I'll try to keep the sordid story as short as possible..... I am running a MIVA mini ex with the Rato R420 engine. I added two computer type fans for cooling then a few days later found the battery dead (after about 25 hours of running). I recharged the battery then once running (3000+ RPM) I tested the battery again and found only 12.5v. I checked the regulator output and found 0.0volts, tested the stator for AC volts and found it ranged from 8 - 25v dependent on RPM so believed the regulator was toast. No parts found for a RATO R420 (could use a source if you know one) so purchased one meant for a B&S XR engine. Installed same and everything seemed to be working fine until I smelled "hot electric" odor, found the stator connectors to the regulator trying to melt. Removed the stator and found it burnt to a crisp so now I'm searching for stator with regulator....
I do have a stator regulator from a MTD Power 420cc motor that physically fits and the engine is running but I'm still trying to determine the proper hookup for battery charging and possible fan use (I'll test the fans first to determine amp draw).
I could use:
1. a RATO and MIVA parts outlet
2. a MTD 951-12224 Stator wiring output description - this stator and regulator has a couple more inputs/outputs than my original.
Output is the four round connectors. The loose single wire I suspect is for the coil.
Update - tested the four stator outputs and found both pairs pushing similar AC voltage. Then tested regulator output plug with engine off and found 13+ DC volts on the purple wire, orange wire was ground and nothing on the red and white wires. I'm guessing the regulator may have a capacitor holding energy. I temporarily hooked up the purple wire with DC volts to my battery feed and it immediately read battery voltage of 12.3v so I started and ran the engine for a few minutes and it provided 15+v so I may of solved my problem. Just don't want to fry another stator.
I do have a stator regulator from a MTD Power 420cc motor that physically fits and the engine is running but I'm still trying to determine the proper hookup for battery charging and possible fan use (I'll test the fans first to determine amp draw).
I could use:
1. a RATO and MIVA parts outlet
2. a MTD 951-12224 Stator wiring output description - this stator and regulator has a couple more inputs/outputs than my original.
Output is the four round connectors. The loose single wire I suspect is for the coil.
Update - tested the four stator outputs and found both pairs pushing similar AC voltage. Then tested regulator output plug with engine off and found 13+ DC volts on the purple wire, orange wire was ground and nothing on the red and white wires. I'm guessing the regulator may have a capacitor holding energy. I temporarily hooked up the purple wire with DC volts to my battery feed and it immediately read battery voltage of 12.3v so I started and ran the engine for a few minutes and it provided 15+v so I may of solved my problem. Just don't want to fry another stator.
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