 6C which is half of the 12 cores on the stator. When I started the outboard, the tach read 0. I then switched the tach signal wire to the other yellow/red wire and restated the outboard. Still 0 on the tach. I then took the tach wire and tapped it on the +12v red wire to simulate alternating (pulsing) voltage and the needle moved, so the boat wiring and tach are good.

How do I verify that the stator is good? It is only a battery chage only stator. Has only 2 yellow/red wires coming out of the stator.

I have removed the 2 yellow/red wires from the junction block on the head. Checked continuity between ground and each wire and got nothing. Then checked continuity between the 2 yellow/red wires and it has that. Checked resistance between the 2 yellow/red wires and it is 0ohms.

Do I have a bad stator or is it the rectifier? Or is there additional troubleshooting steps that i have to do?
 

calvinator

Petty Officer 1st Class
Joined
Sep 22, 2010
Messages
286
Re: 1974 Mercury 1150 stator good or bad?

I have a '75 Merc 1500 and just did similar troubleshooting.

On your rectifier, try both terminals coming from the stator yellow/red wires. On my rectifier, the bottom terminal produced no tach signal, but the left terminal did.
 

nature1100

Seaman Apprentice
Joined
Aug 1, 2012
Messages
46
Re: 1974 Mercury 1150 stator good or bad?

Tried both terminals on the rectifier and still nothing. Also my voltage gage only reads 12 volts even at WOT.
 

MH Hawker

Vice Admiral
Joined
Jul 13, 2011
Messages
5,516
Re: 1974 Mercury 1150 stator good or bad?

Then its not charging and it may well be a bad stator
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,003
Re: 1974 Mercury 1150 stator good or bad?

The rectifier could be shorting the stator voltage to ground. Disconnect both yellow red wires from the rectifier and connect each in turn to the grey tach signal wire. Run the motor and note the tach reading. if you have a voltmeter, set it to 100VAC and test the stator output, with the rectifier disconnected from the yellow/red wires. Step down the voltage scale until you see some AC voltage. The stator output will be across both yellow wires, not from one to ground.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,003
Re: 1974 Mercury 1150 stator good or bad?

I misspoke. The tach signal wire is likely brown, not grey.
 
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