1979-1993 & 94 Conv [Subscribe to Daily Digest] |
over time batteries wear out.. every time u start your car (thrash the battery) a small quantity of the plate material ends up in the bottom of the cell.. in essence over time your battery loses its capacity.. it starts its life at say 75 amp hour.. but this gradually gets less as the plate material leaves the plates..
what fools folks is that the battery has enough in it to start the car.. they assume its okay.. but it isnt.. it has lost most iof its capacity and will go flat long before it should..
in extreme cases this plate material fills up the gap in the bottom of the cell and can short out the cell.. this can cause a dead cell or one that self discharges over night..
modern batteries are made as small and as light as possible.. the plates are very thin.. they produce a lot of cold start current but dont last long.. in essence they are like a donkey on steroids as opposed to a carthorse.. the answer is always to fit as bigger battery as u can.. the bigger the battery the less it dies each time to start your car..
there is a test called a black acid test... a heavy but short load is applied to the battery.. pretty much like what happens each time u start your car.. this stirs things up.. acid is then sucked up from the bottom of a cell.. if its greyish black.. the battery is worn out.. too many charge-discharge cycles is the technical term..
anyway its possible your friend has some major battery drain that is causing a good battery to go flat.. but its far more likely just to be a worn out battery.. a good 3 amps plus would be needed to flatten a good battery over night.. possible but unlikely..
to make sure put an ampmeter between battery terminal and lead.. see what it tells u..
trog100
posted by 62.254....
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