Spin start
There are two models of spin start and you have to go to the Northern site, and in their catalog they sell them. One model does use a spring, but the model I have does not. My system you just put a cup on the top end of the crankshaft, torqued down, and then another mating piece in your drill. Just type in NorthernTool.com and then spinstart. The models will come up. I put pics of the system on trailer sailor, so you could see how it works. From what I can see the spinstart system can be adapted to all models of outboards, as well as lawnmowers, both riding and pushing! It is easy!