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Briggs and Stratton batery discharging.


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11-20-08, 10:11 AM   #1  
Briggs and Stratton batery discharging.

Hello everyone, I am new here and could use a little advice. I just picked up a Craftsman LT12-38 lawn tractor. I have put a new battery in it, a new ignition/ starter switch and cleaned all of the terminals on the starter solinoid and starter. The tractor starts and runs perfect the only problem is the light on the dash that says the battery is discharging is on and after mowing with it for a while and repeated starting, and blade engaging, (it has an electric clutch to engage the blades), the battery does infact discharge. In where all the wiring is there is a 5 pole relay, like a starter relay. Should I check that or where should I start? All of it looks factory, except for a wire that goes to the hot side of the starter solinoid which I will trace. I just wanted to get a few thoughts before I just start tearing into it you know. Thanks very much, Jason.

 
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11-20-08, 02:40 PM   #2  
Model number off your rider is needed in order to know what type of charging system is utilized.

I doubt that the relay has anything to do with your issue, it sounds like you may have a problem with the alternator, and or voltage regulator, failing to charge and maintain the battery.

 
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11-20-08, 02:55 PM   #3  
I forgot to put that info on my post. The model number is 917.254551, and the serial number is 1398503491. These are the numbers off of the rider itself. It is a 12 horsepower engine.

 
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11-20-08, 03:20 PM   #4  
Well, most of the time the numbers will specify certain things, but in the case of your mower, it does not.

Since you have an electric clutch, then you must have either the 9, 10, or 16 amp charging set up. My bet is the 10 amp system.

Look around your engine for a wire coming (possibly 2) should be black in color coming out and plugging into a square epoxy filled box. The box should have yellow and red wires coming out.

When you locate this post back with a description of the set up with the number and color of wires, and I will try to explain a testing procedure for you to follow. You will need a multimeter that will read AC and DC voltage.

 
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11-20-08, 03:52 PM   #5  
Ok, I found 2 epoxy filled boxes, one on the engine itself and one that was integrated into the wire harness. The one bolted to the engine is on the right hand side near the top next to the cowling. There are 3 wires, 1 red that runs back into the harness and 2 yellows that both head back in towards the flywheel. The red wire and one yellow wire are very close together where they go into the box and the other yellow is further off to one side. The box I found under the gas tank in the wire harness has 3 wires also. 1 red, 1 blue and 1 black. The black and blue wires go in to the box very close together and this time the red wire goes in away from the others as the wires did in the first box I described. Also the box in the harness, had a sticker on it that is now long gone, and also has a hole at the top as to mount it to the body somewhere. Thanks for your help. Jason.

 
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11-20-08, 03:59 PM   #6  
Rather then type this again, I just copied it from an earlier post I made. The information applies to your type of charging system.

Look on the side of your engine for an epoxy filled aluminum box with 3 wires coming out of it, this is the voltage regulator. 2 of the wires will be yellow and one red. The two yellow wires will be plugged into 2 black wires coming out from the engine, and the red will plug into the wiring harness of your equipment.

To test the Alternator output, unplug the black from the yellow wires at the regulator connector. With the engine running approximately 3600 RPM's check the "AC" voltage at the connector with the Black wires, you should have around 30 volts. If that checks out, then the alternator is good.

Unplug the red wire coming out from the regulator, and plug the alternator back into the regulator, with the engine running, test from a good ground to the red lead coming out of the regulator, you should have 13 - 14 volts "DC", if not then the regulator is bad.

Hope this helps...

 
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11-20-08, 04:51 PM   #7  
Well I checked the black leads coming out to the voltage regulator, and am not getting anything, so anyone have a ball park on what one of those might cost? Thanks.

 
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11-20-08, 04:55 PM   #8  
In "one of those" , I mean the alternator. Whoops. Thanks again.

 
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11-20-08, 06:04 PM   #9  
696458 Briggs and Stratton Alternator.

Shows to sell for around $38.00

 
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