Welcome Guest - Sign Up today
Welcome Guest - Sign Up today


No announcement yet.

98 Merc 40 HP, 2 stroke, 3 cylinder, SN : 74587X

  • Filter
  • Time
  • Show
Clear All
new posts

  • 98 Merc 40 HP, 2 stroke, 3 cylinder, SN : 74587X

    Hello, my first post; I recently bought a 1998 Lowe Jon Boat with a 98 Merc (40 hp, 2 stroke, 3 cylinder, SN 74587X).

    I'm in the process of discovery and getting the motor updated with all the essential services.

    Wanting to do as much of the work for myself as possible; matching part numbers with my motor seems to be very challenging....I absolutley hate ordering the wrong parts.

    Finding a supporting vendor is #2 on my list.

    The motor runs pretty good, I have a maintenance book & fuel pump kit on order, but I cannot find the proper water impellar kit or spark plug wires. I heard the overheat alarm beep yesterday when I was picking up my duck decoys in a murky slough.... The plug wires look original.

    Any info would be much appreciated.


  • #2
    Mercury-Mercruiser 47-8508910 IMPELLER

    Mercury-Mercruiser 84-821945A61 CABLE ASSEMBLY Hi Tension

    mercruiserparts . com/40-3-cyl--0g590000-thru-0g760299

    Medford, WI


    • #3
      Thanks Roscoe...

      So I have just finished catching up on most of the services on the motor..

      Fuel Filters
      Fuel Pump Kit
      Spark Plugs & Wires
      Thermostat Kit
      Water Pump Kit
      Grease fittings
      Compression Test (all even at 100 psi)
      Gear Oil

      Upon testing at idle, the temp alarm was sounding off & water was gushing up through the shifting linkage hole.

      After going back to the book, I realized that I failed to set the plastic water coupler onto the pump for the install. I had set the coupler onto the copper pipe.

      Corrected my mistake and the motor runs perfectly!

      Motor is in great shape!


      • #4
        Sign up today

        happy boating
        Medford, WI