[W126 Coupe] Back to the battery drain issue

[jralex at ix.netcom.com]

Since we are quessing. Mine would be a bad battery with an internal short or bad cell. I had a new MB battery in a car that was not often driven and seemed to drain rapidly even after a full charge with power charger. An underchaged or overcharged battery wil sulfate. Sufate happens when the sulfuric acid(eletrolyte) is not excited often enough and deposits on the lead plates reducing it's cranking capacity. Enough bridging especially on + - adjacent cells with short the unit. I got OK reading from meters and float ball tests. When I used a Refractory to measure specific gravity of each cell I found one cell way below the others indicating a bad(generic) battery. I now use a Battery Minder by VDC with a circuit that float charges at 1 amp and then goes into a mode of millivolt pulses that will actually de-sulfate by the continuous pulsing the sufate breaks loose and is resoluablized into the sulfuric acid. There is a lot of supporting data by the likes of Popular Mechanics and others to support it's effectiveness. Even bringing old bad batteries back to service. If you don't have nearby electrical outlet or not want to keep a drop cord in your way on a continually basis they have a photoelectric cell unit. Many people use these on farms and sailboats. A battery that is used everyday will last about four years but cars not used but for weekend, 'SundayGotomeeting' cars are good for two years or less. The VDC unit will change that status. I payed about $50 for my 110v unit and the photocell units run about $100. They pay for themselves. I bought mine at Northern Tool and saw the photovoltaic unit at Batteries Plus. Later, Jim Alexander

-----Original Message-----
>From: Vance Rowley <vance.rowley at tiscali.co.uk>
>Sent: Feb 4, 2006 11:20 AM
>To: mbcoupes at mbcoupes.com
>Subject: [W126 Coupe] Back to the battery drain issue
>
>Well unfortunately, although all evidence pointed to the vacuum pump as the cause of this intermittent 6amp current draw. I have had power to the pump disconnected for over a week now. It just so happens I haven't used the car for this last week, so was a good opportunity to see if the battery would be OK or not. Well, you guessed it, the battery was almost dead. Certainly not enough power to start the car anyway. Just a few small cranks of the engine.
>
>So, has anyone any ideas what else could draw around 6amps for between 30 and 60 secs every 5 to 10 minutes or so?
>The 5 year mystery still unsolved as yet.
>
>Cheers,
>
>Vance.
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