tach problem

[bkruger]

I've got a 96 Johnson 50 HP with a tach that won't work after motor rebuild. I've had the tach tested on another boat and it is fine. The needle zeros out when the ignition key is turned on, but doesn't get any farther once motor is running. The gauge appears to to be daisy-chained along with speedometer and charging gauge as far as 12v power and ground. Lights in all gauges work so I would assume that there is proper ground. I don't know what brand the tach is either. The pulse range selector is set at 6. It worked at this setting before motor rebuild so I would think it would still work after. New power pack didn't help either. It's on a 95 Grumman pontoon boat if that info is needed.<br /><br />Please help!!!

 

[Hooty]

Re: tach problem

"6" is the right selector switch setting. There should be a gray wire connected to the "S" terminal on the back of the instrument. The other end of the gray wire should be connected to a yellow rectifier wire on a terminal strip at the engine. If it's wired correctly, the rectifier might have headed south.<br /><br />c/6<br />Hooty

 

[rickdb1boat]

Re: tach problem

Is your system charging? Do you get more than 12 volts when running?