Tach wiring for a '67 Thunderbolt 500?

[zonaman]

I've got a tachometer I'd like to wire up tp my 1967 Mercury Thunderbolt 500. The starter battery for engine is separate from the one I use to run accessories (i.e. instrument lights). How do I wire this up? I'm not familiar (yet) with this ignition system other than to note it doens't seem to use points or a coil. Below is the wiring diagram that came with the tach.

Thanks for your help.

 

[mmf]

Re: Tach wiring for a '67 Thunderbolt 500?

I think your motor has a magneto and you cannot wire it up per the instructions you have. What is your serial number of the motor? If it is a magneto, the points in the magneto did not run on battery ignition, they break and make the magneto coil and it is a totally isolated, self supplied voltage, if you hook anything up to the terminal on the magneto, you will fry your ignition.

 

[zonaman]

Re: Tach wiring for a '67 Thunderbolt 500?

I think your motor has a magneto and you cannot wire it up per the instructions you have. What is your serial number of the motor? If it is a magneto, the points in the magneto did not run on battery ignition, they break and make the magneto coil and it is a totally isolated, self supplied voltage, if you hook anything up to the terminal on the magneto, you will fry your ignition.

ser# 2214875- That's a type II (as per Seloc) isn't it?

 

[carholme]

Re: Tach wiring for a '67 Thunderbolt 500?

Here is the parts list for s/ns 2097445 thru 2305100

http://www.crowleymarine.com/mercury-outboard/1110.cfm

Gerry

 

[merc850]

Re: Tach wiring for a '67 Thunderbolt 500?

That motor has Thunderbolt electronic ignition and your best bet is to get an alternator driven marine tach from a dealer or this website.