Buy Yamaha Outboard Parts

Announcement

Collapse
No announcement yet.

2000 Merc/Yamaha Charging issue

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • 2000 Merc/Yamaha Charging issue

    Hello all. I’ve been reading on the forum for a long time, but this is my first post. I’ve read about every thread there is regarding Lightning Coil and R/R testing.

    2000 Mercury 90 HP 4stroke
    S/N 0G999693
    From what I understand this is just a Yamaha with Merc Lower unit?

    If the Voltage test fails when the output wire is hooked up (loaded), but all other test appear to pass, could the R/R still be bad? Or do you suspect a wiring issue? Sorry but I don’t have a manual for this engine.



    Here’s what I came up with during testing


    Voltage at Battery resting: 12.8

    Engine Idle @ battery - 12.7
    1500 RPM @ battery - 12.8

    Engine running battery disconnected, 6-9v at battery leads


    From 3 yellow wires @ R/R input
    Readings at idle:
    1-2 18v ac
    2-3 18v ac
    3-1 18v ac

    1500 RPM:
    1-2 34v ac
    2-3 34v ac
    3-1 34v ac


    Red wire from regulator at idle
    Disconnected 17v

    Red wire from regulator 1500rpm
    Fluctuates 10-15v

    Starter + lug with battery connected
    At idle 12.7
    1500i RPM 12.7

    Red wire at R/R back probed 1500 RPM 12.8


    Thanks for all your help!
    Keith

  • #2
    I would think the voltage testing should be with a peak reading meter , or with a DVA with a regular meter set to DCV
    at least that is the testing in my manual for my C40TLRX

    maybe you should find a manual for your motor

    Comment


    • #3
      The stator output is checked with AC Volts and the R/R is checked with DC Volts.

      The the yellow wires from the lightning coil all tested out at the same around .4ohms if I recall.

      I was able to download the manual today. No where I’ve seen really states if the R/R can pass an unloaded test but fail a loaded test. Is this typical?

      Only test I did not run is a diode test on the R/R.

      Comment


      • #4
        Last edited by xMacG_18; 06-11-2024, 08:40 PM.

        Comment


        • #5
          Last edited by xMacG_18; 06-11-2024, 08:39 PM.

          Comment


          • #6
            Last edited by xMacG_18; 06-11-2024, 08:39 PM.

            Comment


            • #7
              looks like you found a problem

              Comment

              Working...
              X