Issue...

[spbinette]

Hey guys... I have been asking around and nobody seems to know the answer... I have a mercury 18xd and when i first put it in the water and after i let it warm up (2-4 minutes) i take off and it only has about half the power it usually does if that. After checking it out i realized only the top cyl. was firing. If i run it for about 10-15 minutes all of a sudden the bottom one kicks on and im tearing across the lake. Once this happens im ****en for the rest of the day. The motor doesn't skip, it's EXTREMELY responsive, and it pushes my boat perfectly... I have asked so many people and nobody seems to have the answer as to WHY does this happen and what do i need to do!?!?!?!

[jumpjg]

Sorry, I'm pretty green regarding Mercury details, but in sounds like the ignition on the problem cylinder is intermittent. If all electrical connections are clean & secure, I might try something easy like changing spark plugs.

Best I can do for now.

Joe in St Louis