1994 mercury 40 HP30 JET model

[jsmilliken]

Last Friday i took the boat out everything was fine, found one nice fishing hole. Saturday morning went back out to try it again and found out boat couldn't go faster then 17 mpg, before it would get up to 27 mpg. After taking the longer then usual traveling time to get to and from i went home thinking it would be an easy fix. Spent some time going over it last week, installed a new fuel line, new plugs, changed lower oil and even put new premium fuel in the tank. Hoping that would fix my problem i called a good buddy and we headed of to the lake Friday after we were done work. So we get the boat into the water, let it idle for about 5 minutes while we are getting our game plan figured out and off we go. 17 MPH is all we can get again, no change. So Saturday we start looking again. After checking multiple things on the motor, we find that the top cylinder is not firing . switched out the coil with the one below it and nothing. there is no power going to the coil from the SWITCH BOX ASSEMBLY. The lower 3 cylinders all work. The stater seems to be reading good.


My question is do i need a new switch box assembly or is something else the problem?

thanks for your help in advance