Small Engines (Lawn Mowers, etc.): pull cord on craftsman 20 mower replacemtn, phillips screw, lawn mower

Question
MOdel 917380200, serial#033833 .... I removed the pull cord housing, flipped it over and found a large phillips screw holding in the "spring", which is encased in a 2"diameter metal housing.  I'm curious to know what will happen to the spring when I remove this housing, and if there is a trick to keeping it from coming unwound.
Thanks.

Answer
If all the tension is removed from the spring it should not unwind.  Check out this web site  http://www.lawn-mower-shop.com/trstrt.htm

The starter is pretty much the same except you have a screw rather than a pin.  The pins used to be used instead of the screw.

Let me know if this helps.
Eric