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B&S over charging

#1

P

park4019

I have a OHV, B&S engine that over charges. Model is a 287707, type 1272E1. It charges at over 16 volts, at the battery, & on a volt meter, I permanently mounted on the tractor, to monitor voltage, as I cut. Recently replaced the battery, same results. Have tried slowing engine down, so that voltage output, is 14 V, but as I cut, it increases to over 16 V. Top of the battery, is wet. Indicating a over charge situation. Alternator is a two wire, black & red. Has a diode in the system. Shouldn't complain, as the last battery is four years old, & still runs the tractor, even though a load test showed a weak battery, that's why I replaced it. All connections, are clean & tight. This has been driving me nuts, for years. Some one out there, must have a similar problem.

All help, will be greatly appreciated.
Thanks, park4019


#2

R

Rivets

This manual will show how to test your charging circuit. I'm thinking either a shorted battery or bad diode.

https://doc-0o-5o-docs.googleuserco...253/*/0B6NaqjIxWV1ySkZjTTA5TGltZEE?e=download


#3

P

park4019

This manual will show how to test your charging circuit. I'm thinking either a shorted battery or bad diode.

https://doc-0o-5o-docs.googleuserco...253/*/0B6NaqjIxWV1ySkZjTTA5TGltZEE?e=download

Thanks for the quick reply, Rivets. I have two good batteries, I'll check the diode. A manual for my particular engine, lists a voltage regulator. A Murray tractor wiring diagram, doesn't show one. I'm going to a local dealer / repair shop, with my information & see if they list a regulator & can say where its located.

Thanks again; park4019


#4

R

Rivets

From your description you have a dual circuit charging system, which uses a diode to convert AC current to DC. No voltage regulators were used on that model engine. If you are sure that both your batteries are good, then I suspect a bad diode.


#5

M

mechanic mark



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