Moving the throttle lever should have no effect on the wiring, voltages, etc UNLESS something is shorting out in the control box when that lever is advanced OR the throttle vertical arm and/or timer base is causing some portion of the engine wiring to short out.
If the stator is melting down on that 1974 85hp model, there should be obvious leakage dripping down from either the immediate forward or rear portion of the stator... dripping down on the timer base and powerhead area.
A faulty rectifier would cause voltage to back up at the stator, leading to overheating of the stator which in turn would cause the stator to melt down (as you suspect). Check the rectifier as follows AND DO NOT install another expensive rectifier until you are sure that all wiring and voltages are as they should be.
Rectifier usually fail because someone hooks up a battery backwards OR hooks up a charger backwards (Reverse Polarity).
(Small Rectifier Description & Location)
(J. Reeves)
On most 2,3,4,6 cylinder engines, the small rectifier is located on the starboard (right) side of the engine just in front of the engines electrical wiring strip. There are a few older V4 engines that have the wiring strip on the rear portion of the engine and the rectifier would be located just under that terminal strip. The smaller horsepower engines usually have the rectifier located on the starboard side of the powerhead close to the carburetor area.
The rectifier appears to be a round object approximately one inch (1") in diameter and also about one inch (1") high.
The base of it is sort of triangular in appearance and is attached to the engine with two (2) screws/bolts..... usually one screw/bolt is larger than the other. The rectifier, depending on which one your engine uses, will have either:
One Red wire, one Yellow wire, and one Yellow/Gray wire, or One Red wire, and two Yellow wires.
Note that either of the above rectifiers could have a fourth wire which would be Yellow/Blue
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(Small Rectifier Test)
(J. Reeves)
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 fourth 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.
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.
Note that the reading obtained from the red rectifier wire will be lower then what is obtained from the other wires.
Any deviation from the "Reading", "No Reading" as above indicates a faulty rectifier. Note that a rectifier will not tolerate reverse polarity. Simply touching the battery with the cables in the reverse order or hooking up a battery charger backwards will blow the diodes in the rectifier assy immediately.
