Hi all. This is my first post as a result of my first pinball machine purchase. I picked up a 1975 Bally machine called "Bow and Arrow". The machine is in fantastic condition. The back glass is perfect, plastic is flawless and playfield looks great. However it does have an issue while playing it. The 100 point scoring (reel?) for player #1 will run continuously. It does stop after a while but at some point will just start running again. I really need to fix it despite how much it helps my already horrific scores. I've watched the game when someone else plays to see what triggers these events. I thought maybe one particular switch that awarded points might be sticking but it's not one switch that does it. These events are initiated from random switches in the playfield which leads me to believe the issue is most likely in the scoring reel itself.
I pulled the back panel off and identified the solenoid behind the Player #1 100 point counter. I was going to take a stab at ordering the part and replacing it but thought maybe I should start here first. Anyone experienced the same issue or just have some good advice before starting? I am completely new to this and want to proceed cautiously. Thanks in advance for any help.

Well I was wrong but I really enjoyed taking out the scoring reels and cleaning them. It made the machine slightly less intimidating.
That was fun and I intend on getting more experience.
I tested the machine after cleaning the scoring reel and the issue persisted. Even worse, I tried more than one player and the problem transferred from player 1 to 2 and to 3 when it was during an event but the previous player turn ended. Clearly I was wrong about the issue being in the reel. Something else is sending the signal to the reel because it continued as players turns changed.
I am noticing the events are shorter and less frequent the longer the machine is on. Any other suggestions?
I’m leaning on hiring someone to repair this issue and give the pinball a look over. I’m hoping they will give me some pointers if I do hire someone to repair it.

Yes it does. When the machine is cold, it will always start as soon as I initiate the first game and the first ball is loaded into the shooter alley. It runs almost continuously and will occasionally stop after the machine has been running for 5 or 10 minutes but it's almost constant. I will also add that after the first game it may not start as soon as I start the subsequent games. If it doesn't start at the start of a new game, it absolutely will as soon as the ball exits the shooter alley and trips one of the 500 point switches after the ball gate.
In summary, it always starts these 100 point continuous scoring events at the beginning of a game. Sometimes it's when the new game button is selected but mostly after the ball trips a 500 point switch. I hope that made sense and thank you for looking at this issue. I've ordered cleaning supplies and basic maintenance parts. I've decided I'm going to try to tackle this on my own and will call in the experts if I can't get it.

Problem solved! Turns out a small screw fell and landed on the 500 point relay. The switch should be normally open but the screw bridged the connection. I cant thank you all enough for your help. I needed some direction for my first pinball repair. Well... repair is a bit of a stretch considering the real issue.

This machine works flawlessly. I feel it was a real bargain at $500 especially with the playfield and back glass in excellent condition. I've ordered cleaning supplies, bulbs, rubbers, etc. I'm going to go through it to make sure it is properly maintained. I also want to try to speed up the gameplay a little bit.

I think I'm officially hooked. I'm having a blast with this pinball. Thank you again!