Tacho on old merc500????

[pmoreel]

I have a tacho in my garage that was supossed to be mented for a car. There are 3 wires coming out wich are ground, 12v and signal.

Is it possible to hook this tacho on to my merc 500 thunderbolt?

If it is possible how do i fix this?

And what is the right rpm for my motor in neutral and in gear? (hanging in the water)

Greetings, Patrick

 

[Chris1956]

Re: Tacho on old merc500????

Patrick, I am sceptical that the tach will work on the Merc. It was meant for a single coil, battery driven, conventional points/condenser. You might try hooking it to one of the yellow/red stator wires and see if the reading makes sense. Your motor might convince the tach that it is a 6 cylinder 4 cycle motor, or it might not.

 

[pmoreel]

Re: Tacho on old merc500????

The tach was originally designed for 4, 6 or cylinder motors. I can put setting on either one of it.

Is this better?

What is the right rpm for this motor in gear and in neutral?

And last but not least what is the max rpm for this motor?

 

[Chris1956]

Re: Tacho on old merc500????

I would try the 6 cylinder setting. Idle speed should be 800-1000RPM. Try to find a setting that gives that RPM at idle.