12 volt system 9N Electrical Problem

[Bob Jones]

After jerking some heavier logs than I should have been doing I noticed my 12 volt alternator wasn't charging. After a look see I discovered the right tie rod arm had hit the pitail so hard that the V/R was broken so I replaced it. Then I noticed the tractor wouldn't cutoff unless I disconected the alternator pigtail and negative battery cable so I replaced the diode thinking it was shorted out. However it didn't make any difference. I'm thinking, because I haven't checked it yet that my toggle on and off switch is shorted. Does this make sense and could it be anything else? Thanks.

 

[DavidO]

Be sure that you have the diode installed in the corect direction. Since it is not working now, try reversing it.

 

[Bob Jones]

Did that already and it's not the diode. I put it in with the white ring toward the alternator. When put in the other way it does not excite the alternator and makes no difference in cutting off the tractor. Thanks.

 

[DavidO]

OK, you have the diode in correctly. Try disconnecting one side of the switch or ,if you have a vom, turn the switch off and check the resistance across it. With the switch off it should be infinity, open circuit. If not, that's your problem. I think you kinda already knew that, but just confirming it for you.

 

[Bob Jones]

Thanks Dave. Yes I'm thinking it's the switch although it seems strange that all this should happen at once and I wasn't sure if it could be something else, since electrical is not my preferred discipline. Another electrical question; What size toggle switch should I replace it with? How many amps? I plan on getting one at radio shack on the way home but not sure what size I need. 12 volts DC and what else?

 

[JMOR]

Didn't by chance get alternator #1 & #2 wires reversed it replacing things did you? Looks like that might yield your result.

 

[Bob]

The ignition circuit SHOULD draw less than 4 Amps, and the "alternator excite" is a fraction of an Amp, so at least in theory it doesn't take much of a switch, but for it to last in the real world, it's another matter. A 20 Amp switch is common.

(GETTING UP ON SOAPBOX NOW) PLEASE consider replacing the toggle switch with a simple generic keyed igntion switch. Doing so may save a kid's life someday!

 

[souNdguy]

I 2nd the vote on the #1/#2 swap. if you have #1 wired right to the charge stud, then it won't turn off once running, charging and excited.. etc.

Soundguy

 

[Bob Jones]

I'm confused about the number #1 and #2 wires being reversed since they both go on the same terminal and I only have 1 terminal on the alternator. Please explain. Thanks

 

[Bob Jones]

Now you got me wondering if the pig tail plug will go in either way then it's possible I have it turned around bass ackwards. Is this what's you mean????

 

[souNdguy]

Ok.. here's the skinny... the #2 wire needs to go to the charge stud on the back of the alternator.

The #1 wire runs thru the diode to the switched side of the key.

I don't know if the molex connector will go in bakerds or not.. I just use female spade plugs on mine cuz I'm too cheap to buy the connector...

Soundguy

 

[Bob]

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<img src = "http://ndtc3500.stellarnet.com/~blweltin/Bob/AlternatorHarness3.jpg">

 

[DavidO]

I agree with BOB. A 20 amp switch is what I would use. It should last forever. If kids might be around the tractor, use a keyswitch for safety.

 

[Bob Jones]

Thanks for all the help. I'm thinking without looking that I may have turned the pig tail around bass ackwards when I unhooked it because I didn't change any of the other wires that are wired just like the pic someone was nice enough to post. If the pig tail is on correctly then the only other fix would be the switch based on ya'll's fine support.

 

[souNdguy]

double check the wireing just in case.. you never know what tired eyes may miss.

Also.. yes.. i fthe switch is SHORTED.. that would cause it.. etc.

Soundguy