mahindra 5500 chargin only 12.4 volts new alt

[EugeneStanley]

mahindra 5500 chargen 12.4 volts rebuilt alt

 

[thekkfan]

sounds like you got a faulty reman. Is the regulator in the alternator?

 

[nyone]

Why did you change the alternator? Not charging? I would say your problem is not the alternator. Have you checked the voltage at the alternator? Fuses?

 

[Jerry/MT]

Sounds like a bad regulator or bad wiring. Is the alternator correctly hooked up to the wiring? It should be charging around 14 volts+/-

 

[jaydee325]

Electrical trouble shooting 101: Start with a known good, fully charged battery. My suggestion is if you have not pulled the battery, fully charged it and had it load tested, that is the next step.

 

[John_Mc]

Electrical trouble shooting 101: Start with a known good, fully charged battery. My suggestion is if you have not pulled the battery, fully charged it and had it load tested, that is the next step.

Definitely the place to start on this. Check electrolyte levels (if it's the type of battery that allows that), charge it on a good quality external charger, then load test it.

If you don't have a load tester, charge it fully (e.g. overnight), disconnect from charger and tractor, check voltage, then check voltage again the next day, after the battery has "rested" 8 to 12 hours. The table below shows voltages and state-of-charge for a regular flooded lead-acid battery (these can be either sealed "maintenance free" or the kind with filler caps). AGM batteries can run a bit higher voltages (depending on brand), Gel batteries tend to run a bit lower.

no load volts	% full charge
12.9-13.1	100%
12.6-12.9	75%
12.4-12.6	50%
12.2-12.4	25%
12.0-12.2	0%
<11.0	shorted

If the battery is showing anything under 100% after charging and then allowing that 8-12 hour rest, it has a problem. If it's about about 12.4 volts, there is a good chance you can recover it by connecting it to a quality charger or maintainer with a desulfating feature. It's worth trying if the battery is below 12.4, but the odds are less for a full recovery the lower the voltage. If the battery is internally shorted, you might as well throw it out. (NOTE: Being under 12.4 before attempting charging is not good for the battery, but it does not necessarily mean the battery is shot. The voltages above assume a thorough charging with the rest period before testing.)

I've recovered a number of weak batteries with the BatteryMinder chargers. You can find several models on Northern Tool: Their current models include temperature compensation and are able to recover much more deeply discharged batteries. For an inexpensive charger/maintainer, look at the model 1500 or 1510. The deluxe end of their lineup includes the 128CEC1 (selectable 2/4/8 amp charge rates, custom charging profiles for Gel, Flooded Lead-Acid, and AGM batteries, etc). The older BatteryMinder 12117 model used to be one of their big sellers, but now is sold only through Northern Tool. They're decent, if you are looking for one of the most inexpensive desulfating maintainers out there, but the newer battery minder chargers/maintainers are much nicer.