XPost: alt.home.repair, sci.electronics.repair   
   From: michael.trew@att.net   
      
   On 1/30/2023 16:42, Carlos E.R. wrote:   
   > On 2023-01-19 02:01, Rod Speed wrote:   
   >> On Thu, 19 Jan 2023 04:54:10 +1100, John Robertson    
   >> wrote:   
   >>>   
   >>> After the engine starts, then disconnect the negative lead that is   
   >>> AWAY FROM THE BATTERY so any spark created at the disconnect point is   
   >>> unlikely to cause the battery to explode if hydrogen gas was created.   
   >>   
   >> No, because the battery doesn't gas unless it is being charged when   
   >> fully charged already and that won't be happening with either battery.   
   >   
   > The "bad" battery will start charging when connected, and there will be   
   > no current limiting.   
      
   The last time I had a really flat battery, and jumping it didn't work   
   (perhaps the cables weren't heavy enough gauge), I started it with   
   another battery installed (cables semi-tight pushed-on)... then with the   
   alternator keeping it going, I disconnected that battery, and hooked up   
   the flat battery.  You could instantly hear the engine bog down from the   
   alternator kicking into high-gear.  This was a 1960's car, BTW, with a   
   modern 12v battery.   Perhaps this isn't the hottest idea with a new car   
   using expensive electronics, but it works fine on older rigs with a good   
   alternator.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)