My 89 OMC 2.0 liter Seadrive is currently undercharging and I wanted to find out how to troubleshoot the stator and regulator/rectifier to determine which part needs to be replaced. After a few hours of searching and reading the Clymer manual several times, I compiled a list of things to check. Can anyone add to or correct me on these steps? I would like to run through the steps this weekend. Maybe once we get a good list going it can be posted in the FAQs. <br /><br />1. Check DC Voltage at battery terminals, when idling should be more than 13volts.<br />2. Check battery connections, change wing nuts to stainless steel lock washers/hex nuts.<br />3. Verify good battery.<br />4. Check fuse (not sure where this is).<br />5. Check that magnets are glued to the flywheel and not broken. (Use small mirror)<br />6. Check stator coils under flywheel for gooey or sticky discharge indicating possible bad stator (Use small mirror).<br />7. Check stator ohms at the 2 yellow wires disconnected from regulator, should be 0.17 +- 0.05.<br />8. Check stator yellow wire for short to ground.<br /><br />You could also check the stator output with a peak reading meter, should be about 18 volts at idle between the two yellow wires. If all of this checks and wires and connectors are good, more than likely it is the regulator/rectifier. To check the regulator recitifier perform the follwoing steps.<br /><br />1. Remove the rectifier wires from the terminal block. <br />2. 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).<br />3. Now reverse the ohm meter leads (red and black leads) and check those same wires again. <br /><br />You should get a reading in one direction, and none at all in the other direction - or if you are using a digital ohm meter you should get a reading of 0 in one direction and greater than 0 in the other.<br /><br />4. Connect the black lead of the ohm meter to the red wire. <br />5. One by one, connect the red lead of the ohm meter to the yellow, yellow/gray, and if present, the yellow/blue wire.<br />6. Reverse the leads, checking the wires again. <br /><br />Once more, you should get a reading in one direction, and none at all in the other direction - or if you are using a digital ohm meter you should get a reading of 0 in one direction and greater than 0 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. <br /><br />Most of the info here was taken from a post by clanton, another post by Joe Reeves, and from my Clymers manual.
