[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [New Search]
Had heard the one about concrete floors, hadn't heard the one about metal ones. Batteries undergo slow dicharge in idle conditions anyway, have never been sure how the material underneath it was supposed to affect it. Had heard one explanation involving submarine batteries(iused to work at a submarine yard), that the cold floor caused diffeing concentrations in the electrolyte and the difference in densities between the top and the bottom of the electrolyte next to the plates caused a small current to flow, eventaully causing discharge. It's a story, anyway. These were very large batteries, though, like 4'-6' tall. Most of your standard alternators require some current to flow through the field in order to generate AC current. The only ones I can think of that don't, use permanent magnets, like the old bicycle generators. So yes, you have to have a non-flat battery in order to get current out of one. No push starts with a totally flat battery. You probably couldn't with the newer vehicles, you can't start them in gear anyway, manual transmissions have interlocks to prevent it. Moot point. I suppose with the old generators you could build up enough speed to get enough current to light off the engine, but it would take a prolonged push or a very long hill. Have never tried it. Being a DC machine, the field iron has some residual magnetism and that can get things started generating. In fact, you're supposed to polarize the field on VW generators after disconnecting the battery for any length of time. On Tue, 2 Jun 1998 14:02:05 EDT, you wrote: >some stories that guys at work have told me. > >true or not? > >1. "don't put your battery on the ground (concrete, etc.) - that's the >quickest way to kill it" > >why would this be true? > >2. "don't put your battery on the metal floor (i.e. normal battery tray area) >of the car, that'll kill it" > >why would that be true? > >3. some guy was talking about "new cars" (a chevy truck, in particular) and >said that the alternator won't recharge the battery if it's flat, it only >"maintains" it. > >that i don't believe. > >and a question of my own: > >what tire pressures do any of you run on the front with stock wheels and >tires. 17/18psi seems a bit low to me, even though there's not much weight >there. > >sonny >