Re: 1973 evinrude 85hp--- No spark
Although it's possible the pack is faulty, It's highly unlikely that the type pack you have on that model engine would be intermitent. Any of those packs that I've encountered that go bad, stay bad.<br /><br />I see that you are aware of the Black/Yellow wire problem and the Ignition Switch, and assume you've checked that out.<br /><br />The fact that you let the engine sit for awhile would allow the stator (under the flywheel) heat up which is normal, but if that stator is cracked and leaking a inner substance, the excessive heat would cause it to drop its AC voltage to the powerpack, resulting in no ignition. Usually one can look under the flywheel and see the substance dripping, but it's best to remove the flywheel to inspect the stator thoroughly.<br /><br />Note that the flywheel nut on that model must be torqued to exactly 105 foot pounds, otherwise the fylwheel key will shear.<br /><br />If you have a tachometer and it works, the charging system is okay (to a point) with a possible intermitent stator. If you have a tach and it doesn't work, or if you have no tach, check the rectifier as follows below.<br /><br />A bad rectifier would not be able to allow the voltage to access the battery to charge it and would cause the voltage to back up at the stator, resulting in the excessive overheating, destroying the stator.<br /><br />(Small Rectifier Test)<br /> <br />Remove the rectifier wires from the terminal block. Using a ohm meter, connect the black lead of the ohm meter to the rectifier base (ground), then one by one, connect the red lead of the ohm meter to the yellow, yellow/gray, then the red wire (some rectifiers may also have a yellow/blue wire. If so connect to that also). Now, reverse the ohm meter leads and check those same wires again. You should get a reading in one direction, and none at all in the other direction. <br /><br />Now, connect the black lead of the ohm meter to the red wire. One by one, connect the red lead of the ohm meter to the yellow, yellow/gray, and if present, the yellow/blue wire. Then reverse the leads, checking the wires again. Once more, you should get a reading in one direction and none in the other. <br /><br />Note that the reading obtained from the red rectifier wire will be lower then what is obtained from the other wires. <br /><br />Any deviation from the "Reading", "No Reading" as above indicates a faulty rectifier.
