john deere 4110 not charging

[collin1450]

i have a john deere lv4110. serial number lv4110g112091. its not charging the battery. just had the alternator rebuilt. its the 55amp alternator not the skinny smaller alternator. the battery light is not coming on, bulb is good. iv swapped relays and made sure all fuses are good. im down to it being the voltage regulator but wanted to ask first, am i missing anything. thank you guys

 

[beenthere]

Welcome to TBN
Do you have the service tech manual for the 4110?

 

[al3]

Have you check outputs of alternator and voltage regulator with a meter? Like below has schematics, a few select test voltages. Click on the "Electrical Diag and Ops" illustration.

4110 charging issue

www.greentractortalk.com

 

[collin1450]

Have you check outputs of alternator and voltage regulator with a meter? Like below has schematics, a few select test voltages. Click on the "Electrical Diag and Ops" illustration.

4110 charging issue

www.greentractortalk.com

i read that post this morning. my diodes are there and plugged in. i ohmed out the diodes with my meter and they seem fine. both beep. battery connections are good. no power to the battery bulb in the dash. i believe thats connected to the voltage regulator

 

[LittleBill21]

am i missing something? the main lug on the alternator doesn't look connected to anything

 

[collin1450]

that

am i missing something? the main lug on the alternator doesn't look connected to anything

thats how it was when i got it. power probe says its ground not voltage

 

[LittleBill21]

that

thats how it was when i got it. power probe says its ground not voltage

look at this. interesting design

4110 charging issue

www.greentractortalk.com

 

[collin1450]

am i missing something? the main lug on the alternator doesn't look connected to anything

i work on alot of tractors its not uncommon for the lug not to be used.

 

[collin1450]

looks to me like this is the European design with the 55amp alternator not the 20 amp skinny alternator

 

[LittleBill21]

i work on alot of tractors its not uncommon for the lug not to be used.

so they are pushing 55 amps through the voltage regular wiring? that looks to be 10-12 guage at most. I have not worked with external regulator's very often.

 

[collin1450]

im not sure. still looking through the diagrams trying to figure out whats going on. for sure whatever reason the battery light on the dash is not getting power is related to the alt not charging. as far as the diagrams the light is connected to the voltage regulator/ rectifier. this dam toy size tractor is complicated haha

 

[al3]

Here's the Theory of Ops and Charging circuit description. You've stated you checked voltages. Suppose to have 50VAC unregulated out of the alternator and 12.4 to 13.8 Volts DC regulated . What you got?

 

[LittleBill21]

Here's the Theory of Ops and Charging circuit description. You've stated you checked voltages. Suppose to have 50VAC unregulated out of the alternator and 12.4 to 13.8 Volts DC regulated . What you got?View attachment 808484
View attachment 808485

really appreciate this @al3 enjoyed the theory of operation as well

 

[collin1450]

so update. replaced regulator still no charge. found if i unplug the back of the alternator the battery light turns on, plug it in the battery light is off. with alternator unplugged the two wires going to the alternator have 12v but with it plugged in one wire has .5 the other has 4v. those wires come from the regulator. its hard to tell but looking at diagrams its looks like maybe this machine is suppose to have the smaller 20 amp alternator. previous owner said he never could get it to charge, i wonder if someone swapped in the 55 amp? any ideas? the regulator i have when you look for new ones it does say 20 amp on it.

 

[collin1450]

the more i look at the diagrams its making me think this setup is for the 20 amp alt not the 55amp

 

[ruffdog]

I know for my x744 they offered a kit to upgrade to the better alternator.

 

[ruffdog]

The upgrade kit for my x744 comes with the alternator but also a jumper to the solenoid and wires to bypass the regulator. The new alternator must have an internal regulator. In your case, I wonder if someone just bought the better alternator but didn't follow through with the rest of the install?????

John Deere 40 AMP Alternator Upgrade Kit - BM20990

 

[collin1450]

the 55 amp is a completely different wiring diagram its internally regulated. while the smaller alternators have the external

 

[Cdash]

I just went through issues with my 4100. From my reading, the larger alternator is internally regulated. I suspect on your tractor it is trying to regulate an already regulated power source and not doing well. Probably because the 20 amp alternator is kicking out near 30V to 50V AC to the regulator and the alternator on your tractor is kicking out 14V DC into the regulator. So the regulator probably "thinks" the alternator isn't working. I would swap a 20 amp alternator in and see what it does.