I just tried starting my lawnmower (Lawnboy EasyMulch) after it had been sitting in my garage all winter. I pulled it out, cleaned it off (a lot of oil had spilled out), and gave it a basic maintenance (nothing fancy, just what I always do every spring):

  1. Change oil
  2. Add gas
  3. Change spark plug
  4. Change air filter
  5. Scrape off any grass that is caked on to the blade or around the chamber where the blade spins in

I went to give it a start and the cord will not pull. It won't even budge. When I flip it on its side I am able to wiggle the blade back and forth a little bit, but not able to spin it. Any ideas as to what is going on, or how to diagnose? Again, I scraped off a small amount of hardened grass clipping from underneath the mower, but there's nothing that is blocking the blade from spinning...

Thanks in advance!

2 Answers 2


Piston Seizure, possibly rusted piston rings from winter moisture.

The oil loss is worrisome, pointing to the first which means the piston skirt welded itself to the cylinder wall.

If the lawnmower was running fine before being put away, if it was left outside, moisture can get into the engine. Rusted piston rings sometimes taken care of by a liberal amount of WD-40 down the plughole and a week of sitting followed by working the blade back and forth till the piston moves.

Both conditions usually mean engine replacement as the cylinder is probably toast and ring rust can trap the rings in the ring groove causing excessive blowby and poor compression.


If you are not able to spin the cutter blade freely around then it sounds like either the main bearings or the piston has seized up. Either one looks like a major repair with engine overhaul.

There is also the other smaller possibility that something has blocked the flywheel. This could be some bent shroud piece or some debris (ie small stone or gravel) has lodged itself in the area where the flywheel has a narrow gap by the magneto coil. In this case you still are looking at some dis-assembly to take a look.

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