1066 batterys boiling

[henryv11]

Have 1066 12V 2 six Volt battery's in series. With motor running at 12V reads 13.7 and each indv. battery 6.8 & 7 volts. The fluid boils out of battery's does not appear to be overcharging.
I wonder why it would do this

Thank You.

 

[Bob]

(quoted from post at 08:15:10 04/15/20) Have 1066 12V 2 six Volt battery's in series. With motor running at 12V reads 13.7 and each indv. battery 6.8 & 7 volts. The fluid boils out of battery's does not appear to be overcharging.
I wonder why it would do this

Thank You.

If your voltage readings are accurate it's time for new batteries.

 

[Janicholson]

Sulfation in one or more cell will do two things. It will discharge that cell in a modesst amount of time when shut off by self discharge, and act like a resistance to heat up when the charging system gives it voltage. (which may appear to be much more than its 2.2 actual normal volts because it is not doing its intended task. Replacing both is probably wise. I would put 2 12v batteries in parallel to make it easier to buy new ones (options for more CCA, less money). Jim

 

[Brownie450]

How old are the batteries??
Jim

 

[JimB2]

If it has an alternator, I have seen where one or more diodes on the rectifier circuit short and it puts an AC Volts on the battery causing them to boil.
Take the Battery lead off the alternator and see if the boiling stops.
A Digital VOM will not show the AC while measuring DC Volts, the old analogue VOMs you could tell when there was an AC on the DC by the meter needle vibrating.

 

[caterpillar guy]

If you go the replacement battery route, just put a group 31 stud top battery in it and forget about those long skinny ones. They don't last as well as the 31's and with the stud top in place of a post they will be much less maintenance over time.

 

[fixerupper]

When I smell battery in the cab of the 1086 I know it's time for new ones. It happened to me a few weeks ago as a matter of fact. When I pulled the old batteries out I was surprised they were 15 years old. I Can't complain about that.

 

[Krhaff13]

Bob,

I have an 8630 that fused the reverse gear to the shaft. We replaced the shaft, fused gear, clutch pack, synchronizer, and reassembled. The thing ran for 30 minutes fine pulling 26 sweeps. I had to back into a corner and as soon as did, it happened all over again. Do you think it could be the transmission pump not supplying lube to the rear of the assembly where the reverse gear is more situated?

Thanks,
Kris