Posts: 3508
Location: Elk River, Minnesota | Hiya,
As stated, I would start with something easy and is more preventative maintenance than anything... Change the plugs and test the motor out. QL78YC I believe will be the number on those from Champion. I also would suggest replacing the fuel filter on the engine as well. that should be on the right side of the engine as you are looking at it from the front.
I would also agree with doing a Decarbonization of the motor as well. Not sure if that year motor has a hook-up for it or not, so I'll try to describe what it looks like and where. Behind the carbs on the left hand side of the motor there might be a little red tab and a gray cover over the tip. Under that cover is what looks like a tire valve stem, which will accept a spray tube that attaches to a can of fogging oil or decarbonizer. Not all former OMC dealers have the nozzle anymore, but I would think you can find them on ebay or just call around...
After decarbonizing, take it out and really run it clean. Word of caution, though...you may want another set of new plugs as after decarbonizing, you may be blowing a bunch of gunk out of the powerhead, thus fouling a plug or two. I just got done doing that to my brother-in-law's johnson 50hp 3 cyl (same block as yours) and we fouled two sets before it ran clean.
If neither of these take care of the issue, then I would start looking at a carb rebuild.
In most cases like this, the issue is usually not electrical (outside of a fouling plug) as it is somewhat intermittent. With most other electrical components (coils most notably) go bad and stay bad from what I have experienced.
That engine is a great engine...I'm betting the top items here will solve your issue.
Steve |
