How do I connect a tachometer?

[MN Driver]

I started my generator up as I normally do about 4 times a year or so and it still runs great as it always has(it is a mid-80's model).

I tested the output voltage while it was powering a vacuum cleaner as the normal test load and the voltage read 145 volts. When picking up the manual it said if the voltage is off that voltage is a function of engine speed and to connect a tachometer to set the proper speed 25% or higher load(1500 of 3000 watts). The tachometer I have here has a black and a red wire. Do I simply connect black to ground and red to the plug? If I don't connect it to the plug then where do I connect it to?

Thanks

 

[The_Jeff]

Where it's a one-lunger you'll have a hard time using a tach that's intended for 4-6-8 cylinders. The fewer sparks per minute would only register a couple/few hundred RPM on the scale.

You don't connect to the plug but rather the negative terminal of the coil. Not knowing magnetos very well I'd bet that's the wire that gets grounded by the ignition switch to shut the thing down. i.e. not a thick high tension spark plug wire but one of the normally insulated thin wires.

There should be a governor on this thing which I'd check for gungked-upedness.

 

[WDP]

Get yourself a voltmeter with the Hertz option. Go for 60 cycles with moderate load, the voltage can and will vary by the load applied. Generators are supposed to make 60 cycle power, voltage only has to be "close", higher is better for starting the surge motors on freezers, refrigs, stuff like that.

WDP

 

[MN Driver]

Thanks for the replies. The tach I have is for a 4-cyl but it is supposed to run at 3600 rpm according to the manual, so 3600/4=900 rpm. The hertz measurement sounds like what I should go with but the manual didn't seem to mention anything other than using a voltmeter to adjust the governor to 3600rpm.

The generator was bought for the purpose of running the furnace, fridge, freezer, and lights as needed(not everything simultanously). We have an plug in the garage with a 12 foot cord to connect to the generator when it's needed. The line goes to the basement with a 4 circuit transfer switch.

The governor seems to move freely and there is much less hesitance to a motor load(freezer, fridge, furnace) than what I have seen with other generators, I've kept it clean and oiled and it seems fine.