Battery Condition

[Chaos USMC]

Regarding my TYM T-503, most recently, during the first start of the day, it seems to have a battery that "might" be on it's way out. Very sluggish start the first time, but kicks right off on subsequent starts. Granted, temperatures are getting cooler (no lower than 40' overnight) but nothing much cooler.

The closed cell battery has a small visual indicator on top and it indicates green. I measured the battery before starting and it was over 12VDC. I tested the battery with a load tester and it was not perfect, but, not bad. Once the tractor is running I get a little over 13 V at the battery terminals.

The battery is probably 7-8 years old. Because of the very sluggish starting, I am wondering if it is ready to crap out at any time, or, something else is possibly going on. Any battery experts out there that might comment?

Thank you.

 

[CobyRupert]

7-8 years old: Could be on way out.
Like you say it is getting colder out. Do you use a block heater? What is engine oil weight?

A battery below 12.4V is probably partially discharged.
13V when charging may not be enough at lower temperatures to fully charge battery, depending on running time. I think you want alternator putting out something in the 13.8-14.2V range.

 

[metalbender]

7-8 years, the battery has done it's job. Get a new one, higher ah rating in the same physical size if possible.

 

[LouNY]

Before you spring for a new battery, which is quite likely heading out.
You can put a trickle charger on the battery over night then check the first start of the day.
If it's fine thats just another indication that it is the battery, it could be under charging but more likely a weak battery.

 

[jaydee325]

A fully charged 12v flooded cell battery should read 12.6 volts or higher. At 12v, the battery is only 50% charged.

Since you have a low charge voltage and a questionable load test, I'd just replace the battery.

And do yourself a favor, when you bring that new battery home, put it on a charger and fully charge it. Then put it in your tractor.

I'm betting with a new fully charged battery, the charge voltage from the tractor will be higher as well.

 

[CobyRupert]

It's probably the battery, but:

Wouldn't a test be: Charge battery (with a charger above 13.8V) for sufficient time. After charger removed, then, (say) the next day, check battery to see if voltage has stayed near the 12.6V range?

If it stays near 12.6V, it might be a case that alternator wasn't fully charging battery; but if it's going back below 12.3V it's probably battery.

You probably don't have a leakage current (parasitic load) that's drawing battery down, but I'll throw this out here: Another test is to disconnect one terminal of battery from tractor. Then measure if there's any leakage current running through meter (ammeter setting) when you re-complete the circuit by using the meter probes. Do this when all tractor battery loads are turned off. There should be no leakage current that drain battery when off.

...better yet: Do the disconnect and test for leak current at the ground cable where it connects to frame. Then you can clean this connection and make sure no paint or corrosion is inhibiting a good ground connection. Resistance by a weak connection at this location is often a common cause of "weak starting".

 

[Chaos USMC]

Thank you to all, great discussion points.

Went back to the barn and took additional readings at the battery terminals: Static Battery - 12.67V. Turned key on and let glow plugs cycle - 12.18V. After tractor start - 13.5V. BTW, OAT was 47' and tractor is serviced with Rotella T4 15w-40.

I apparently did not have enough cranking amps left after waiting on the glow plugs to warm, she groaned once or twice and then refused to go any further. I quickly cycled the start switch and she "just" barely had enough to start. Put the battery on a maintainer/charger and will check capabilities in the morning.

 

[CobyRupert]

If you went out and found it to be 12.67V, that's what it will probably be tomorrow after taking charger off (and waiting a bit). That is, I doubt battery voltage will charge any higher as this is a "good" number.
But the voltage doesn't tell how much capacity battery has.

Not sure, but glow plugs pulling voltage own to 12.18V might be indication of weak battery. I'd guess that a healthy battery would recover to a better voltage after cycling.
I'd disconnect and clean (wire brush) where the negative cable from the battery attaches to frame to ensure good metal to metal contact. If that doesn't help...new battery should.

 

[WranglerX]

Want to know alot about batteries.....

Car and Deep Cycle Battery FAQ, Battery Manufacturers and Brand Names List, and

Dale

 

[/pine]

A battery like described may last a week or a couple of years yet...regardless if you have not done so I would check all the main cable connections for the battery paying special attention to where the main ground wire connects to the tractor...it may look OK but not be under the washer etc...they are prone to vibration and cause intermittent issues...

Good Luck..