Piston Ring 545154009

Disassemble blower, engine, and remove stuck ring. Reinstall new ring,reassemble all in reverse order.
The most difficult job was removing the stuck ring.

Remove air filter.
Remove plastic engine cover and disconnect spark plug wire.
Remove carburetor.
You can leave the fuel hoses connected, just swing carb to the side.
Remove exhaust header by removing two torx screws.
Remove two cylinder Allen head bolts. In my case one had backed all the way out.
Lift cylinder head straight up. At that time you can see the piston.
Replace the head gasket (small o-ring type).
Remove old piston ring and clean ring groove with rag and something like brake cleaner.
Carefully expand the new piston ring and begin fitting it into the groove. For my Poulan leaf blower there's a small pin in the ring groove. The split will need to fit onto one of these pins. You'll also note that the end of the piston ring is slightly rounded on the bottom. That rounded portion fits over the pin. To verify its on correctly, compress the ring and ensure it will compress to the size of the piston.
After the ring is correctly installed on the piston and head o-ring is in place, place some oil on the ring and bottom of the cylinder. This will aid in inserting the piston back into the cylinder head.
Hold the piston up as high as possible with two fingers, and begin pushing the cylinder down onto the piston. Using a slight side to side motion the cylinder should slide down over the piston. Don't force it. If it doesn't slide on with some moderate pressure stop and check to ensure you have the ring on properly.
Another option si to remove the piston and piston rod. This is easily done by remove a plastic cover with two torx screws on the outside of the engine. With that remove the piston rod will slide off of the engine shaft. This will allow you to flip the cylinder upside down and insert the piston. In this position, it's easier to compress the ring with your fingers or a plastic screw driver (don't scratch anything).
When it's on, put everything back together in reverse order of above.

1. Removed the plastic housing and the fuel tank.
2. Removed the carb assembly.
3. Removed the exhaust unit.
4. Removed the crankcase side cover.
5. Removed the ignition plug wire
6. Removed the cylinder unit.
7. Removed the piston assembly.
8. Removed the damaged piston ring.
9. Cleaned the piston ring groove and the piston unit.
10. Inspected and cleaned all components.
11. Assembled the complete blower in reverse order.
12. Put in fresh fuel and successfully tested the blower.

eReplacement has the inventory of replacement parts at a very reasonable price with fast delivery. I needed a piston ring for a Craftsman chainsaw no longer supported by Sears. eReplacement had the part (<$4). Within a week my chainsaw was back in action.

After a few years my chainsaw was difficult to start especially when hot. Disassembly was relatively easy using tools made for hex and star shaped screws. After removing the cylinder head (access the 2 hex screws through the holes with an Allen wrench) and slipping the connecting rod off the crank, I found the ring compressed by heavy carbon deposits. Heavy carbon deposits on the piston and head walls were removed using a Scotch-Brite pad. Soaking the piston/ring in Marvel Mystery oil released the ring from the piston groove. After installing the new ring (making certain the ring split was positioned to the intake side) and reassembly, the old chainsaw runs like new.

Sears 25cc blower had a clogged piston/ring. Burnt oily/varnishy deposits Ring broke on disassembly, after cleaning the piston, new ring installed easily. New head seal fit correctly. This machine was free, who knows how it was treated. Runs well now!

Removed the head and replaced the ring. Then, reassembled.

I purchased the blower at an auction. Did not know why it wouldn’t start so I took it apart and saw that the piston wring was burned and compressed inside the piston groove. That’s why it had no compression. So I replaced the ring and gaskets, put it back together and it ran great.

Take head off, put new ring in. clean ring grove out before putting the new ring in.

1. Watched several YouTube videos on fixing this problem and started by partially removing the blower case.
2. I replaced the carburetor and checked the spark (good) - still not starting
3. I removed the muffler to check for spark screen blockage, carbon buildup between engine and muffler, and to inspect the piston/ring. I tried starting it in this condition - still not starting
4. I finally decided that the piston ring might be stuck. I removed the cylinder and the crankcase cover, pulled the piston and rod off the crank shaft, and verified the ring was stuck in the grove with carbon.
5. I tried to free the ring with a utility knife cutting around the ring/grove but I broke the ring when trying to pry it out. Should have spent more time trying to free it.
6. I ordered a replacement ring and spare (in case I broke the first one installing it) and some case screws which missing from ereplacementparts.com.
7. After the parts arrived I sprayed the piston with lubricant and slid the new ring into place. I then sprayed the inside of the cylinder and rod's crank bearing with lubricant and reassembled the engine.
8. I reinstalled the blower's case, added fuel, and got it to start.
Success! This was my first time doing repair work on a small engine and ereplacementparts.com had what I needed and the order turn around time/price was good.

Remove plastic guard unbolt carburetor set aside remove Muffler unbolt head remove cylinder head clean piston replace ring put back together in reverse,it took more time to clean then repair