Please someone help me to get my alternator to charge. prior to my ownership someone split backhoe and never rewired it. My service manual doesn't have detailed wiring schematics. My alternator also has no 2 wire plug on the side. pictures drawings schematics are all welcomed.
Can you post a picture of the alternator? These machines are old enough that anything could be transplanted on it. Mel.
Ok I can do that after work. Update I did remove cover on alternator and replaced with a plug. I was able to find plug from an old gm alternator.
If the plug opening had a rubber plug it was set up for a one wire alternator, It needs no further wiring, just one heavy lead, a big red wire from the ammeter that is hot all the time fastens to the rear of the alternator on the large post. If the alternator is in good shape it should charge just running it but those alternators require the rpms to be run up high sometimes, depending on the individual alternator to start a charge. I convert those alternators to a special AC excited regulator because that is much superior setup, The diode trio is removed and a couple internal wires that sense AC when the rotor turns and switches the DC from the internal rectifier to excite the fields, that setup is a very low excitation alternator, My 830 Case charges 30 amps at just above idle, probably 1100 engine rpm with a modified 10SI with the D10AC regulator.
How did u wire the plug, The RH wire looking ahead should loop down to the big terminal with the red wire and the other to the original exciter wire from the underdash resistor
Wow that's exactly what I kind of figured. I did not wire the plug just installed it in because I was unsure of how to wire it correctly. My hand held meter did indicate that I was getting about 12.9 volts of charge at low rpm. I only run at about 1100 rpms so that would also explain the low charge also. I do have the heavy gauge wire at the back of the alternator. i think that it routes to the ammeter. The ammeter does not work.
Check the output voltage at higher rpm, that engine idles at around 900-1000 rpm, you should see 13.8--14V or a little more. If the voltage goes up to that area you do not need the plug as it is working as a one wire should. Just put the plug back in. On a different note but what do you use the machine for that you run the engine so slow. Backhoe functions tend to smooth out and not be so jerky at higher rpm. They are designed to operate up there. The battery will not stay charged with 12.9V. Another issue that I have found many time on those hoes is loose fan belt tension. if the belt is not pretty tight the belt will slip. Run it up to speed for a few minutes, shut it off and feel the front face of the alternator pulley carefully, If it is extremely hot tighten the belt. Those engines have a kinda short adjusting strap on them and many times the bolt is against the end of the slot. They have a very stingy ammeter from new, if you look carefully you may see a little movement. You should also look for voltage rise at the battery +/- terminals or big battery cable to ground at starter.