I just put my older lead acid flooded cell battery on the CTEK battery charger. i can't tell if I need to take it off and try and fill the cells with distilled water? or is it better just to leave it alone?

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If you can remove the caps then I'd check the electrolyte levels. If the cells are low then you can top them with DISTILLED water only! If they are almost full then I'd leave them alone.

Put it on the maintenance mode and allow to charge until you get the green light.

A good quick video.

https://www.youtube.com/watch?v=qS6evjtqy6Y

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“Whatever story you're telling, it will be more interesting if, at the end you add, "and then everything burst into flames.”
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Thank you for the advice Mike, I will see if I can remove the caps and if so, fill it with distilled water.

Let the Battery warm up allowing the already in water (of course add enough to cover the plates) in the battery to expand before adding the water.

Or add the water to a cold battery at the lowest level and recheck it later when the battery is warmed up and fill as needed.

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84 300D, 82 Volvo 244Gl Diesel

What voltage are you seeing resting?

What indication do you have that the water is low?

Worth looking, but not sure you’ll need to add.

Maintenance charging to full is always a good idea!

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