98' Evinrude 90SPL Tach Pegged down at full throttle

kobx

Cadet
Joined
Oct 2, 2013
Messages
18
My tach has been acting funny lately. It started by jumping around, but would settle out after the engine would warm up. Now, it consistently reads a little high, and when at WOT, the needle is pegged all the way down (clockwise). The motor itself sounds fine. I've read that an erratic tach can idicate a regulator/rectifier issue. At idle, I checked the voltage with a handheld multimeter at the battery and it read 13.6V, a slight increase in the throttle position and the reading jumped up to 13.8V. Have yet to see what the voltage reads at WOT (need to bring the wife/buddy along for that one). Anyways, not sure what to make of a fully pegged tach at WOT..

For the record, this is a 98' Aquasport 175 Osprey. Also, for some reason, my fuel gauge isn't working (even with a brand new sender). It never has in the three years I've owned the boat.

I appreciate any help and/or your time.

-Ken
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
The RPM signal input is only part of the equation. You also have a power input and ground wire. Check it out. Especially since the fuel gage doesn't work either. Probably related.
 
Top