questions on magnapower + tach

[jvb]

ok, so i finally found a tach that claims to work with my 1973 chrysler 70hp. but, when really reading into this thing, it claims to not be able to work with magnapower type 1 ignition. i was told this is what i have. the tach lists my model as one that will work with a tach, but then it states it will not work with type 1. my service manual says hooking up a tach is doable, and give directions for an easy hookup. i was also told that this motor has 12 poles, and to set the tach for 6 pulses. so, the question is, can a tach actually work on a type 1 magnapower? looks like it will, but thetach directions make me believe otherwise. will i hurt anything just by trying?

 

[eurolarva]

Re: questions on magnapower + tach

It is possible that your model of chyrsler was availible with an alternator which the tach would probably work on. Your manual is probably talking about an original chrysler tach that would also work with it. From reading here on Iboats I believe you need to count the poles on your stator which I believe is 20. There was a link posted that was something like www.tinytach.com . Another option would be an induction type tach however mounting it might be tough. A sensor needs to see a piece of reflective tape mounted on your flywheel which could be dangerous if the sensor fell off and hit the flywheel while at high speeds.

 

[jvb]

Re: questions on magnapower + tach

an alternator as in something different from the built in charging system? there is a white wire that comes from from the ignition that runs into the power strip. it is labelled 'tachometer', and of course this is where the books says to attach to. whats the worse that happens? fry the tach? or fry the ignition? a marine tech told me it shouldnt hurt the motor in any way...