Re: reloading pull cord on 7.5hp
If the rope broke when being pulled, it will wreck the spring as it backlashes. So 1st is to check the spring.
Then, see the little 1/8" hole in the rope pulley? Find a pin or nail or something that will fit through that hole.
Now wind the spring up all the way, and back it off one complete turn. Stick the nail through the hole and it will keep the pulley from rewinding. Now at your liesure, feed the rope in. Be sure it goes behind the roll pin in the pulley (not the nail). Put the handle on the rope. Then hang onto it as you remove the nail and let the rope retract.
Do NOT let the pulley get away from you while you are winding it up, or there goes another spring!!!!
All this assumes you have a 1950 vintage 7.5. Very early 7.5s had a wire core rope with a hook on the end. They don't like plain nylon ropes but that is about all you can get.