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Purdy Swoft · 06-25-2014, 11:26 PM

Joe, I think that you still may not have the rotor tip set right in relation to direction of rotational backlash. Go back and remove all of the spark plugs so that you don't have to fight compression. Turn the engine untill you find the timing mark. Now look at where the rotor tip is pointing . Is it pointing exactly like Tom W s picture ? Grasp the rotor and see if it will rotate even the slightest amount in the clockwise direction . If the rotor, rotated at all in the clockwise direction, this will be a large part of the problem. There should be no rotational movement in the clockwise direction after the cam screw is tightened , with the trailing edge of the rotor tip pointing exactly as in Toms pic. Any rotationial movement in the counterclockwise direction won't matter and will have no effect on timing. Think about it like this. The distributor turns in the counter clockwise direction when the engine runs. this means that the distributor shaft is riding on the clockwise end of the backlash. If clockwise backlash remains after the cam screw is tightened, the engine will have to turn to catch up the slack before the shaft of the distributor could begin to move. This would throw off the timing. A person really needs to understand this and be able to adjust out the backlash in the correct direction so as to be able to properly set the timing. I would also check points gap on each lobe of the points cam. A bad points cam won't run good no matter what. I would also check air gap between the rotor tip at each contact in the distributor cap. All of these gaps need to be as close as possible to the same. Some say use a .025 gap. I use a gap of .035 for stronger spark. If the gaps at the rotor tip are to small or uneven, some cylinders will be getting weaker spark than others. This can effect idle and not give full power. If the points don't measure pretty close to the same gap, on each lobe of the cam, you can't expect proper performance. Not trying to be a smartazz, It can't hurt to check, maybe you will find something that will help .

06-25-2014, 11:26 PM	#17
Purdy Swoft Senior Member Join Date: May 2010 Location: Alabama Posts: 8,099	Re: Old Points or Modern Points Joe, I think that you still may not have the rotor tip set right in relation to direction of rotational backlash. Go back and remove all of the spark plugs so that you don't have to fight compression. Turn the engine untill you find the timing mark. Now look at where the rotor tip is pointing . Is it pointing exactly like Tom W s picture ? Grasp the rotor and see if it will rotate even the slightest amount in the clockwise direction . If the rotor, rotated at all in the clockwise direction, this will be a large part of the problem. There should be no rotational movement in the clockwise direction after the cam screw is tightened , with the trailing edge of the rotor tip pointing exactly as in Toms pic. Any rotationial movement in the counterclockwise direction won't matter and will have no effect on timing. Think about it like this. The distributor turns in the counter clockwise direction when the engine runs. this means that the distributor shaft is riding on the clockwise end of the backlash. If clockwise backlash remains after the cam screw is tightened, the engine will have to turn to catch up the slack before the shaft of the distributor could begin to move. This would throw off the timing. A person really needs to understand this and be able to adjust out the backlash in the correct direction so as to be able to properly set the timing. I would also check points gap on each lobe of the points cam. A bad points cam won't run good no matter what. I would also check air gap between the rotor tip at each contact in the distributor cap. All of these gaps need to be as close as possible to the same. Some say use a .025 gap. I use a gap of .035 for stronger spark. If the gaps at the rotor tip are to small or uneven, some cylinders will be getting weaker spark than others. This can effect idle and not give full power. If the points don't measure pretty close to the same gap, on each lobe of the cam, you can't expect proper performance. Not trying to be a smartazz, It can't hurt to check, maybe you will find something that will help .