Hello all,

I have a Tao Tao quad with the 150cc GY6 engine. From the factory, the rectifier assembly is the 4-pin type with no fins on the side. I don't know anything about the stator, however. The problem is the regulated voltage leaving the stock rectifier - it's only about 13.0 volts, even with the engine revving. From what I have read on this forum, this appears to be low. I have replaced the regulator with no change in operation. The wiring harness feeding the rectifier includes a +bat wire (red), a gnd wire (green), and two stator wires (yellow). Both the yellow wires put out AC.

Here is my real question - could this be the wrong regulator for this engine? I've done some ohmic measurements of the stock rectifier and I can't even see a semblance of a diode bridge inside. I would expect to see the diode bridge at the yellow wire terminals, but I don't.

I see there is another style 4-pin unit that has fins on the sides and there is a schematic floating around on the web for it. Could it be that this is the one that should be used with this engine? The unit without the side fins is touted as the one to use with the 110cc engine, not the 150cc one.

Your thoughts/suggestions are appreciated.

Doug

 

Certainly you should see the diodes from each yellow wire to ground (2 out of the four diodes of the bridge rectifier).

Set you meter to measure current on the 10 amp scale. Remove the fuse and insert the meter in its place. Start up the quad and turn on the headlights. At idle the stator won't be able to keep up and you will see current coming out of the battery. Rev the engine up. With increasing engine speed the current should diminish to zero, change polarity and go back up. The reversing polarity point is where the stator/regulator is able to run the headlights and have enough gusto left over to feed some charging current back into the battery. And of course if you turn off the headlight the stator will be able to charge at low speeds as well.

GY6 engine stators are different from most 110cc machines. Hence you need to be sure to have the matching regulator. Whether or not there exists GY6 regulator that look like the 110cc regulators is something I don't know.

WHen measuring your stator output voltages (yellow wires) be sure to measure them with the regulator disconnected, and measure from yellow wire to yellow wire (not from each yellow wire to ground). I'm at work now (I have no internet access at home at the moment - ISP problems) so I don't have the numbers in front of me. But think you should have 9 volts AC betweeen the yellow wires cranking, with 22 or so volts at idle.