AGM Battery for Old Kubota?

   / AGM Battery for Old Kubota? #1  

Suburban Plowboy

Veteran Member
Joined
Jul 31, 2018
Messages
1,104
Location
FL
Tractor
Kubota L3710
A tester says my Kubota L3710's 2019 Autocraft Gold non-AGM battery is reaching the end of the line. Is there any point in getting an AGM battery for an old tractor? I don't know whether an AGM battery will like the Kubota's charging system.
 
   / AGM Battery for Old Kubota? #3  
agm doesn't really gain you anything, unless you need to mount it weird, or have other issues. if the original lasted 14 years get another normal one.
 
   / AGM Battery for Old Kubota? #4  
I like the AGM batteries for a couple of reasons, the biggest is no outgassing so no corrosion on the terminals and cables. And in the same vein as no outgassing they are much more tolerant of steep hills with no leakage.
 
   / AGM Battery for Old Kubota? #5  
Don't AGM batteries need to be at 12.8 volts to be fully charged?
As opposed to 12.6 volts for a flooded lead acid battery?
Not sure if the regular charging voltage will be sufficient?
Curious!
 
   / AGM Battery for Old Kubota? #6  
Don't AGM batteries need to be at 12.8 volts to be fully charged?
As opposed to 12.6 volts for a flooded lead acid battery?
Not sure if the regular charging voltage will be sufficient?
Curious!
You can buy an alternator to match the output to get the charging voltage needed for an AGM.
The AGM carbon type batteries I use need to be charged to 13.2 volts for a full charge, but are fine at 12.6 to 12.8 volts to start my trucks.
Carbon AGM's have a very low discharge rate even in cold weather and they can sit for 6 to 8 months and still have enough capacity to start a vehicle.
A lead acid would need to be charged a couple times in this timeframe especially if below freezing temps are involved.
 
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   / AGM Battery for Old Kubota? #7  
The charging algorithms are similar enough between AGM and standard batteries. The advantages of AGM are a lower self discharge rate, no off-gassing, and vibration resistance. They supposedly last longer, but I haven't noticed that when both battery types are well maintained.
My preference (even though they are more expensive) is AGM batteries.
 
   / AGM Battery for Old Kubota? #8  
After I had standard lead-acid batteries leak and destroy the front of two tractors, I switched to AGM or sealed batteries. I went to AGM whenever they first came out and have them in everything from the truck on down to an old tractor.

They're a few dollars more but that's cheap money. No more ruining the front metalwork on my equipment. Modern smart batteries like Genius chargers have a setting for AGM. I charge batteries just before winter and sometimes during winter and have several AGM and older sealed batteries well over 10 years old.
 
   / AGM Battery for Old Kubota? #9  
I like the AGM batteries for a couple of reasons, the biggest is no outgassing so no corrosion on the terminals and cables. And in the same vein as no outgassing they are much more tolerant of steep hills with no leakage.
Looks like you got a lot of "likes" with that reply. I'm one. It sure is nice not to have to deal with terminal and cable corrosion.

To the OP, you can replace the original non-AGM battery with any AGM type that physically fits the space. It will charge and work just the same as the original. Well, actually that isn't completely true; the difference is that "full charge" will be very slightly reduced. But it is so slight that it is difficult to measure. Neither you nor the tractor will know the difference in how the battery works.

The original wet cell on our 60 hp Kubota lasted a long time during which it corroded one cable set and several terminal clamps. I replaced it with an Interstate Group 24 AGM battery that was slightly more expensive than the old flooded cell type. It has worked well for us.
rScotty
 
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   / AGM Battery for Old Kubota?
  • Thread Starter
#10  
I read this thing might not be happy with the Kubota's charging system, so I went with Walmart's second-tier battery. Thanks.
 
   / AGM Battery for Old Kubota? #11  
I read this thing might not be happy with the Kubota's charging system, so I went with Walmart's second-tier battery. Thanks.
agm charging vs lead acid is "almost" identical. I would like to know what it's not "happy" about.
 
   / AGM Battery for Old Kubota? #12  
agm charging vs lead acid is "almost" identical. I would like to know what it's not "happy" about.
Well, this is the internet. There is a lot of incorrect info out there. Science appears to have taken a nosedive relative to opinion.

It won't hurt anything for the OP to have an old style battery; he can switch next time - or not.
I'm finding that most lead/acid batteries don't last as long as they once did.

AGMs and flooded cells types are both lead/acid and are interchangeable when used alone. For the large older diesels that use two 12 volts batteries in parallel, I would use both of the same type.
rS otty
 
   / AGM Battery for Old Kubota? #13  
While a NAPA store salesman,I was working with the battery rep.
A customer had 2 AGM's in a boat with twin 502's,replacing his flooded lead acid batteries.
His AGM's were junk after one year.
Rep stated the batteries weren't charged enough with the stock charging voltage,and were a constant,partially charged condition,with the resulting decline in life.
He mentioned the 12.6 vs. 12.8 voltage requirement.
About 5-6 years ago.
Still Curious!
 
   / AGM Battery for Old Kubota? #14  
Interesting. I replaced the standard flooded units in my SeaSport with AGMs 9 years ago. Still test and work just fine.

[edit to add] They spend most of their time on a smart (brilliant...) charger. Perhaps that has helped.

Z.
 
   / AGM Battery for Old Kubota? #15  
While a NAPA store salesman,I was working with the battery rep.
A customer had 2 AGM's in a boat with twin 502's,replacing his flooded lead acid batteries.
His AGM's were junk after one year.
Rep stated the batteries weren't charged enough with the stock charging voltage,and were a constant,partially charged condition,with the resulting decline in life.
He mentioned the 12.6 vs. 12.8 voltage requirement.
About 5-6 years ago.
Still Curious!
For someone that knows more, does that sound right?
 
   / AGM Battery for Old Kubota? #16  
Pretty much every 12v system I have checked runs above 13v when the alternator is functioning correctly. Most are 14+ at operating speed, so plenty of voltage to charge either battery. I have used AGM in everything from ATV, tractors, cars and rvs. Never noticed a problem.
My ancient Honda ATV like to blow regulators (know issue on that model) but even it puts out 14+ at speed and 12.8 at idle. Been running AGM batteries for 12 years, second one installed a few years ago. The both were cheap Chinese batteries and seem to last 7 or 8 years and I drain them too often when using the winch to tension fencing.
Due the regulator issue I installed a voltmeter on the quad to keep an eye on it.
 
   / AGM Battery for Old Kubota? #17  
For someone that knows more, does that sound right?
No it doesn't sound right!

I worked as a tune up scope technician in the 80's and part of the job was training ASE certified automotive mechanics the in and out of reading waveforms and also training them on SAE standards.
The standard for alternators from recall is SAE 56 I believe. This standard requires the engine idle amperage output and the 5,000 or 6,000 rpm (of the alternator) output and the voltage output to be stamped on the alternator. Should see something like 30/115/13.6 With the 30 being the idle amps, the 115 the 5000 rpm amps, and the 13.6 the voltage ouput of the alternator.
The only way the batteries in the boat could have gone bad would be that they added auxilary circuits (extra loads) to the battery. This was common with cars when kids would add thier 400 to 500 watt stereo as a load on the battery. The alternator just can't keep up with heavy loads that it was never intended to have. Edit: thus making the battery be constantly undercharged.
 
   / AGM Battery for Old Kubota? #18  
While a NAPA store salesman,I was working with the battery rep.
A customer had 2 AGM's in a boat with twin 502's,replacing his flooded lead acid batteries.
His AGM's were junk after one year.
Rep stated the batteries weren't charged enough with the stock charging voltage,and were a constant,partially charged condition,with the resulting decline in life.
He mentioned the 12.6 vs. 12.8 voltage requirement.
About 5-6 years ago.
Still Curious!
For someone that knows more, does that sound right?
No. Not that I doubt the story, but the failure had some other cause than the change to AGMs.
Charging voltages are typically high enough to fully charge either type battery,
rScotty
 
   / AGM Battery for Old Kubota? #19  
Agm batteries take a different charger algorithm than standard lead acid batteries. My NOCO Genius even has a separate charger setting for it.Heck, i even had to reprogram my F150 to allow charger to properly charge the new AGM battery.

Not saying a standard charger wont work, but it probably will effect the battery life span and charge.

Generac generator had to change their charger system to allow charging AGM batteries in their newer controllers.


Just saying.

Me, i just used standard lead acid in my tractors. Have for 28 years.
 
   / AGM Battery for Old Kubota? #20  
My 2008 Massy came factory with an AGM battery. It just died this summer. Over 15 years.

The tractor has no digital charger control that would be required to tailor a charge ‘algorithm’ to either an AGM or a standard battery. The alternator simply puts out about 13-14 volts at speed, and drops to about 13 volts at idle. It doesn’t care.

The charging of the battery is highly influenced by how long and often I low idle and how long and often it’s at higher rpm’s.
Of course how often it’s started is a huge influence.

I replace the AGM with a standard battery. It doesn’t matter.

12.6 or 12.8 volts is the battery resting voltage, not the charge voltage. Your tractor isn’t cycling a float charge like a little battery tender.
Install either type.
 

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