Fun With Batteries (Best Tug A3)

Stewartb

Final Approach
Joined
Nov 21, 2014
Messages
8,616
Location
Wasilla, AK
Display Name

Display name:
stewartb
Left it on for a week. Batteries are too dead to initiate a charge with the supplied charger. Off with the shroud to find two cheap sealed lead-acid batteries in there. One tests at at 4v, one at 0v. The 4v one will initiate a charge on my shop smart charger. I got it up to 6v and jumped it to the 0v battery to tickle the charger to initiate on the weaker battery. So far, so good. I won’t know for a day or two whether I can resurrect these batteries back to useful or if I have to replace them. I doubt they’ll ever be the same but they may be good enough. I think I’ll get in the habit of plugging my tug in when not in use!
 
Left it on for a week. Batteries are too dead to initiate a charge with the supplied charger. Off with the shroud to find two cheap sealed lead-acid batteries in there. One tests at at 4v, one at 0v. The 4v one will initiate a charge on my shop smart charger. I got it up to 6v and jumped it to the 0v battery to tickle the charger to initiate on the weaker battery. So far, so good. I won’t know for a day or two whether I can resurrect these batteries back to useful or if I have to replace them. I doubt they’ll ever be the same but they may be good enough. I think I’ll get in the habit of plugging my tug in when not in use!

Josh at best tugs said if they are below 2 volts they are junk. My A3 showed up in the wood crate on and the battery's dead both around 1.5 volts. Best tugs promptly sent me 2 new battery's.

I leave my light on all the time, it acts as a pilot light to remind me if I forget and leave it on.

Yes a smart charger needs volts to work.

I hit both of my dead batteries with a "old fashioned" roll around 15/30/70 amp/125 amp jump starter battery charger. I was able to save them I think? They have been holding a charge for 2 years now. I have used them for light duty, never got around to swapping them back into the tug to see if they really worked under heavy load.
Good luck with yours, hit em with big charger at first to get em going.
I left mine on a battery minder too after the big charger got them up to speed first.
(edited)_IMG_7472.JPG

If you lived closer I would give you these. Been sitting on my work bench for 2-3 years now. I keep them charged with my 24 volt battery minder.
IMG_1117.JPG
 
Last edited:
I have both batteries up to 70% charged. I’m alternating the charger back and forth so I don’t overcook a battery. I’ve done that a few times before. I doubt these will charge to and maintain a full charge but it’s something to do in the hangar with a beer on another rainy day.
 
Those are probably standard batteries. They don't have as big a selection as they used to, but allelectronics.com has been a good source for me in the past. Some of the stuff they sell is new, but to my knowledge their batteries are new. Gel cells, if that's what they are, are really reliable and great because they don't leak, but they're easy to damage by overcharging, because once the water gets boiled/vaporized out there's no way to get it back in...or at least that's my understanding. Newer, bigger, more expensive SLAs are AGM, that are more robust.
 
They are 22ah 12 volt sealed lead acid batteries aka gel cells. Readily available for about 60 bucks each.
 
My technique worked. The batteries are both charged to 100% and the tug is plugged in to maintain a float charge. How they handle a workload? That’ll have to wait until the rain subsides.

I did the exact same thing with the exact same tug, with the exact same results (right down to one battery being 0 V), about December or so. Brought them home so I could bring them back to life in a warm environment, got them going again, and now they are fine and handle the load of the plane apparently just as well as before. I think you'll be good.
 
I did the exact same thing with the exact same tug, with the exact same results (right down to one battery being 0 V), about December or so. Brought them home so I could bring them back to life in a warm environment, got them going again, and now they are fine and handle the load of the plane apparently just as well as before. I think you'll be good.

So far, so good. I think the batteries discharge a lille faster than before but they have plenty of duration for now.
 
Back
Top