Before you get charged up to change the timer look at your
coin acceptor. What kind of
coin acceptor are you using? If your using a mechanical
coin acceptor you could have someone who has tried to flip the cherry switch inside the vacuum though the
coin return. Also test your timer to see if you can pulse the timer with a jumper wire between the terminals where the
coin acceptor connects to the timer. Also check to be sure your timer dip switches are still set where they are supposed to be. I had someone open my faceplate on a couple of my vacuums and change the dip switch settings. If you want your timer to last almost forever, install a mercury relay that is controlled by the vac timer, this takes the motor load off the timer.