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September 12, 2025 at 10:35 am
#299835

Ok guys. I’m going to do an evaluation on the 1959 Evinrude 18hp.
Shifter cable or clutch dog troubleshooting
Compression testing
I own a Merc-O-Tronic (still trying to figure it all out). So coils and condensors will be tested
It’s hard to start after sitting for a week, however it will fire up in 2 pulls after sitting for only a day. So fuel system will be checked as well.
Thanks to everyone for chiming in. I’m more motivated to get the ole Evinrude guessed up.
Below is a list to setting up your Merc O Tronic. I have learned to do this every time before I go to use it. Mine is an 88 so yours may have more or less knobs but the procedures should be the same.
Condenser testing. Connect the small black wire to the body of the condenser and the small red wire to the condenser wire. When testing for ” Condenser Leakage and Short” or “Condenser Capacity” press the red button for a minimum of 15 seconds, and read the corresponding scale.
Coil testing. Connect the small black wire to the ground wire of the coil and the small red wire to the wire that goes to the points. Connect the large (red) wire to the spark plug wire. With the selector switch in the “off” position – turn the Low – High knob to low. Turn the selector switch to position (#1) Coil Power Test. Begin turning the Low – High knob to high until you just get arcing in the window. That point on the #1 scale is the amperage reading for that coil. Now as we don’t have the amperage readings for most coils we use, a real high reading may indicate a broken wire in the secondary. No arc in the window is an open secondary. A test I like to do, with the coil mounded, small black wire connected to the magneto plate, small red wire connected to the wire that goes to the points “but not connected to the points”, spark plug wire connected, turn the Low – High knob up all the way. This will expose any leaks.

A "Boathouse Repair" is one thats done without having tools or the skills to do it properly.