Tach problems

[mrtim1]

I got a 85 90hp johnson that when it reaches<br />4000 - 4100 the tach falls to 0, and when I throtle back to that point it comes back up to 4000.The boat still runs great while this happens and it is still charging.I also installed a new tach and it still does it. Could it be a bad diode in the regulator assm.I could use any hints before I drop $300 on a new reg/rec assm.<br />IP

 

[clanton]

Re: Tach problems

If system is charging about 14 volts with hot battery, regulator is probley bad, but i would check the stator to.

 

[mrtim1]

Re: Tach problems

Thanks but I did a ohms reading and it was fine and also tested amps at wot and was getting over 9 amps ( 10 amp system )but I just heard from a buddy that on some of these engines you need to put a 2000 ohm resister between the ground and send studs on the back of the tach.I just back from radio shack and going to the water tonight.