New to me 1500 Merc 1973 vintage. Turns over fine and gives a spark when the key is turned and when its turn off but nothing while cranking. Ive got a shop manual on its way but wont be for a few days yet. 363XXXX serial number. Ive seen a reference to a mercury switch but I checked continuity up and down and thats fine. No dead man lanyard on the controller that I can find. Any ideas where to start?