Annoying battery drain

[tone]

T25 2.1 1989. I'm still trying to find the cause of a battery drain - my van is used once or twice a week - usually it starts first time but if left for 5 days or so the battery goes almost flat - just half an hour on a charger will start it again straightaway - almost new battery - had it checked along with alternator and everthing is fine. I've double checked that nothing is left on - if I disconnect the main battery when not in use it will fire up first time even after 2 weeks so it must be draining somewhere - just baffling where - the cd/radio is live wired but as it's off when not in use it can't be this = there is no alarm so the only thing live is the clock - we've had the van for years and until about a year ago it would have started first time even after being sorned for months .My daughter had the same problem with her T2 and it turned out to be a knackered leisure battery - once she had disconnected this it was fine - my leisure battery is never used and must be 15 years old - I have a spare starter battery that I can exchange it for - will this be ok to use this as a leisure battery and could it be causing the problem ? I also found that the 35amp fuse on this battery was blown anyway so I can change this - I don't have a meter but is there any other thing I can do to identify the problem without the hassle of taking it to a garage .

Thanks in anticipation

[Oldiebut goodie]

Get a multimeter - they are dirt cheap for what you want to use it for. It will be difficult tracing it without (yes, you can do it by other means but with a meter it is easy).

[tone]

Happy to get one but how do you use it - through the fuse box ? As you can see I'm not technically gifted

[Ralf85]

This helpful video explains how to do it

http://youtu.be/KF1gijj03_0" onclick="window.open(this.href);return false;