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B112_son

Starter generator bad?

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B112_son

My b112 has been doing this for a few years I just put the trickle charger on it when I'm done using but looking to get the problem fixed right. After being here for a few months I think I can tackle it.

Heres the deal. Basically the battery does not charge. Is this the starter/generator? Also the ammeter is always in the middle bouncing back just above and below 0. I have an ammeter and a s/g that was working fine in a B110 I parted out. Looking for advice where to start. Or is something completely different then these two.

By the way it has the original 12 hp Briggs. S/g never been touched. Ammeter never touched.

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BLT

First of all, the ameter doesn't really tell you squat other then amps are going either to the plus or minus side. What you really need is a voltmeter as it tells what the steady state of the battery is, how far you drew down the voltage attemping to start, how fast voltage recovers and what voltage it settles out and if the voltage holds when you turn on accesories. That means the regulator is set correctly, the battery is in good shape as it barely needs a lot of amps from the generator to maintain a stedy state.^

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maxwood

Hello I found this paragraph in the "simpletactor" main site Under "service" then electrical then starter generator troubleshooting

Maybe this will help . There is a vast amount of info over there!

Ken in Mi

Troubleshooting Charging:

1. With the engine running more than half throttle, measure the voltage at the A terminal, it should be 13 to 14.5 volts. If it is 12.5 or less, ground the F terminal, if the voltage goes up to 13 to 14.5, most likely the problem is the regulator. Other possibilities are the wire from the F terminal to the voltage regulator, and the ground on the regulator not being good. If the voltage at the A terminal is 14.5 to 17 volts when you ground the F terminal, the regulator cut-out section is probably not connecting the A terminal to the battery. If the unit is measuring 13 to 14.5 volts at the A [without an external ground applied to the F terminal] terminal, the voltage measured at the battery should be within .1 or.2 volts of the voltage measured at the A terminal, if it is the system is working correctly.

2. If the unit fails the above tests, disconnect it and remove it. Using an ohmmeter, measure the resistance between the F terminal and the A terminal. A normal reading would be 7 to 15 ohms. If it measures less than that remove the end frame and pull the armature assemble out and look at the field coil connected to the F terminal. If the insulation is scorched, or it looks as if it has been overheated it is probably shorted.

3. Inspect the brushes for wear or the leads being loose in the carbon. Look at the sides of the brushes to be sure the sides haven't worn into the indentations in the holders causing the brushes to "Hang Up".

4. With the armature out, use the ohmmeter to check from the copper commutator bars to the armature laminations or the shaft. It should show no resistance, infinity. If the reading is 0 ohms you have a shorted armature. If it is 40 or more ohms, it probably has carbon dust between the commutator bars and the frame or shaft. Blow it out all around the commutator and windings. Be warned this dust is black and messy, so do it where it won’t make a mess. Blow the field housing out at this time also. If these two tests are OK, the armature needs to be "GROWLED." This checks for shorted turns, and shorted bars in the armature. This requires a growler to do this test. Any good starter shop will have one. If the field coil needs to be replaced, one will likely need a pole shoe screw remover. This is a clamp device with a screwdriver bit on a wrench that clamps the bit in the head of the screw to remove the pole shoe that holds in the field coil. Sometimes they will come out with an impact wrench, but when the pole shoe is reinstalled one needs to be sure they it is installed perfectly straight or it will hit on the armature if the curve is not exactly parallel with the armature. At this point for most people, this would be a "take it to the shop" job.

5. Check the bushing in the end plate for looseness. If the bushing needs to be replaced one needs a blind bushing puller which costs $400.00, so this is another "shop job."

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B112_son

Thanks for all the advice. I will check the battery first. I know it takes a charge from my charger but will have it checked out.

Dumb question though, what is the regulator? Is it the black box?

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Burntime

Just a heads up from an unfortunate experience. I have had issues with a brand new battery not charging. Rewired the regulator, bought a new regulator, new brushes in the generator...only to find that the brand spankin new batter was bad. Voltage was fine, under a load, not so much!sm00

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B112_son

Thanks burn time. I'll be sure to have it checked out. Im not very good with electrical so I may have more questions. I have an extra regulator here I may just put on and see how it does.

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