410c not charging

mj12687 · Jul 30, 2015

hello all. new here and new to tractors as well. i have a 410c backhoe that is not charging properly.the product id number of the tractor is TD410cF746282. the alternator is brand new. i replaced it yesterday and its still not charging. the wiring going to the alt is a little screwy looks like a previous owner has tried to repair it. does anyone have access to a wiring diagram for this model or any info to point me in the right direction. the alt is putting out only 3;4 volts which makes me think its not being grounded properly or there is a regulator issue but im not sure. any help is greatly appreciated thank you all

Tx Jim · Jul 30, 2015

Does exciter wire have 12 volts?

mj12687 · Jul 30, 2015

no when the tractor is running i have about 3-4 volts off the b+ wire on the back of the alt. there are 3 more wires that go to the alt. the alt that came off the machine i was told by john deere wasnt the correct one. it appears some one modified the wiring to make it work. the alt i put on is the correct one according to the local deere dealer. im trying to put it all back to the way its supposed to be. its no help that al the wires ahve been painted yellow.

Zebrafive · Jul 30, 2015

If you look at the rear of the alternator there will be section kind of "C" shaped with three terminals. Starting at the lower terminal (most counterclockwise), that terminal will be empty. Next up will have two wires. One will go to starter solenoid "B" (battery) terminal. The other will go to a CB (circuit breaker) make sure the CB is good, then from CB to key switch B terminal. Next up will go to alternator dash light then to VR (voltage regulator) This covers the "C" shaped section.

Next (going clockwise from the "C" shaped section of three terminals) will be a rectangular opening with a male blade for a terminal (might be marked F or field) it goes to the VR

Next, going clockwise, is a screw stud terminal. This is ground it goes to the VR.
Next, going clockwise, also a screw stud terminal, another ground, not used.

Those are the five wires to the alternator.

From the key switch should be two wires (from separate terminals, marked A) one will go to the VR. The other will go to the alternator light (NOT the same side of the bulb as the wires from the alternator).

The alternator light does NOT have a ground. One wire is from the key switch. The other to the alternator. When the key is turn to ON the bulb should light. This voltage goes to the alternator "telling it to start charging" When the alternator starts to charge it will send voltage back towards the alternator light . This voltage will be higher than battery voltage. The two voltages will cancel each other and the light will go out.

If the light is burnt out the system will not receive voltage and will not charge.

EDIT: If your alternator is not like this it might be I am thinking of 401, instead of 410

mj12687 · Jul 30, 2015

thank you for the response i think you may have it figured out. i just got off the phone with john deere. there are only 4 wires going to my alt and according to them the alt has a internal regulator. there is a B+ wire and 3 small wires i believe the alt i got from my parts store is incorrect. im trying to have them locate another one for me the part number i got from deere is SE501368 which when looked up is an internal regulator and external fan. the alt i got loks to be what youve described as having an external VR. does this sound right has someone changed this over from having a external VR to having an internal?