Mahindra Battery Terminal Corrosion

   / Mahindra Battery Terminal Corrosion #31  
So could the battery be bad, even if the charger says it's fully charged?

Not knowing how much you have worked on stuff, it is hard to recommend something. But if it were me [ disclaimer here ], I'd turn the key to on... then jumper from the big 12v postive lead on the starter to the little solenoid terminal... and see if she would turn over and/or start that way. That bypasses all the little wiring and switches [ ie:safety switches ].. But you have to be smart enough to make sure the tractor is in neutral, etc... If that does not do anything.. then you probably have a loose or bad big cable going to the battery [ don't forget the ground cable on the frame ], bad solenoid or starter, or could even be an open inside the battery itself. Like the above post, voltmeter is really what you need... Good luck, Jerry....
 
   / Mahindra Battery Terminal Corrosion #32  
A battery with an open or bad cell... would do it. Even if you check it with a voltage meter... and it show voltage.. once you try to get some juice [ draw current ] out of it it will quickly show low voltage.. If that were your problem, the tractor would probably start normally when you junped it with another vehicle..
 
   / Mahindra Battery Terminal Corrosion #33  
If you had a bad or open cell, no way it would show 'correct' voltage.
 
   / Mahindra Battery Terminal Corrosion #34  
If you had a bad or open cell, no way it would show 'correct' voltage.

It may show correct voltage right when you remove the charger... but then drop down. But, when the charger is running... with a bad cell... or open.. it can and will show correct voltage. [ just like if the battery were not there... which if it is bad... it isn't... ]
 
   / Mahindra Battery Terminal Corrosion #35  
Got it working. Read a couple of threads here with people with a similar start problem, and both mentioned connections that were not as secure as they should be. So I went back and disconnected everything, cleaned, brushed, and secured the end better/tighter, and it started up. I probably need to solder the end instead of it just being a bolt connection, that will be for next weekend.

Thanks for the help.
 
   / Mahindra Battery Terminal Corrosion #36  
BillyCrash said:
Ok, I changed the terminal end, trickle charged the battery (charger indicates battery fully charged). Turn the key to the first click and I have indicators, and a kind of buzzing sound. Turn to second click for start and nothing. Checked fuses, all ok. Checked safety solenoid on HST pedal, appears to be engaging. Is there a safety solenoid on the clutch as well? Pushed the clutch in and moved gear selector through all gears, back to neutral pre-start, still nothing. Any ideas?

My tractor has done what you describe a couple of times. Each time it was a corroded battery cable end. Did you clean the battery post?
 
   / Mahindra Battery Terminal Corrosion #37  
Got it working. Read a couple of threads here with people with a similar start problem, and both mentioned connections that were not as secure as they should be. So I went back and disconnected everything, cleaned, brushed, and secured the end better/tighter, and it started up. I probably need to solder the end instead of it just being a bolt connection, that will be for next weekend.

Thanks for the help.

Refrence post 11, I consider the clamp on ends as a temporary fix, solder is the way to go.

Dave
 
   / Mahindra Battery Terminal Corrosion #38  
Time to take the battery to you favorite parts store and have them do a load test. I would lay money on it being bad. I have had new ones not pass a load test. I just had this very same symptom problem with a Ford Explorer. Screwed around like you did, finally bit the bullet and bought a new battery.. It worked right out of the store. Oh! I cleaned every thing mup with boiling water bas described in my earlier post this subject.

Ron
 
   / Mahindra Battery Terminal Corrosion #39  
Time to take the battery to you favorite parts store and have them do a load test. I would lay money on it being bad. I have had new ones not pass a load test. I just had this very same symptom problem with a Ford Explorer. Screwed around like you did, finally bit the bullet and bought a new battery.. It worked right out of the store. Oh! I cleaned every thing mup with boiling water bas described in my earlier post this subject.

Ron
 
   / Mahindra Battery Terminal Corrosion #40  
So could the battery be bad, even if the charger says it's fully charged?

Yes a battery can be bad and still show that it is fully charged. You can get a charger or a volt meter to fool you like this since not all failures are from a shorted cell, in fact most are not.
Batteries live in one of two states they are either charging or discharging there is no middle ground once charge current and voltage are removed the battery starts to discharge. The discharge rate is a function of a number of things to include chemistry (calcium, antimony mixed with the lead in the grid), temperature and construction (AGM, flooded etc.). As the battery discharges the by product (chemical reaction) is PbSo4 the longer the battery sits in a discharged the larger the crystals become. When the crystals are small any charger or alternator can break them up but the longer they sit in a discharged state the larger they become and then they are basically keeping you from accessing the active plate material. So whatever portion of the plate is covered is not available for you to use that is why you can have voltage or show fully charged but have reduced or no capacity.
The corrosion issue has been well addressed, that acid you see around the caps is from the battery being overfilled the corrosion around the terminals is because even with the o rings around the terminals and all the other methods there are to seal them you are actually getting leakage a molecule at a time around the terminals. That's because the plastic and lead expand and contract at different rates, the previously mentioned molecules then recombine and give you that acid bloom. Because of how it escapes and recombines the sprays and felt rings work.
The poster that talked about using boiling water to clean them up is probably dead on but if you are in a shop where you have EPA oversight I'd recommend against it since the acid residue is ending up on the ground. He is right about not getting baking soda in the battery because it will ruin it but the caps are one way vents so if they are properly in place you won't get any inside. I'd recommend you use a solution of baking soda, water and dish soap that way you neutralize the acid and wash it off at the same time. Ammonia will also neutralize the acid.

Sorry for the long post but I teach this to Marines and civilian companies as part of my job so I saw it as a way to contribute. You go to http://read.dmtmag.com/issue/45512 for more information on the effects of sulfation, how our pulse wave form breaks up the large crystal lead sulfate and some things you might find useful if you have a shop full of battery dependent equipment or you can PM me and I'll answer whatever questions I can. You might have to cut and paste the URL.
 
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