My motor is an evinrude 60HP VRO from 1990, and it is running 100% OK.<br />The tach is from a Mercury outboard motor, and on the backside of the tach, are there standing<br />1. 4 cyl<br />2. 6 cyl<br />3. 8 cyl<br />4. 12 pole (this pos. is where I put it)<br /><br />The tack have no name, and there is connection for +12V, send and ground<br /><br />Last week I have installed a 2,2 K ohm resistor ( 1 watt ) between the send and ground on the backside of the tach.<br />The tach has been working 100% since I installed it apx. 2 month ago.<br />But after apx. 5-10 min run, it is going back to zero when the rpm is apx. 3500. and works okay again, if Im going down to apx. 3000 rpm.<br />But the first 5-10 min operation, it is working 100%.<br />Before I installed the 2,2K ohm resistor, the tach rpm was going up and down the whole day. But after I installed the 2,2K ohm resistor it only happens 2-5 times on a whole day.<br />Well, between ground and +12V, I read + 12,7Vdc when the motor is stopped, and 16Vac between send and ground when the motor is running at idle speed (1000 rpm).<br />When the motor is stopped I can read 12,7V on my battery, but when I start the motor I can read 16,8V at 1000rpm, and 17,6V at 2000rpm on my battery.<br />I think 16,8-17,6V is fare to high, so I have just controlled my 3-wire rectifier part.<br /><br />Yellow/gray to ground I can read infinity in one direction, and 1000Kohm in the other.<br />Yellow to ground I can read infinity in one direction, and 1300Kohm in the other.<br />Red to ground I can read read infinity in one direction, and 450Kohm in the other.<br /><br />The two wires to the stator, I can read 2 ohm.<br /><br />Is it the tach, battery, stator or rectifirer bad ????????????
