What is the green wire on a tachometer?

Green -- signal wire, usually the (-) side of the coil or the tach lead on the distributer or ignition box.

Where do you connect the tachometer?

0:051:02How to Install a Basic Tachometer Video - Pep Boys - YouTubeYouTube

How do I know what rpm my snowblower is?

Lock down the lever that engages the impeller/auger. Note/mark the starting position of the auger and the engine pulley and count how many times the engine turns over for one full revolution of the auger.

Do I need a tachometer filter?

A tachometer filter transforms poor, weak or disordered pulse signals and corrects them by stripping out leading or trailing pulse signal interference. A tach filter may be necessary when any device utilizes a vehicles engine RPM pulse signal that is of less than optimal quality for instrument analysis.

Why do my RPMs jump while idling?

Its also possible your idle air control motor is going bad. The idle air controller is simply a computer-controlled motor that controls idle. There could also be another sensor that is telling the computer to compensate, and in turn, this causes the idle to surge as it looks for the correct RPM level.