QuestionI'm helping a nieghbor try and get his mower running. It was gifted to him. Since he has had it, it has progressivly run worse and now does not start. I am a automotive tech and have good knowledge of four strock engines.
What I can tell you is that it has spark and fuel.
Seems to be out of time. Is there a way to check the timing or is it indexed by a key that can sheer? Viewing inside the combustion chamber, lining up the pick up with the flywheel magnet. I rotated the flywheel until the piston was @ TDC. the difference was about 75-80 degrees. Any advise would be appreciated.
AnswerHi Eric,
First be sure that the ENGINE is getting fuel, not just the carb. Try squirting fuel or starting fluid into the carb's intake to see if you can start it and keep it running while adding fuel. If that helps, then the carb has a fuel flow problem.
If it quit right after striking an object, I could almost guarantee that the flywheel key is sheared and as you suspect, the timing would then be off. The flywheel is located under the recoil/cooling shroud. Its' bore is tapered and mates with the tapered crankshaft. The keyway in the flywheel and shaft keeps it from spinning on the shaft. A nut secures it. Use an impact wrench on the nut or a strap on the flywheel. Don't put force on the cooling fins or they will break. The recommended way to remove a flywheel is to use a puller. An alternative, is to tap on the crankshaft top, with a brass hammer or use a punch tip on an air hammer. The flywheel will need to be held up and supported or upward pressure applied with 2 large prybars. (A 2 person job.) Care is needed so the flywheel doesn't crack or bend. Also be careful to not mushroom over
the crankshaft top. Replace the key. Install the flywheel after cleaning the tapers and re-tighten the nut to 65 ft/lbs. There is also the possibility of a bent or twisted crankshaft depending on the severity of the impact but usually the key just shears.
Let me know how you make out.
Michael
