minuteman62-64
Lieutenant
- Joined
- Apr 12, 2011
- Messages
- 1,350
Now that I've got (at least for now) the cooling issues resolved with my '82 Mariner I'm looking at another issue.
Motor is 30HP Mariner 30A, CD ignition, 2 cylinder, single carb and relatively new (about 30 hours) plugs. No. 1 (upper) cylinder plug seems to look like it should (light tan deposits on insulator). No. 2 (lower) cylinder plug has black deposits on insulator.
Based on my reading, #2 cylinder is running rich - maybe weak spark from bad coil winding. Is this correct?
How do I test? My shop manual has test procedures but they are based on a "Mercury Ignition Tester" which I don't have. I do have one of those gap type spark testers and a volt/ohm meter.
Replacement coils for this motor are kind of expensive ($256 for OEM) so I don't want to just go buy one on the chance that it will fix things. Or, is it a big enough problem to worry about? The motor in present condition produces plenty of power for my style of boating.
See photos. #1 is top cylinder and #2 is bottom cylinder.
Motor is 30HP Mariner 30A, CD ignition, 2 cylinder, single carb and relatively new (about 30 hours) plugs. No. 1 (upper) cylinder plug seems to look like it should (light tan deposits on insulator). No. 2 (lower) cylinder plug has black deposits on insulator.
Based on my reading, #2 cylinder is running rich - maybe weak spark from bad coil winding. Is this correct?
How do I test? My shop manual has test procedures but they are based on a "Mercury Ignition Tester" which I don't have. I do have one of those gap type spark testers and a volt/ohm meter.
Replacement coils for this motor are kind of expensive ($256 for OEM) so I don't want to just go buy one on the chance that it will fix things. Or, is it a big enough problem to worry about? The motor in present condition produces plenty of power for my style of boating.
See photos. #1 is top cylinder and #2 is bottom cylinder.