I have a 1979 Ebko/85hp Evinrude. I have a tach that is acting up. My question is can a tach go bad just sitting. This rig hasn't been in the water in some time. Show to be idleing about 1400 and when I go throttle up the tach goes to 6000. The tach only read from 1000 to 6000. In the past if I remember correctly the engine at full throttle was only about 4500. I completely redone the boat and had the tach out. Is it possible that I may have moved the screw in the back that adjusts the tach to this motor? How do you know where to set that screw? I can't find it in my Evinrude manual. I don't know what brand tach it is. It came with the boat, so I am supposing it is OEM. Maybe a cheap one.
<br /><br />The switch at the back should be the number of poles the stator has, not the number of cylinders on the engine.<br /><br />Then again, if it WAS the number of poles, it should read 3,4,5,6 instead of 1,2,3,4. No engine in the world has 1 pole.<br /><br />SO, I'm throroughly confused.