E30 draining battery

[Colin <sasha@xxxxxxxxxx>]

My E30 318i has been hard to start in the mornings for a while now.
Id turn the key to start and all i could here was the solenoid on the
started clicking. After about 10 secs or sometimes playing with
connections it would only start then. 

Last night i disconnected the battery and reconnected it this morning
and the car started STRAIGHT AWAY. This obviously looks as though
something in the car is draining the battery overnight, this is also
backed up because in the mornings when it was hard to start, once it
did, the alternator charged the battery and it would start straight away
hours.
Has anyone had a similar experience??
I also have a new battery/starter/alternator
My car has an alarm fitted but i have had this for over 3 yrs with no
previous probs.
TIA
Michael St.Clair
1984 318i (2 litre)

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