PDA

View Full Version : tach wireing


JayBrown
10-15-2013, 02:10 PM
So when I start my boat 76 s&s my tach goes to 6000 rpm at idel but sounds about 1000 rpm. It was like that all summer then when I started it would go from 1100 back to 6000 back and forth. Anyone ever had this problem as I don't like driving it with no tach:confused:

thatsmrmastercraft
10-15-2013, 02:20 PM
Are you sure tach wire is connected to the negative side of the coil? Have you looked at the wiring behind the dash? I had plenty of bad connections on my '77.

JayBrown
10-15-2013, 03:07 PM
I have looked everthing Looks ok but maybe a new wiring job is in need and which side is the negitive side?

thatsmrmastercraft
10-15-2013, 03:27 PM
I have looked everthing Looks ok but maybe a new wiring job is in need and which side is the negitive side?

The side with the - . Not trying to be a smarta$$......they are marked + and -. Crazy electronic reactions are normally the result of a high resistance connection. My '77 was doing some strange stuff and I found some corrosion in the main harness connector and the ground buss bar was broken in two pieces and making intermittent for some of the dash functions.

When I got my boat there was a lot of light corrosion the caused a handful of problems.

JayBrown
10-15-2013, 04:53 PM
Ok I will have to take a look as the only thing that works on the dash is the fuel guage