Reminds me of when I decided to stay after work one day and clean the starter motor on my car, it would stick once or twice a week.
After cleaning it I managed to drop it on the floor, and the solenoid top with the electrical connections broke off
Not being able to get a replacement I decided to repair it with cable ties, thinking it would only have to work for 2 days till I could get another.
It would have to take a good thump when the solenoid kicked in, and would have to make a good electrical connection.
That was 4 years ago and its still going strong