641 charging light

[Jo Knight]

My red charging light keeps coming on...I had the generator rebuilt and thought this would fix the problem. It is still on after I put the rebuilt generator back on my tractor. Any advice to get this darn light off would be appreciated.

 

[awhtx]

Did you ignore the voltage regulator?

 

[Jo Knight]

No, I took it in when I got the generator rebuilt and they tested it and said it was ok.

 

[awhtx]

Use your voltmeter to confirm that the generator/regulator is not working correctly then take it back to the rebuilder.

 

[raycole]

I had a bad wire on my 641 that caused me not to get a charge. I had tested the generator and it looked good. Had the regulator tested and it was good. Turned out just being a bad wire - guess it had a break in it somewhere or (probably more likely) the crimp-on end of it was not doing so well. May not be your issue, but don't overlook the wires.

 

[RickB]

I'm increasingly fond of swapping out the wiring harnesses on these old tractors. Doing so seems to eliminate the random problems with charging and ignition; especially when troubleshooting has suggested that major components are functional. $65 will buy a complete main harness for that 641 without even shopping around.

 

[JMOR]

(quoted from post at 07:15:16 04/30/10) My red charging light keeps coming on...I had the generator rebuilt and thought this would fix the problem. It is still on after I put the rebuilt generator back on my tractor. Any advice to get this darn light off would be appreciated.

o, see diagram. When all is well with gen charging/reg regulation/wiring OK/etc., then all the wires I marked in red are at same voltage (terminals 'A' and 'B' are connected inside reg), which means that both sides of warning light are at same voltage, thus no current flow & no light. Your mission, should you choose to accept it, is to trace/probe those wires until you find out why they are not all at the same voltage.