battery charging

- R
- richard
  
  Contact options for registered users
posted
17 years ago

Fri, Sep 8, 2006 8:25 PM

On a RR, the battery slowly loses charge. I'm struggling to understand if it's the battery (which has tested fine) or the charging.

Initially I was puzzled because it mainly discharged on longer trips (over 250 miles and it would start to fail) yet on short frequent runs it seemed to be charging and holding charge fine.

I had to charge it overnight with a 4 amp charger and next day it would be OK - this was done weekly. A week of short trips and it needed some help, but one long trip and it was struggling.

I'm prepared to accept that maybe on the longer run more current is drawn then the cumulative effect of a weeks worth of short trips, but why does a mains charger actually charge the battery when the car itself won't?

I'm now starting to question if it's the battery or the alternator.....

- D
- Derek
  
  Contact options for registered users
Vote on answer
posted
17 years ago

Fri, Sep 8, 2006 9:07 PM

I'm sure if you get a weeks running then the battery it is holding its charge you are losing charge because the alternator is not putting enough in to maintain the charge easy way is to have a word at a reconditioners they can easily check the output of alternator with a collar type ammeter. I'd be inclined to suspect the Diode pack on the alternator is giving trouble or it could be something as simple as the drive belt slipping or even worn brushes and as I keep banging on about the quality of the connectors on land Rover kit clean the terminals they do give trouble regularly Derek

- L
- Lee_D
  
  Contact options for registered users
Vote on answer
posted
17 years ago

Fri, Sep 8, 2006 11:33 PM

Derek uttered summat worrerz funny about:

Kick it up and see what voltage you get at the battery with the Engine running.

Around 14 Volts is a good sign. Then check it after it's been stood and the engine is cool... then again , check it in the opposite order. If your owt like me by the time you fight a path to the garage to the multimeter, then find out it's not where it should be , then trash a bit more garage and find it , well the engine wil be cool regardless ;-)

Lee D