Tach not working

"1990 Johnson GT-150, tach was

"1990 Johnson GT-150, tach was replaced, all wires were checked, it has power going to the igniton terminal on the back of the tach

Where is the Tach sending unit located,"

"for info, the tach has 4 conn

"for info, the tach has 4 connections on the back
one says ign and has a pink wire going to it, it has power

one terminal has the ground, which is a black wire that connects in with the other gauges, the other gauges are working so I'm guessing it is grounded

one wire, blue which is for the back light it works

last connection on the back of the tach says sending unit, it is a gray wire and I have traced it back to the motor and has no cuts or nicks so the wire is good, the gray wire goes to a plug in the controller mounted beside the drivers seat, right below the key switch, then comes out and goes to the motor

I am pretty sure my sending unit is bad, help me locate it"

"The tach pulses comes from th

"The tach pulses comes from the regulator.
Check the charging. If that is ok, take the tack out of the dashboard, hook it up with pos and neg and one wire from grey at regulator to puls at tach. If still not working try to wigle a lile on the adjustment screw at the back. It should normally be at 6.
PS: Did You get the correct type of tack?"

"I am new to this boat, so bea

"I am new to this boat, so bear with me

where is the regulator located?
check the charging, charging of what the regulator or the battery?

are you talking about a battery + and - and then a wire from the regulator to the sending unit terminal, when I find the regulator I will try that

adjustment screw is set on 6, and the tach was a direct replacement from the Ranger dealership, It is a different brand but looks identical"

"On top of the block behind th

"On top of the block behind the flywheel is the regulator.
1: Take a volt meter and measure the charge voltage, ought to be about 14+Volts at 3000 rpm. You may masure at the battery or anywhere in the system, the pos and neg at the tack , (wires connected) is one place!
If voltage is ok, regulator is ok and gives signal!
If voltage just above 12Volts, regulator is defective and must be changed.
If voltage ok, hook 12 volts pos and neg to the loose tack and follow the grey wire going from the tack, down to the stb side of the engine and check for signal. If tach works, test the plug in the remote.
To make a rough test to check if You have any signal to the tach, take pos from volt meeter to the grey wire at the tach and neg to ground. (Take the grey off the tach first) If You have any signal, Your 'new' tack may be defective!"

"alright at lunch I found the

"alright at lunch I found the regulator, and checked the battery for 14+ volts and the highest it would read was 12.18 volts from the battery while the motor was running

defective regulator

also checked the new tach and the old tach, they are both good with the grey wire off and the red terminal of the volt meter on it and the black terminal grounded the volt meter did not show any thing

thanks for the help"

"Just to be sure, do an ohm te

"Just to be sure, do an ohm test between the yellow wires going to the regulater from stator (under flywheel). Measure between each of the Yellow =resistance. Meassure between each of the Yeallow and ground = no reading, open circuit.
If contact to ground betwen any of the yellow and ground, stator defective."