Hi frederick w,
The batteries may or may not be okay. Consider:
1. Check the water (if they have caps you can remove).
2. Fully charge the batteries. This may take several days.
3. If the batteries have caps for you to check the water. While your waiting for the batteries to charge, go to your local automotive store and purchase a hydrometer (not expensive). There should be instructions how to use the hydrometer and what the readings should be. The key is all the cells should be very close to being the same.
4. With the batteries fully charged, disconnect the charger and wait overnight.
5. With a meter check the VDC. It should be 12.6 VDC or more, but not less.
6. Test each cell with the hydrometer.
7. If the batteries do not have caps to check the water, do step #2, 4 and 5.
8. If the VDC checks good, there are two choices.
8a. Stop now and use the batteries as you normally would. They may or may not hold a charge. If you find their life to be short, replacement is the next step.
8b. Purchase a battery load tester. Buy one rated at least 100 AMPS, mine is rated 130 AMPS. With the batteries fully charged test each battery with the load tester. This will tell you, immediately, if the batteries are good or bad.
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