The car is a 1988 340 vario with 1.4 engine
The starter engine is original Valeo/Paris-Rhone
'PARIS-RHONE
FRANCE
D 9 E 12V'.
As an alternative I have an iskra 11.130.590.
Only 1 in the car

I unmounted the starter, cleaned it, oiled with light oil, and ON THE BENCH it works fine when connected to a spare
car battery (fully loaded); when the cableshoe vane on the back of the solenoid is additionally connected tot the +
(mimicking the turn of the ignition key, the pignon shoots to the nose of the starter and turns fast.
This LOOKS GOOD TO ME.
But: after mounting the starter in the car in the correct position (is fail-safe) and connected to +, - and ignition-lock wire on the vane
(green-blue thin wire) and turning the key: the starter motor spins full speed, but the pignon does NOT engage the teeth on the flywheel.......!!!!!!!!!!
Every now and then, the pignon will enter the flywheel tooth-ring and the engine will start....
BUT THAT IS NOT THE WAY IT SHOULD BE.
Anyone of the forum members who can solve this mystery for me??
Help is urgently needed, as the car is my daily (should be my daily).
Note: both starters don't give a happy starting engine, the Iskra is described above, the Valeo's pignon seems to collide with the sides of the gear-ring, making horrible noises.... NOT GOOD EITHER..
Thank you,
oldscoolcart