Batteries - Testing and charging

Da_Hose · Post by **Da_Hose** » Mon Jul 20, 2015 4:41 pm

I had to troubleshoot a charging issue and finally decided to replace my very old, low amperage charger as well as get a battery tester.

My new charger is a Black & Decker BC15BD. I bought it on Amazon for $50. It has multiple modes that test different battery types as well as your alternator . It also has a start function, although I have a portable battery that helps with that. I am very happy with it.

http://smile.amazon.com/gp/product/B00K ... ge_o01_s00

The battery tester I bought is a Solar BA5. It is AWESOME. Easy to use and will test any kind of battery. Price was good too. http://smile.amazon.com/gp/product/B001 ... ge_o01_s00

I relied on these testers to confirm that my alternator needed replacement and that my battery was still ok. With the new alternator in, the battery is holding above 12V. I am very happy with this little guy too.

Jose

dwcains · Post by **dwcains** » Mon Jul 20, 2015 6:16 pm

A fully-charged modern car battery should be just about 12.7 volts, but many of our older cars won't fully charge a new battery because the chemistry is different than it used to be and alternator output is usually less than 13.4 volts. One of the biggest improvements you can make is a voltage regulator with a higher voltage output. 14.5 volts will make almost all the cars' accessories function better, and it will also maintain the new battery better. I've been using these for maybe 15 years in my Alfa's and BMW's:

http://www.davebarton.com/AdjustableVoltage.html

Pod · Post by **Pod** » Thu Aug 13, 2015 9:32 am

dwcains wrote:I've been using these for maybe 15 years in my Alfa's and BMW's:

http://www.davebarton.com/AdjustableVoltage.html

I just looked at this site. Very interesting and educational! I think I need to try one of these.

Since the alternator is located well away from the exhaust, I don't reckon I need the external kit. Any comments please?

Brucey · Post by **Brucey** » Thu Aug 13, 2015 9:56 am

you can modify a standard voltage regulator to give a different fixed voltage or you can fit a different bosch PN (suitable for Volvos) that gives you the volts you need. (see previous threads)

I worry about anything with a trimming potentiometer under the bonnet; sooner or later it'll go intermittent and this could trash every ECU on the car. You have been warned.

BTW the voltage is only half the battle; the BMW electrics have a high parasitic draw; I just disconnect my battery when I'm not using the car for more than a couple of days. The present battery is now 8 years old and in rude health.

cheers

Pod · Post by **Pod** » Thu Aug 13, 2015 10:10 am

Thanks, Brucey!