I've been having fun with this and wondered what your take on it is.
Vw T25 1987 Diesel 1.7
OK, Friday night I left sidelights on by accident, noticed after a few hours, went out started 'Val' up and reparked her and doubled checked all was off.
Next day, went to drive to my folks to fit replacement fuel tank with my bro and the van wouldn't turn over.
I had radio, head lights and ignition and battery lights.
I thought maybe the side lights and starting and stopping the engine the previous night had flettened it.
Anyway, ma and pa came over towed me 50metres down the road and we bump started her.
Drove 4 miles to folks house, parked in drive ready for fuel tank job. turned engine on and off 2 times to check it was ok.
Swapped fuel tank Saturday/Sunday - that was interesting!
Went to start the van to take it off the ramps and same problem as Saturday morning. dash lights but no starter motor.
Ok - elimination time.
Spare ignition key to check ignition solenoid - no difference
Check battery power - fully charged
My bro by passed starter solenoid and starter turned over.

Checked forums and peeps hinted at dirty solenoids and sticky solenoids.
Extracted start motor and noticed power cable was partially split - so recut and crimped that.
Wire brushed starter motor to eliminate shortages.
reassembled starter motor.
= nothing.
Now we can't even achieve the by-passing trick from earlier.
Sorry its a long one but the background might help pinpoint the issue.
At the moment we're thinking new starter motor and solenoid as the two appear to come together as one.
If there're any members in the portsmouth/havant area with a spare starter for me to try I'd appreciate it.
I'd even have one collected anywhere in the UK and sent back if anyone out there is willing to trust me? It's worth a test before spending £100 on a new starter.
Thanks
Darrell