1986 Evinrude 60 HP misfire

[Fl Bob]

Need some help on where to start checking things and what are the most likely causes of a lower RPM misfire. The engine starts fine though seems to idle a bit low, when put in gear there is a misfire that continues till about 2000 RPM then smooths out and runs great. No problem getting to a plane quickly but the low speed misfire is troublesome in a low speed area. Any help would be greatly appreciated as I have no history on this motor.

Thanks, Bob

 

[jonesg]

Re: 1986 Evinrude 60 HP misfire

If you don't already own these tools go to autozone and get them
Compression guage and adjustable spark GAP tester.

Do a compression test with all plugs out , write the numbers down,

and set the gap tester to 3/8th inch gap,
see if spark jumps the gap and is blue not yellow.
Post results back.

Also a timing light will help in finding a dead coil whilst its idling rough.
Should cost you less than $60 for the 3 tools.

 

[Fl Bob]

Re: 1986 Evinrude 60 HP misfire

OK, since I was last on here I took the boat out again. This time I lost a cylinder completely when it was in the water. I have checked the spark and it is good, I also checked the compression and it was also good with 120# on 2 cyl's. and 113# on the third.
Any suggestions on what to try next?

 

[jonesg]

Re: 1986 Evinrude 60 HP misfire

Same again.
If the timing light doesn't show it dropping a coil its probably a clogged carb.