Hello, I have a 2001 Bobcat 322D Mini Excavator and I didn't want to pay 250.00 for a bobcat alternator so i bought the 85.00 china alternator off ebay. This thing has zero output and I only have battery voltage from positive from the alternator to ground while running. The belt has proper tension but no output. I read somewhere I may need to flash the field of the alt. if it has been on the shelf awhile. Any suggestions on how to do this or do i even need to do it. Can anyone give me some direction? I guess the new alternator could be bad? Thanks! Greg
To work reliably an alternator needs to be excited to get it up and running every time the engine starts. This can be done a number of ways but the most common is using the charging light indicator bulb. The small current passing through the bulb is enough to start the alternator. So ether your bulb has blown or there is a mismatch with the small wires plugged onto your alternator. You will need to post a picture of the back of the alternator showing detail of that small plug and as much detail as possible.
I will check yhat, I know for sure i have a bulb out because it was busted. I had to pull it out with needle nose to get it out, I will replace and see what happens. Thanks!
there are 4 lights on the armrest that are red, each assembly has 2 lights and are sealed. 3 of 4 work, the one that doesnt has a pic of a battery on it. I also checked the plug leaving the alternator and it is wired correctly Here is a pic of the plug on the alternator.
Hmm is this the charging light you spoke of 007? I will check to see if i have voltage to the light.
Okay, I have replaced the indicator light, actually swapped wires from the glow plug light and still alternator not charging.
Turn the ignition on, but don't start the engine, does the battery/low voltage indicator light turn on? In the old days, that meant that the alt was drawing current, which meant that the wiring was all intact, and the alternator should function. If the light doesn't light up, then it could be the alternator, OR the wiring, and you'll have to check for voltage at the small terminals on the alternator, engine doesn't have to be running, just ignition on. You're talking about flashing a generator, I've never heard of doing anything like that for an alternator.
Thanks Delmer, With Key on the battery? low voltage does not come on, I will try to follow the wiring and to make sure thats good.
I'd start at the battery warning light bulb, check if it has ground on one side (at least a fairly low resistance to ground) and then battery voltage on the other side with the ignition on. And probably a somewhat low resistance to ground with the key off, could even disconnect the other "ign" circuits and see if the resistance increases. you probably want a wiring diagram, if the circuit comes through a module, or printed circuit board, it's a dead end tracing wires.
Greg if you would like a diagram please provide your serial number and email .
Sorry greg did not realize you were not up and running. The pic does not show any detail. Normally in the cast frame of the alt is some symbols which represent what the three terminals are. Some more pics of the back of the alt so i can recognize what you have there would help. Is it the exact same plug as your old one is? Did you receive any info with the new alternator?. Take a pic of the back of the old alternator also if they are different. If the alternator has an internal regulator it only needs one wire from the bulb to get it up and away. Use your multi meter with the plug off the alternator and check the machine side and figure out which wire has voltage appear on it when you turn your ignition on. Lets start with that. If tool_king sends you the wiring diagram you can send that to me also. Cheers
Thanks there are 2 lights in each assembly, I swapped my wires from one to the other because the light was working on the other but i do not get a light on either now, both have grounds and both have battery voltage which is around 10.25 volts (battery voltage) that is very nice of you. S/N 223513501 [email protected] Thanks again!
I just use a lithium jump starter and it runs like a top, so im running. going to be hard to get pics considering location of the alt. I may have to pull it. The plug on the new alternator is exactly like the old one. Did not recieve any info with the new alt. I will ck voltage and see which pin has voltage.
Your not making it easy to help. 10.25volts is beyond flat battery's but alt should still get away ok. Here is a simple test for you based on an alternator with a internal regulator. The add from ebay should at least confirm whether it has internal regulator. If you make up a small wire to go between the battery positive and the alternator to do some tests. Make sure the wire has a small bulb at least 2watts in series in the wire. So if you short the wire to the ground metal of the machine the bulb will illuminate. Make sure you have good battery positive potential on the large output terminal of the alternator. Run the engine with above idle rpm's. If you strip the end of the wire so you can flash the terminals in the alternator. You carn't hurt the alternator. The three terminals could be anything but one might be star point, one might be ground, and one is almost certainly where the bulb is connected. If you flash the wire on each terminal momentarily when you get the right terminal the alternator will spring into life. If that turns out a fail we might have to wait until you get that circuit diagram. Cheers.
It might be easier for you to get some mini spade connectors and run three wires out of the engine compartment so you can touch them to the battery positive not reaching into the back of the alternator. Double check your voltages, 10 is low, but it should still light up the warning light fine, and excite the alternator fine also. Check the voltage on either side of the light bulb WITH the light bulb in PLACE. It's easy to get voltage with no load, and a bad connection that won't carry any current with a load in place.
Yes your right about the wires but there is no touching the battery positive without that bulb in circuit or the color of your day could change quickly.
Here's a little bit of new info. This machine is located up in the mountains and I can't get up there very often, sorry to be so slow. I took voltage at the male plug that goes to the Alt. and I do have battery voltage on one spade with key on. There are only 2 wires feeding the plug.
Having trouble finding a 2W bulb. I noticed the male plug going into my alternator has 3 wires but only 2 are being used the other has been cut. I took voltage between the 2 wires with the key on and have battery voltage.
This doesn't make sense. figure this out. Swap the bulbs again, if the original one works again, then get another new good bulb. Can't have voltage, ground, and a good bulb and no light... Is this a nippon denso style? was that on the original alternator? You can look up a wiring diagram for the ALTERNATOR model/make and use the old one as a test mounted in a vice at home so you know it works and figure out the wiring. I'd use any turn signal or marker light off a junk car for testing like 007 said, but I've never had trouble touching the hot wire to alternator terminals.
I was up on the mountain yesterday and did some more checking. There are 2 lights in the sealed module. one is battery and one is glow plug. The glow plug light used to work so i swapped the 2 battery wires over to the glow plug light. At that time I thought I had voltage and it should light up but it didn't I guess no voltage. I currently have voltage through the 2 glow plug wires. I do not have voltage on the battery wires. I swapped the wiring back to original and now the glow plug light does not burn, maybe the bulb opened up?
Manuals emailed to you .
Does anyone know if the Bobcat 322D Diodes are a plug in style?
UPDATE: I have ordered the new battery/Glow plug light indicator and I found that the alternator feedback diode was open in both directions. Waiting on the parts now and will update again after installation, Thanks for the help!
Okay folks, Finally figured out why I wasn't charging with a new alternator. The Alternator feedback diode located just beneath the starter was open, after replacement I am now getting 14.21 VDC. Thanks for all your help trying to help me. A $6.23 diode caused a lot of heartache