[ngoma]

Sorry no cutaway photos, hope the description helps.

Cold start device works counterintuitively. Narrow silver piston faces to the rear. It retracts (forward) into the brass housing when cold. The strong springs in the metal (aluminum?) housing will pull the cable forward (further into the housing) which pulls the lever forward into advance position. So if the wax stat fails (fails to extend with sufficient heat), the strong springs will keep the cable tensioned and lever in advance position.

Circulating hot coolant heats up the brass cylinder which makes the piston extend, overcoming the strong spring tension, allowing the cable to extend rearward which allows the advance lever to move rearward into non-advance position.

Replacing the wax stat is HARD! Those springs are fighting you the whole time. DIFFICULT to get the two halves of the housing together; the springs force them apart with great force. I don't see how there could be any play in the cable at that end.

There CAN be some slack at the advance lever end, only when hot. The wax stat can extend far enough so that enough cable gets extended in excess of movement range of the advance lever to its stop.

This is undesirable because engine vibration makes the heavy cable end (the clamp barrel on the end of the cable) vibrate freely which can eventually cause individual cable strands to break. Best to get the engine well hot, verify the advance lever is at its stop, and quickly take up the slack so that the cable end can't flop around. IOW, the cable is SLIGHTLY under slight tension when hot.

How do you know the wax stat is good? Did you test it? Easy in a small pot of hot water and cooking thermometer.