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Hi
For me it seems that the current limmiting circurit 1TR9 and 1TR10 is always on, or the Darlington Transistor 1IC4 is not working proper.
I would look for all 3 transistors maybe just put some new ones in, sometimes they mesured as good with a DMM but don’t work because of lack in HFE.
Important to control or renew is 1C23 (100uF). If this cap has not enough capacity it will put the curent limiting circurit on too fast so that the solenoid can’t engage.
Regular transistors will work e.g. BC 547 cost only a few cents.
Darlington should be at least a TIP125.
Let us know if you got any progress.
Kind regards
Christian