Is there a troubleshooting method for a 40hp, Mercury. It's a 1978 402 model 40 HP <br />2 cylinder S/N 5042254. <br />The problem is no fire to plugs! <br />I've been told it's either the power pack <br />#3324911 or the individual coils. <br />Is there a way to test the power pack? <br />Say...