To advance timer, take off security nut, take 4 screws off back, and top will slide forward. It you get to timer shaft, you can manually advance it by turning timer. Pain in the ass to go through all that. The start timer works likes this. there are numbers on the start mechanism. You position the white arm on the number of coin throws you want to start. For example, if it is on two, it would take two coin pushes to start machine. If you had a 75 cent coin slide, then it would take 1:50 to start. As it goes around, you can push the start button to start machine. When the metal arm is raised up by the white raised coin selector, the start timer stops. I have an apartment owner that owns about 10 of these. Hate doing the bellows on these, especially if you don't have alot of room to work. Most of time, you get stuff jammed into coin boot. Have to clean out or put in new pump.