Deere 2755 charging "problem"

[jCarroll]

Son has a 1987 model 2755 tractor. Information from him is by phone - I have not had my eyes on the tractor.
Tractor was having low battery symptoms when starting. When started, the voltage at the batteries increased,`
giving evidence the alternator was working.

He replaced the (two) batteries with new ones, fully charged. When started, the battery voltage did not change,
indicating (maybe) the alternator is not charging.

Is this an alternator problem? If yes - where next?

Thanks in advance for your advice and experience.

 

[Jim.ME]

Son has a 1987 model 2755 tractor. Information from him is by phone - I have not had my eyes on the tractor.
Tractor was having low battery symptoms when starting. When started, the voltage at the batteries increased,`
giving evidence the alternator was working.

He replaced the (two) batteries with new ones, fully charged. When started, the battery voltage did not change,
indicating (maybe) the alternator is not charging.

Is this an alternator problem? If yes - where next?

Thanks in advance for your advice and experience.

My thoughts are testing is required before one can say if it is an alternator problem. Testing with a V-O-M is required to start with. Voltage at batteries, voltage at alternator output not running, same with the engine running half throttle or so. Check for voltage draw when the engine is off, etc. The basic checks are the same as most charging systems. Check cable connections and plug together connectors. Make sure the alternator belt is tight.

The 2755 Tech manual should have recommended checks and voltages that should be seen , and where, for the checks beyond basic. TM4436 is the Operation and Test technical manual, there is a supplement TM4436S to that that looks like it has info related to the Sound guard cab, if his tractor has one, and TM4434 is the repair manual. The TM4436 and TM4436S will have the wiring diagrams and testing info. the TM4434 is the manual for the "wrenching" part of a repair. You may want to check eBay for pre-owned, they are not inexpensive.

 

[Fixingfarmer]

14.2ish on the voltmeter when running at alternator and at battery should be pretty close to the same he may or may not have a problem more than possibly an inaccurate gauge. Depending where his gauge is indicating it might just be his new batteries solved his problem

 

[LarrySTN]

Son has a 1987 model 2755 tractor. Information from him is by phone - I have not had my eyes on the tractor.
Tractor was having low battery symptoms when starting. When started, the voltage at the batteries increased,`
giving evidence the alternator was working.

He replaced the (two) batteries with new ones, fully charged. When started, the battery voltage did not change,
indicating (maybe) the alternator is not charging.

Is this an alternator problem? If yes - where next?

Thanks in advance for your advice and experience.

If the 2755 has a Bosch alternator, I would be suspect of it. I have a 2750 and before it was 5 years old the alternator gave lots of trouble. I finally threw the Bosch in the trash and installed a Delco 10si, which has worked all these years since.