KEM 496 burning port side spark plug wires
I had this motor put in in 2006 (Anchorage). It has been burning spark plug wire since day one. I have tried different mechanics,8mml wires, wrapping wires with heat wrap, changing up plugs and gaps. Has anyone every experienced this situation before or maybe have another direction to look? The boat has never left me stranded, I just always return with burnt wires either arched out at the boot or cylinders 5 and 7 wires burnt completely in half. The starboard side cylinders never burn. Any help would be appreciated.
1969 Tollycraft 24 ft
alpha one outdrive
KEM 496 motor
Possible exhaust manifold leak?
Check manifold for cracks if none replace exhaust manifold gasket.
If you're burning both #5 and #7 plugwires concentrate on the #5 cylinder exhaust port.
Hopefully that will resolve your problem.
You might want to contact sport drifter on here a she has been running that motor for a bit in his river boats.
I am sure you checked this but are your plug wires laying on or close to the exhaust manifold if so that will burn them. As will an exhaust leak in that area like DRIFTER_016 pointed out.
Have you felt the exhaust manifold in that area while running to see if it is hotter than the other areas? If so you could have a blockage in it not allowing the water to properly cool it down.