1975 7.5hp mercury no spark

Outboard Mike

Seaman
Joined
Apr 26, 2009
Messages
55
I have a 75 7.5 hp Serial #4555695 with a no spark condition. I have completed the troubleshooting test off of the mercury manual and everything seems to point to the switch box. When I disconnected the orange stop wire still no spark. The coils test out at 1700 resistance which is to spec. The HT to ground tests at 1100. The Brown trigger wires test out at 133(140-160 is the spec). (The digital meter I'm using is probably not good enough to determine the 133 Is out of spec). Is there anyway to test the switch box before I spend $200 on it.
 
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Outboard Mike

Seaman
Joined
Apr 26, 2009
Messages
55
Re: 1975 7.5hp mercury no spark

I retested the trigger wires with another meter and the reading was 145(in spec). The other readings were pretty much the same. Any ideas on additional tests would be appreciated.
 
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