I need to check the spark plug on my 16.5 hp. Craftsman lawn tractor (bought in 1999). I have had someone do the work for me in the past but no one nearby does mowers anymore. My question is (okay, don't laugh) where is the spark plug located? I can't find it in the manual.

Here's what happened... I was mowing and suddenly something made a pop (like a small backfire) and I lost power. It refused to turn over. I pushed it into the shade and took a break. When I came back out I was able to get it going but it failed again 10 minutes into mowing. This time no amount of resting the machine worked. So I checked the air filter and oil. The gas was fresh and the same I had used earlier in the week. I called my brother (1500 miles away) and he said to check the spark plug. That would work except I don't know where it as and it is not located in an obvious location.

Any help would be greatly appreciated.

Lift the hood. The plug should be on top of the engine. There will be a black wire attached to the plug that must be pulled off before the plug can be removed