from what i know most hoppers hold an average of $400-$500
Which would be 1600 to 2000 quarters. My guess is most home owners only partly fill the hopper, or they use tokens in place of quarters to cut down on losses from friends & family taking some from the machine.
To test your hopper put some quarters in it, maybe 25 or more. With the door open and machine powered on press & release the "TEST" button on your mpu tray until you see the front display show "04 d". This is the TEST step for the hopper test. The hopper should run and payout exactly 10 coins. Press the "Change" button to repeat the test. Close the door or press the "Reset" button to exit the test menu system. See image with hopper test instructions below.
Since your Diamond Line machine is working let's end this discussion topic, it is getting kinda long. If you have other questions about it, or about the other machine, please start a new topic.
To do that just go to the Bally S5500 area (link below) and then click on the blue button near the main menu buttons that says "New Topic" to start a new discussion. Thank you.
Bally Reel Games, including S5500 machines:
http://newlifegames.com/nlg/index.php?board=75.0