402 Thunderbolt Int Spark

[vern99]

I have a 40 hp mid 70's 4

I have a 40 hp mid 70's 402 Merc. It wouldnt start the other day.... no spark .... left it about 2 hrs.. it fired right up. It did the very same thing yesterday. No spark/ spark / no spark/ spark... etc.
Any ideas ?

 

[fastjeff]

"Disconnect the orange kill wi

"Disconnect the orange kill wire and see if this problem goes away. If it does, look for a short in that wire somewhere.

Jeff"

 

[beckerjs]

"if you disconect the black/ye

"if you disconect the black/yellow wire on the switch box the ign will be hot all the time. This will tell you if its in the harness/key or if its engine/switchbor and trigger. The b/y wire should be split and also go to a mercry tilt switch boted to the exhaust, this grounds the ign when the engine is tilted up. More help here on merc specs http://www.maxrules.com/fixignitionspecs.html"

 

[beckerjs]

"Jeff says orange, I say b/y,

"Jeff says orange, I say b/y, depends on the year."

 

[fastjeff]

"And YOU are correct, sir. Th

"And YOU are correct, sir. The earlier ones used orange (which Merc calls "salmon").

Jeff"