Yamaha 70 Tach

Big Mule

Recruit
Joined
Jan 31, 2009
Messages
3
Hello Folks,Been reading here in the forum a lot in the past few days and I still not satisfied with what I've read.I have just re-powered from a evinrude to a yamaha and I can't seem to get the tach to work with the yamaha.Here's what I got 70 ETLG 1988 MODEL With a 703 control .I know green is pulse yellow is power and black is ground That's how I have it hooked up.Now I have read here in the forum that I need it set to a 3 p setting since it is a international Teleflex tach,I,ve done that.Still No reading and I know the tach was working with the OMC moter set @ 6.Been reading more and have saw where that in several posts that they are telling folks they need a converter box for these early 3 cyd's to work also I saw where folks had asked for a part # for a converter box and no one had give a # to where you could get one.So my Big Q is this,Would I not be better off to get a OEM tach (analog) for this engine.Wish someone would let me know there input on this matter because this is a fresh rebuild and I have yet to put in the water`for a run up and I was sure not wanting to over rev it at all.Guess I will stay tuned till someone reply's.
 

Big Mule

Recruit
Joined
Jan 31, 2009
Messages
3
Re: Yamaha 70 Tach

Well,Is anyone out there willing to try and help?Let me ask this Q:With a OM meter what kind of reading should I have on the green tach lead coming out of the control box.Trying to make sure that the tach lead (green) don't have a BREAK or a bullit conecter bad some where between the 703 yamaha control box and conection at the stater hook ups.:confused:
 

Big Mule

Recruit
Joined
Jan 31, 2009
Messages
3
Re: Yamaha 70 Tach

O.k. Folks, I have got a OEM Tach, That should work for this motor.But I am unsure where the Green tack lead hooks to the back of the tack and the yellow keyed wire hooks to the back of the tack.these are some pic. of the tack.1 pole has 12 above it and the other doublewd pole has a (B) above it and the pole on the right side by its self has a (G) for ground ? Some one let me know what goes where to be sure. Thanks,Big Mule
 

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rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Yamaha 70 Tach

cant help ya here.
that tach is from the 80's someplace and I was working on gray boats then not play boats.
 

zebu14

Cadet
Joined
Nov 25, 2009
Messages
6
Re: Yamaha 70 Tach

Hi,

I've the same Tach but I don't manage to have it running...

Do you solve your problems ?

Can you indicate me how to plug it in order to have it running ?

Thanks !
 

kaferhaus

Petty Officer 1st Class
Joined
Dec 17, 2008
Messages
250
Re: Yamaha 70 Tach

g is the signal wire

b is the ground wire

12 is the lead to the "acc" terminal on the ignition switch.
 
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