Alternator with attached series resistor

[poccur]

Have bought a John Deere engine and the alternator (Bosch) has a series resistor (in shrink tubing) hanging from it. Nobody seems to be able to say what the long term effect on the engine will be of removing it (the engine runs fine without it). I am guessing that it is used by the regulator of the alternator so it can current sense and decide if it needs to be charging or not.
If anyone can give a definite answer I would appreciate it.
John Deere actually said they were not sure exactly what it did!!!

 

[statorwinder]

Two (2) posibilities
1. substition for a idiot light that is used to excite the regulator.Full battery voltage could eventully destroy the regulator trio circurity.
2.sub for a thermistor that is used to measure the battery temp which lets the alt start to charge.

have seen jd tractors wired with idiot lite or wired thru this resistor for alt excition.
also same with the thermistor some have it some dont,but must have the correct alternator for proper operation if the thermistor is used, or the resistor added.
think this resistor has a value of around 250/300 ohms.