Have a John Deere 310D backhoe TO310DG 782087 with charging issues. I'm looking for the locaton of the voltage regulator and possibly a copy of the electrical diagram for the charging system. I have the red eng/volts light on constantly. When it's on it's either not charging the battery or the charge is 14.65 (I assume over charge). I've had the alternator rebuilt, changed the ALT relay and the key switch. It has blown the 7.5 amp MFWD/ALT fuse twice. I've looked everywhere for the voltage regulator. Doesn't appear to be in the alternator, but I sure can't find it. Thanks for any help or advice.
I've never seen Deere use an external regulator on a 310D. I looked at the parts pages, and it shows alternator with internal regulator. If that's the case, don't know what else to tell you, it's an alternator problem. :beatsme
Thanks so much for looking that up. Do you have any idea if 14.6 volts is too much for the output? Seems like a charge at that level would have the battery boiling? I'm not sure of the Eng/Volt red light only only indicates low voltage. Could it also indicate high voltage? The shop that rebuilt the alternator is very good. Could they have made a mistake? Sure, however I took it off a second time and they looked at it again and found no problems. I really appreciate you input. Any chance you could post the charging system wiring diagram. I think that's the last piece of my puzzle.
14.6 is borderline what you want to see, and for sure too high if the battery is fully charged, that's where the regulator is supposed to slack off on the charge. I'm not saying the alternator shop made a mistake, but anything is possible. Take it back to them, tell them exactly what it's doing, and remind them "yes, I know you (the shop tech) don't know my machine wiring, that's not why I'm here". After they put it on their bench and test it, have them explain to you what each post/terminal connection is for and what it's supposed to do. Once you've established for certain the alternator is working properly, then you can move on to problems with machine. I don't have access to wiring diagrams, but we'll figure out what's going on one way or another.
My diagram is in the tool shop tonight, however the owner of the alternator shop drew me a diagram of port 1/2/3. Something like B+, ignition and 1/2 voltage (7 volts when the battery is charging). He even gave me an extra three pronged connector for troubleshooting. I may have to see if I can get him to come out an look at it. I really need an electrical diagram for him/me to look at. I'm sure there is a John Deere shop somewhere with a good electrical troubleshooter. Just haven't found him/her locally!
IM There are some very knowledgable folk here, some are electrical experts. Answering these Q. may give them some more insight into your problem. Is your voltmeter verified to be accurate? (Measure your truck/car voltage.) Where are you measuring the 14.65? Across the battery terminals? Across the battery connectors? Shut the engine off and measure battery Voltage-- Measure battery voltage 15 minutes after shutdown. Does machine crank very briskly? With machine off , burn the lights for about 30 min to discharge the battery some. Then crank and promptly measure battery voltage-- Have you tried another battery? These are some test that give clues as to where the problem might be. Just from your post, I would try another battery. Good luck
Check the voltmeter against another voltmeter. Seems to be accurate. I checked the votage across the battery conectors. With the engine off, it measurers 12.64 volts. Cranks very briskly. The batteries are two six volt batteries connected together. Seem to be fine.
310D battery voltage I have a 1992 310D with two 12V 1000 CCA batteries. The alternator was bad so I installed a new from UAP alternator. I get 14.6 volts across the battery terminals with engine running. I don't remember if it was 14.62 or 14.64. It was a couple months ago but it was 14.6 something. I don't think the voltage will increase or decrease if the battery is 80% charged or 100% charged but the alternator's amperage output will decrease as the battery approaches full charge. With engine running the voltage must be at least 14 volts, preferably more for your battery to stay healthy. I think your alternator is good.
Thanks! Glad to know 14.6 volts is normal. I have two six volt batteries wired in series. I'll keep looking.
Man, lots of deep thought in this thread. Davidd so right, think of everything, just like checking your test lite bulb on a good know battery before doing any trouble shooting. I had lighting problems today on one of our trailers, bad ground. Always remember a bad ground is equally problematic. My only thought here, if I were to ever replace batteries would it be better to use two 12 volts in parallel?
Everyone looks at the battery terminals and then move on. Hold on, there is more to check. Check the copper wire that is connected to the battery connecter. Swollen insulation is a give away. Then the two battery wires have another end. The ground is usually connected to the block or frame. Check there for corrosion and rust. Same for the hot wire that goes usually to the starter area. They seem so simple and innocent but those are the kind ya gotta watch.
Connections and the cables look really good. I protected them with some red spray on product when I replaced the batteries a few years ago. I will check the ground through. Good idea. Is there any "electrical" check to test for a good ground with my multimeter?
310d charging issue my 310d has two 12-volt batteries in parrelel
Ran the 310D for two hours today. Started with "ENG/ALT/VOLTS" light on and no tachometer indication. Also, parking brake light inop (parking brake works fine). Checked charging: 14.6 volts. Turned ignition switch quickly on/off. eng/alt/volts light went out. Checked voltage, charging at 14.6 volts. No tach or PB light. Used backhoe for 2 hours. Still charging. Now 14.35 volts. Ok, must be a single circuit which controls the tach, alt light and parking brake light (parking brake works fine).
If your voltage is over 14 volts it is obvious the alternator is charging. Your batteries will not show any more than 12.8 volt unless the alternator is working. On the other-hand, the tach is running off of the alternator but via a separate wire that is connected to the inside. My alternator is connected to the tach by a single wire passing through a hole in the back of the alternator casing and crimped to a ring terminal inside the alternator. If that wire is not making contact your tach will not work. It is possible your alternator warnings will light up due to that problem. That I do not know for sure. I would pull on the wire to see if it's broken from the ring terminal crimp. Also follow the wire into the harness and look for plugin problems like corrosion etc.
Oh, your parking brake light is probably just a burn bulb in the back of the switch. I can't imagine that it could be related to the alternator issue. Remove the 4 screws from the switch panel, pull the panel and check the bulb and connections.
I have a 310c. Probably a similiar set up. When I got the machine the tach and hour meter were not working. Someone had replaced the alt. with an incorrect one. The had to do some rewireing at the alt to make it work. It would charge fine , just no tach or hour meter. We replaced the alt. with one that had the output for the tack and all is well. It has been a while but I think it also made the alt lite come on. But not sure about that. You could have had a bad alt. and the mechanic replaced it with one that does not have the output wire for the tach.