2002 mercury 150 saltwater

[raz]

I just bought a mercury 150 saltwater on a trophy dc and have been having a problem. the tach and volt meter aren't working. volt meter shouldn't be a problem but need a hand with the tach, wiring seems fine, tach seems stuck at 1k rpms.

 

[Texasmark]

Mercury tach will stay where it stopped. When you turn the key on with engine off, it will zero. Seems you have a 12v to it problem. Dirty terminal I'd look to first. Red or purple to 12v, grey to tach signal, black to ground. Measure voltage and ground at the tack stud, not the terminal on the wire attached to it. That interface could be where your problem exists.

Mark

 

[guyjg]

If the tach doesn't register properly it may be salt air corrosion. Spray a shot of WD-40 into the switches on the back of the tach and exercise them back-N-forth several times. Sand the wire connections and apply a little WD-40 to them after reconnection.