timing a motor
2 Answers
try this This is the way I do it. Put the cap on the dist. Make a mark on the housing that lines up with #1, (Scratch mark or Sharpie), pull the cap back off, line up the rotor with your mark. Now look at the other end of the distributor, pick a groove between two teeth, and mark the housing there. Now, rotate the shaft counterclockwise (from the top) till the bottom of that groove is lined up with your mark on the bottom of the housing. You could mark the distributor at the top again in case it gets disturbed in the process of dropping it in. Make sure your motor is not only on TDC, but put the timing mark on whatever you want your initial timing to be, let's say 12° for instance. So, now the motor is sitting with the timing mark at 12° BTDC, and your distributor shaft is about a 1/16th of a turn before that, so it will rotate into position as it drops down and engages with the cam. Once it goes down till it's sitting on top of the oil pump shaft, there will be about a 3/8" gap between the mounting flange and the intake surface. If all your marks are pretty close to lined up, push down slightly on the distributor, (not hard, don't force it), and have somebody bump the key till it drops all the way. If you want to check yourself, or make sure it will fire the first time, bump the balancer on back around to 12° BTDC again and make sure your rotor still lines up with your #1 cylinder mark. If it doesn't pull it out and repeat. When your marks line up like they should, go ahead and turn the distributor housing to line up your #1 mark with the rotor, install the distributor clamp and snug it down, put the cap on and connect the wires, because it WILL fire the first time, and be within 2° or 3° of your target initial timing.