This is for the Porter Cable H650IS-W-1 Contractor Generator. It has an idle/RPM control solenoid that adjusts to the load on the generator. I can see that the solenoid works because 9VDC applied to it activates it. The stop control switch seemed to test out OK with an ohmeter, and the wires leading to the solenoid are ok. So I think the problem is in the power being provided to the solenoid by the generator/alternator. Where can I find out the correct voltage and/or how to troubleshoot further?

Thanks, this generator was made in 2004 and does not have the GS-0663 ASSY BOARD CIRCUIT I as I see in the diagrams for this model out on the web now. There is a red wire coming out of the end of the alternator that connects right up to the 4 pin rocker switch/idle control stop switch, a wire that goes to ground, and then the other two pins are the two wires that go directly to the solenoid. I have yet to check the voltage at the red wire but I had checked it at the wires coming out of the switch before (assuming my testing on the switch was correct, I'd expect the measurement to be the same/low..)
Doesn't that solenoid adjust the rpm to the load on the generator so that it isn't revved up any more than it has to? The issue I was having with letting it rev where it wants - is the voltage output was up over 150 I think. Plus it is very noisy. Thanks, this generator was made in 2004 and does not have the GS-0663 ASSY BOARD CIRCUIT I as I see in the diagrams for this model out on the web now. There is a red wire coming out of the end of the alternator that connects right up to the 4 pin rocker switch/idle control stop switch, a wire that goes to ground, and then the other two pins are the two wires that go directly to the solenoid. I have yet to check the voltage at the red wire but I had checked it at the wires coming out of the switch before (assuming my testing on the switch was correct, I'd expect the measurement to be the same/low..) Doesn't that solenoid adjust the rpm to the load on the generator so that it isn't revved up any more than it has to? The issue I was having with letting it rev where it wants - is the voltage output was up over 150 I think. Plus it is very noisy.

The soleniod is for idle only. Try easy test. start generator engine and hold the throttle linkage or at carb so that you can manually govern engine speed. Hold the engine speed low and gradually open throttle, as you speed up engine you should feel the governor push against you (it should push very hard at high speed). If you do not feel this then could be problem with internal engine governor (or could be hanging up on solenoid). If you feel governor push against you then let go of throttle and adjust governor spring /adjusting tension screw or tab to correct rpm. What is correct rpm? Adjust governor spring until voltage reaches 115v or if your meter has rpm setting set to 3600 or if meter has hz setting set to 60 cycles. Do not turn on idle control during test. The soleniod is for idle only. Try easy test. start generator engine and hold the throttle linkage or at carb so that you can manually govern engine speed. Hold the engine speed low and gradually open throttle, as you speed up engine you should feel the governor push against you (it should push very hard at high speed). If you do not feel this then could be problem with internal engine governor (or could be hanging up on solenoid). If you feel governor push against you then let go of throttle and adjust governor spring /adjusting tension screw or tab to correct rpm. What is correct rpm? Adjust governor spring until voltage reaches 115v or if your meter has rpm setting set to 3600 or if meter has hz setting set to 60 cycles. Do not turn on idle control during test.