Chinese 1E40QMB Regulator/Rectifier Wiring Issues
May 14, 2011 14:20:40 GMT -5
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Post by 90GTVert on May 14, 2011 14:20:40 GMT -5
Myself, and it seems many others, have had a lot of trouble finding replacement regulator/rectifier units for Chinese Minarelli/1E40QMB powered scooters that actually work. There are replacements out there that will plug right in and work without issue, but they are hard to come by. All of the plug 'n' play units that I have found are marked as shown in the pic below.
I used to be able to get those units from Vento directly, but since they have gone out of business, I'm unaware of a reliable source for that exact regulator/rectifier. I've tried units from a few sellers recently, with no luck. Bulbs keep blowing and the battery isn't charging when swapping in the replacements I have that were specified for these engines. If you aren't sure if your scooter is charging, CLICK HERE.
190mech brought it to my attention that the connections could be checked and swapped around in order to successfully use generic 1E40QMB replacements. Of course I investigated further.
I used a multimeter set to check diodes, as described HERE, to see if I could find the difference in a stock rectifier/regulator that works as-is and the replacement units. What I found that the highest reading was obtained with the positive probe on the same terminal, but the negative probe had to be on different terminals for each type of rectifier. The stock plug 'n' play unit had to have the red probe on the top right terminal, while the replacements needed the probe on the top left terminal when looking at it as shown in the diagram lower on the page.
This result led me to believe that the top two terminals needed to be swapped. Before changing my wiring, I used some jumpers that I had made up to be sure this was the correct change.
I was correct, so I swapped the terminals around as shown in the diagram below.
If you look inside each cutout below, you should see a small tab at the bottom. If you push that tab upwards, the terminal should be able to pull out. Remove both top terminals and swap them with each other. They'll slide back in easily. Just make sure they are secure. If not, make sure the tab that you had to compress is bent out as it was before you removed the terminal.
So there you have it. With a small amount of work you should be able to use most replacement regulator/rectifiers sold for 1E40QMB engines.
I used to be able to get those units from Vento directly, but since they have gone out of business, I'm unaware of a reliable source for that exact regulator/rectifier. I've tried units from a few sellers recently, with no luck. Bulbs keep blowing and the battery isn't charging when swapping in the replacements I have that were specified for these engines. If you aren't sure if your scooter is charging, CLICK HERE.
190mech brought it to my attention that the connections could be checked and swapped around in order to successfully use generic 1E40QMB replacements. Of course I investigated further.
I used a multimeter set to check diodes, as described HERE, to see if I could find the difference in a stock rectifier/regulator that works as-is and the replacement units. What I found that the highest reading was obtained with the positive probe on the same terminal, but the negative probe had to be on different terminals for each type of rectifier. The stock plug 'n' play unit had to have the red probe on the top right terminal, while the replacements needed the probe on the top left terminal when looking at it as shown in the diagram lower on the page.
This result led me to believe that the top two terminals needed to be swapped. Before changing my wiring, I used some jumpers that I had made up to be sure this was the correct change.
I was correct, so I swapped the terminals around as shown in the diagram below.
If you look inside each cutout below, you should see a small tab at the bottom. If you push that tab upwards, the terminal should be able to pull out. Remove both top terminals and swap them with each other. They'll slide back in easily. Just make sure they are secure. If not, make sure the tab that you had to compress is bent out as it was before you removed the terminal.
So there you have it. With a small amount of work you should be able to use most replacement regulator/rectifiers sold for 1E40QMB engines.