tecumseh 17.5 charging system

JAYJAY

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The diode lets the power pass one way and not the other. Basically the single diode acts like a half wave rectifier. it lets one half of the AC alternating current pass but not the other. It is not a true DC current more of a DC pulse. So if you are getting 27 volts AC then you should get 13.5 pulse DC through the diode for battery charging.

ok i will try that tonight thanks alot for the help you guys are great!!
 

EngineMan

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im doing the wiring its for a snowblower projet for my atv. need to charge the battery from the red wire that coming from the magneto of the engine. i have 27 volts coming out of the motor and i need 12 volts for the battery and i have not voltage regulator or rectifier.

You mean (alternator/stator) not "magneto"
 

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JAYJAY

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Just to let you guys know it did work with the diode have another question when I start the engine it run rough and black smoke is coming out for a few second and then it runs perfect would it be with the carb solenoid not shutting the gas with the kill swtich
 

ILENGINE

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No I would be thinking sticking choke. The solenoid on the carb just is to help prevent the bang after shutoff. It shuts off the fuel jet to prevent fuel from being drawn in after the key is shut off. It doesn't control fuel into the carb, nor will it prevent the carb from flooding.
 

JAYJAY

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No I would be thinking sticking choke. The solenoid on the carb just is to help prevent the bang after shutoff. It shuts off the fuel jet to prevent fuel from being drawn in after the key is shut off. It doesn't control fuel into the carb, nor will it prevent the carb from flooding.

well after the engine is warm i dont need the choke to start it the throttle is way down on idle on it does the samething if it was on the choke.
 

Fred1941

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thats what i taught so i bought a 6 amps 100 voltgs diode. but my question is will that diode work or i need a special diode for that motor
I just transplanted same Tecumseh engine into a Husky tractor (ex B&S). Turns out the charging circuit was dead but there is an AC output there as well and it was functional. I had no idea of what amperage was involved but I had a few 3 amp diodes in my tool box so in they went (3 in parallel). Anode (+) to the Alternator and Cathode (-) to the machine. First, I made sure the battery was charged so as not to overload the diodes. Hooked up volt meter to the battery and started it up. Got a nice charging boost in voltage. Put an AC ammeter on the diodes and saw 3 amps. Next I engaged the clutch and saw little change in amps. Spent an hour or so mowing and the battery voltage held up. So I'm calling it good.
 
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