12 pole tach work on 12 pole alt.?

[Basszilla4]

Engine is a 1973 Johnson 65hp outboard. Looking at a Faria Chesapeake tachometer on eBay. I have found out that my engine has a 12 pole alternator. The tachometer has no selector switch on back for different pole settings. However, there is a sticker on back that says 12 Pole.

Only reason I ask is I had read on a website (Teleflex) that for a 12 pole alt., you set selector switch to half the poles. So a 12 pole would be set on 6P. That is Teleflex instruments though.

Being these instruments are not that cheap, I thought I would ask for advise before I go off and buy something that would not work for my application.

Any info would be greatly appreciated.

Sincerely,
Errol (Basszilla4)

 

[F_R]

Re: 12 pole tach work on 12 pole alt.?

There are poles and there are pulses. 12 poles is the same as saying 6 pulses. Just a matter of words.

 

[Basszilla4]

Re: 12 pole tach work on 12 pole alt.?

Beautiful. Thanks a million F_R.

For future reference, 12 pole tachometer will work on a 12 pole alt.? Only reason I ask is I might loose auction on eBay and will have to keep looking or would buy new. Just want to be 100% sure.

Thanks again for any info.

Sincerely,
Errol (Basszilla4)

 

[F_R]

Re: 12 pole tach work on 12 pole alt.?

12 pole tach, or 6 pulse tach, same thing. They just like to confuse us mortals. Actually, 12/6 is pretty much the norm. The other popular one is 10 poles/5 pulses.

 

[Basszilla4]

Re: 12 pole tach work on 12 pole alt.?

Ahh, I see. Yes, can be very confusing. Especially for a greenhorn like me. On the back of the tach, besides the wires for the lights, there is three wires coming off tach. Red, Black, and Grey. I know Red is for power, Black is ground, and Grey is pulse or signal.

My question is, what wire do you splice into on the engine for the signal wire. Again, motor is a 1973 Johnson 65hp 3 cylinder. I don't have a service manual yet. But seeming this engine runs like new, I think I will pick one up. Not sure if manual would even tell me this information.

Thank again for any info. Did I mention this website is awesome? I find so much useful info on here.

Sincerely,
Errol (Basszilla4)

 

[F_R]

Re: 12 pole tach work on 12 pole alt.?

Piece of cake. Pick up the 12v power from the key switch (purple), the tach signal from a gray wire already there in the control, waiting for you.
EDIT: The control is grounded. Connect your tach ground to it.

 

[Basszilla4]

Re: 12 pole tach work on 12 pole alt.?

See, isn't this website awesome?

Thanks F_R, I won the eBay auction for a brand new Faria Chesapeake Series speedometer, tachometer, and fuel gauge. $31.00 plus $11.00 for shipping for all three. Boat at the moment has no fuel gauge so I'm going to buy a universal fuel sending unit. Thats only two wires so it should be a piece of cake, I hope. Any pointers on hooking up the fuel gauge? Or, pretty much self explanatory?

Thanks again for any appreciated information.

Sincerely,
Errol (Basszilla4)