hi there i have a 02 plate range rover vouge i have had 2 fit a new starter motor on it at the weekend and battery the battery is going flat after 7 days i have put a volt meter on the car it has a volt drop of half an amp removed neg battery lead and put a meter from battery lead 2 battery termail and its reading half an amp

 

You may just need a new battery. It is normal to have some amp draw when the vehicle is off. Mine does and can go for a couple of weeks without being driven. I have noticed that when my battery does die from leaving something such as a map light on, it takes a lot longer to recharge the battery while driving than it takes with other vehicles I have owned. I think this is because the LR alternator does not put out as much voltage as most other alternators.

 

.5 amp and under is considered normal for parasitic draw. Most vehicles draw less unless there are aftermarket accessories installed (stereo, alarm, tracking, etc.) I haven't tested my Rover's but my 05 Mercedes was drawing .3A when I had to check once. I agree, you may need a new battery. If the battery went through deep discharge some time during the starter install, it's a good chance it has affected its ability to hold a charge. Car batteries (except deep cycle batteries) can't handle being discharged too many times. Some newer batteries will fail after 4 or 5 discharges. Older batteries can die after 1 discharge.

Just for kicks, maybe test the alternator with your voltmeter. With probes to the terminals and engine running, you should get at least 14.0 volts. 13.5 to 13.99 would be weak. Anything under 13.5 warrants replacement. As for battery testing, you'd have to get a tester that perfroms a load test. It basically applies a heavy load to a full charged the battery (at least 12V) with engine off, for about 10 seconds. If the voltage during the load test drops under a certain voltage, it's deemed to be weak/bad.