tach ? (4.3 mercruiser)

Discussion in 'Boats and Motors' started by boss302, Jun 20, 2008.

  1. I have a ? for thise more experienced than myself. My father-in-laws boat has a 4.3l mercruiser i/o and the tach has up and quit working. What/where should I investigate? I've already looked up under the dash and the wires all seem nice and tight. Boat is only about 4 years old.
  2. freyedknot

    freyedknot useless poster

    i am pretty sure the wires run to the coil.

  3. You might check behind the tach itself. There is a switch on it for 6 or 8 cylinder. It might be stuck in-between. Good luck
  4. Check the wire from the coil to the tach.check to see if power is going to the tach with a volt meter with the Ignition turned on.be careful not to short anything.If power is going to the tach it is probibly bad.
  5. Any idea how to remove the gauge from the dash? Boat is a Trophy. The coil wires are tight and connections look good, but I can't get to the gauge from behind too well. Looks like there are a possibl coupple screws holding the gauge in place from behind but I didn't want to start a big project as we were getting ready to head out on the water.
  6. pull the connectors some times they corrode and don't make good contact ,,they may be tight but not making contact