Tachometer testing

[JLBJR]

Is there any way to test a tachometer? I have replaced the alternator and it had a tach wire out the rear. I found the send wire from the tach in the engine wiring harness by doing a continuity test and connected them together. The needle does not move. BTW, the tach, which has never been connected, is sitting at about 700RPM, not zero. My thought is that the tach is bad, but hate to simply swap parts only to find out it was something else. I have read other tach posts, but none I have found refer to tachometer testing.

Thanks

[harbin2]

Yea, testing is the way to go. My fuel gauge reads near half when the ignition switch is off and fairly accurately when it is on.
If your engine has spark plugs you can get a simple auto tack tester. They are cheap. If it's diesel, there is an piece of electronic test equipment that will do the same thing but without a sync wire - try google.
harbin2

[timebandit]

Inside the alt. is a pulser coil that can be checked by conecting the wires to a analog meter set to low voltage.

if the alt. is sending you should see the needle just bounce at cranking speeds.

If the needle moves when you check it and then you hook up the tack and the tack does not work then you need a need a new tach.

[JLBJR]

Excellent advise. I have my multimeter and I am ready to go check for a pulse!

Thanks.