Cold Misfire

[Cape Coder]

I have a 1985 60 HP Merc that misfires at med to high speeds when it's cold. If I run it at idle for a while then accelerate it runs fine????

 

[Laddies]

Re: Cold Misfire

That sounds kind of typical of a switchbox that is starting to fail

 

[Cape Coder]

Re: Cold Misfire

Is a switch box easy to replace?

 

[Laddies]

Re: Cold Misfire

Yes

 

[Cape Coder]

Re: Cold Misfire

TY for your help

 

[Cape Coder]

Re: Cold Misfire

While inspecting switch box I found an exposed wire from switch box to trigger assembly and an exposed wire from switch box to one of the coils. I replaced trigger assembly, stator (while I was at it) and wire to coil. Test ran it in the bay and it did the same thing, seems to run on 2 cylinders at WOT then after it warms up the other one kicks in. Compression on all cylinders is good. I'm waiting for a new switch box hopefully it will do.