What type of tachometer for 70 hp Force

[5string]

I bought the teleflex tach harness and a tach to put on my 93 - 94 year 70 hp Force motor. I read alot on the internet and found a chart that said I needed a 12 pole tach. Now this tach has a dial that says 1 2 3 4 and a sticker that says 1 = 4cyl and 2 = 6cyl 3 = 8 cyl and 4 = 12 pole. So I set it on 4 and hooked the gray wire to sender and the purple wire to batt and the black wire to ground. Started up the motor and all it does is set on 0, I reved it a couple time and nothing. Tach is new but I got it on Ebay so maybe the tach but I need to know if I have the right tachometer? Anyone have any ideas.

Thanks for any help 5string in NC

 

[Frank Acampora]

Re: What type of tachometer for 70 hp Force

First try running a separate power wire from the "I" or "A" terminal of the ignition switch to the tach.

Then get the schematics and find out which wire is actually the signal wire. HINT: It should come off one AC terminal on the regulator/rectifier.

Early Force used purple, Mercury sometimes used grey, so there is no telling which it actually is unless you have the schematics or have actually worked on the engine. I did work on one at the beginning of the season but I forgot the wire colors. sorry.