I have an 1986 mini which sees to have a drain when trying to start.With the battery in the boot as normal when starting by the key she wont start untill I just start to let the key go ,I could sit all day trying to start it and nothing .If I put the battery at the front and use jump leads and run a wire to the coil for power and jump the starter she starts straight away .I have changed the starter and still the same (twice).Anyone got any ideas.
Thanks in advance
Should be a ballasted ignition system, which means there will be a ballast byepass wire running to the coil specifically for starting.
Check the coil see if theres 2 wires running to the positive, think its white/yellow the byepass wire, should go to the solenoid, make sure its getting a voltage to it.