Re: Which Battery Tender to Use
I would not keep any charging unit attached to the battery 100% of the time, especially if I could not check it every few days. Too many times since I have been on this forum someones battery has been fried, due to overcharging. I think that the auto cut off fails and the battery gets a 100% of the current all the time which heats up the acid which slowly evaporates and then the temperature really goes up and the battery is toasted.
I plug in my CTEK MULTI US 3300 (CLICK) until it is charged, leave it for a day of pulse charges and then unplug it. I purchased mine from Canadian Tire when it was on sale for less than half the Amazon price shown.
That did not help my battery last year which died just as the two year 100% replacement warranty expired.
I used to open my old Varta and fill it with distilled water just to the bottom of the six fill holes, maintenance free it may have been but the electrolyte does evaporate little by little. When those plates are above the fluid level damage occurs and the full charge is not reached.
I keep that Varta as a one of two spares all charged up for emergencies, I should do as James 1549 says and hook her up to the car and see the amps when starting the car. It may be a boat anchor, not that we would heave it into the nearest lake these days.
Last edited by onehundred80; Jan 15, 2017 at 04:16 PM.