I have my pull cord replacement installed and see how there are flange arms that extend to engage the motor shaft. When I test it the cord does not retract back into the pull reel. I cannot find any spring to retract the cord. It is a Tecumsah engine I think, and it is about 8 years old and still works great.
The spring - a large coil one - lurks beneath the cord winding spool. To get some tension, wind the cord around the spool until you can feel spring resistance. The end of the cord is then pushed through the hole in the housing, through the pull handle and knotted. Takes loads of practice, but once you've done it.....!
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