Flashing 25KW 0047253--bought kit

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boernerjj
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Hello: My 25KW Guardian sometimes will not put out power and expect for some reason when starting it does not flash the coils. I ordered and recieved from you (thanks you!) part 0H07850SR Field Boost Upfit Kit which should solve the problem from what I have read and the look of the schematic.
One problem is hooking it up, the diagram I received from you shows the AVR (Automatic Voltage Regulator?--Please confirm). So clear enough to hook up but terminals not numbered...is it the terminal that puts out 30volts.

Then disconnect wire to #4 to PCB makes sense.

BUT: after diode hook 14 to "4 tab terminal block"....which I do not have! but different configuation probably. What is the block...Is it ground? are there other wires attached to it.
I guess I can see we are providing a full time "ground" to the system?

If you could just advise me what the 4 tab terminal block really is or some wire numbers that go to it..would appreciat it...thanks
Chris
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You most likely don't have the 4 tab block as this is a generic diagram. That should be connected to the 14 wire which will usually have a few spaces on the terminal strip inside the generator. 14 circuit is 12V power when the unit is cranking or running and powers the field boost kit.

Also worth noting that dirty slip rings can cause the symptoms you're having.
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boernerjj
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Thanks for your help. And yes 14 block connect easy enough. Will check brushes, near water so gets tough weather and corrosion so good suggestion..thank you
boernerjj
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understand now....boy getting old is tough....wire was labeled #14...thanks again for your help
boernerjj
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Note to Chris> Regarding no powe output on this 25KW unit, I installed the flash kit you guys provided and understand how it should work. Unfortunatley the intermittent problem not fixed and actually runs, but no power output. engine surges on start up trying to find output I guess, but none so shuts down. I went over it today and found I have no voltage on #14, and no voltage on #4 either. following the schematic looks like it should get 12 volts from the alternator...but none. Is this a slip ring problem....sort of think so. my manual is good but provides no information or part numbers for the brushes or slip rings. Will tackle the issue, but a diagram or some sort of detail on slip ring and brushes would be helpful.
Can you advise of correct part numbers for this unit which was described in an earlier note on this thread. thanks so much...jjb
Chris
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The 14 wire will only have power when the unit is running and the power will be DC voltage (12V).

The slip rings can be measured pretty easily on that unit by removing the rear alternator cover and taking a resistance reading there, and also measuring through the brushes to see if there's a dirty slip ring problem.

The field boost kit only helps with issues relating to the PCB not supplying field boost power. If there are alternator issues or something else going on, it will only help so much.
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boernerjj
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Thanks Chris...got it; found some info on repair manual so will test further. If cleaning slip rings doesn't fix, do you stock the voltage regulator for this unit, I'll probably order one....

thx
Chris
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Yes we do have them. They're pretty easy to diagnose and verify before replacement as well :cool:
Generac tech for over 12 years. I'm here to help!
"The only source of knowledge is experience" -Albert Einstein
Looking for Generac parts? Gentek Power offers the full line of Generac replacement parts! Shop Gentek Power Generac Parts
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