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Discussion Starter #1
I'm having trouble with a 318 B43G onan motor.The battery light had been on for a while Now after I charge the battery it will run for a while then die.Any ideas where to look (stator,voltage regulator,)last week it died and I found the problem to be the 20A fuse that goes to the key switch .Any ideas will be appreciated.Thanks Millman.
 

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A fuse only fuses the positive side of the circuit, so either your charging system is cranking out an excess of 20 amps or the circuit is going to ground. I would suspect the latter is true. Could be a wire is loose or off and the vibration knocks it against the engine block or frame. Or a frayed wire doing the same thing. If it was running when it died, I would not suspect a bad regulator or coil. Good luck and please share the cause when you find it.
 

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My guess is that your voltage regulator isn't returning enough voltage back to the battery to keep it charged. Here's the test!
 

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Check the wires at the plug that plugs into the voltage reg. The ones comming from the stator will be ==== voltage at near full throttle Then with it plugged into the rectifier/reg the wire going to the battery should show near 14 volts, I did not state the voltage comming from the stattor, It is printed in different amounts. Try 38 volts AC + - 4 volts. If you show 12 DC or more volts on the battery output side then Check Your Ignition switch. We have a box full of faulty Ignition switches.. Life is so good; Enjoy it;
 

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The Magnificent
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Before you spend a dime, check and clean all of your electrical connections. ALL OF THEM. Then check your voltages.
 

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:ditto: what D-Dogg says. Make sure your battery cables are clean and tight and check every harness plug to make sure they are not corroded. A little diaelectric grease won't hurt either :fing32:
 

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Can you define "a while"? Also when it dies what does it do when you try to restart it?

I just was sort of still am going through this. My voltage regulator shorted out and caused all sorts of weirdness. Now my machine is all back together but I'm running without the VR for now. I got through a 45 minute mowing without an electrical problem (I still have some fuel related issues from another project.)

I too was blowing the 20 amp fuse but I believe that to be bad connection problem which has since been rectified by heeding (again) the clean everything electrical advice.

Good luck
 

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Discussion Starter #10
I'm gonna check all connections today and see if that helps.If not ill break out the multimeter and see what kind of trouble I can get myself into (not real good at electical diagnosis).I probably should go pick up a shop manual for this tractor,I've never needed one till now.
 

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The Magnificent
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I'm gonna check all connections today and see if that helps.If not ill break out the multimeter and see what kind of trouble I can get myself into (not real good at electical diagnosis).I probably should go pick up a shop manual for this tractor,I've never needed one till now.
When you consider transportation to the shop and the shop labor rate, $45 for the manual on CD is a bargain.

Let us know what you find.
 

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I checked all wiring found some of them were packed with grass and dirt took them apart and blew them out used dialectric grease and put them back together.put the meter on the voltage regulator and got 36 volts at full throotle so I guess the stator is good ?.I'm thinking if the battery is not charging then it has to be the regulater.Thanks for all your help so far millman
 

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The Magnificent
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We still have not determined why the fuse blew. Your wiring inspection did not report anything out of the ordinary, so unless your regulator is shorted to ground on the output (possible), you need to keep looking.

Did you not measure the DC output of the regulator while at full throttle?

Tony, why do you have a full box of faulty ignition switches?
 

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Discussion Starter #14
D DOG is correct but I will replace the voltage regulater and see what happens I think there are two seperate problems and I want solve one and move on to the next thanx millman
 
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