# Craftsman 25cc Blower



## ribertgropius (May 22, 2007)

I have a 2 year old blower with not-so-many hours on it that has poor compression. Thinking I would find a scored piston/cylinder, I dissassembled it only to find that the cylinder and piston 'look' great, with no scoring, and I am at a loss as to why it would not have good compression.

Is it possible that the ring has gone bad without the piston/cylinder being scored? This was a refurbished unit; the cylinder has felt-pen markings on the outside making me think it was swapped out when refurbished. There are NO vertical score markings on the cylinder or piston, and everything feels smooth. 

The only thing I noticed is that the piston seems to slip into the cylinder very easily, making me suspicious of the ring. Does it make sense to just replace that part? Or should I just replace the piston and ring together? I am by no means an expert on engines, just curious about why things work (or don't work) and am puzzled by the lack of noticeable wear.

I noticed on another posting on this forum that Poulan makes this engine, and that the parts are available from Poulan at a reduced price from Craftsman. It is not an expensive unit; replacing the cylinder and piston together would total above $50, so probably not worth it. However the ring is cheap enough (if I can figure out how to get the old one off and the new one on without breaking it), and even the piston / ring assembly isn't too bad.

Thanks for the advice.

Robert


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## oscaryu1 (Mar 25, 2007)

yes the rings could have gone bad.... hows the head gasket? are the valves fully closed like they're supposed to be?


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## geogrubb (Jul 28, 2006)

Spray some carb cleaner or WD-40 on the rings then push on them with a small screw driver to see if they flex, it could be they are just stuck with carbon. Have a good one. Geo


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## ribertgropius (May 22, 2007)

Tried to loosen it last night; it was absolutely PACKED with carbon, and snapped as I started to get one side loose. So....I finished removing the old ring, cleaned out all the carbon, and ordered a new ring today. Is there any trick to getting the new ring on? Am I correct in thinking I can just slip one side down over the cylinder into the slot and gently push the remainder over the cylinder until it seats?

Thanks.


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## geogrubb (Jul 28, 2006)

I don't knowthe proper way without a ring expander, however, I don't think you can expand it as far as you are suggesting. I have expanded them just enough to get then over the piston then work them down like closing the lid on a paint can, tapping it down a little at a time all the way around until it set. Have a good one. Geo


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## ut1205 (Apr 14, 2007)

*Same Problem!*

I'm having the same problem with my Craftsman blower. Is there an "Online Repair Manual" giving proper torq specs for putting everything back together.
(Conn rod, head, ect)


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## ribertgropius (May 22, 2007)

I am told that torque settings on a little 2-cycle engine are not such a critical thing as larger engines. I think part of why this is true is that you are dealing with small fasteners in threaded aluminum: accordingly, they use o-ring type gaskets and locktite. How much torque can you put on a little allen-head or T-25 bolt anyways? 

I am sure there are some general guidelines for torque but I could not find them on the sears site. You might try looking on Poulans parts site to see if they have anything in the spec section. The similar poulan unit model number is listed in this forum on a posting by Hankster.


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## blackwell_316 (Jun 27, 2006)

the impeller nut, cyl bolts, and muffler are a 100inch lbs


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## ribertgropius (May 22, 2007)

Just wanted to thank everyone for their advice. Got it reassembled last night and it started right up. I was able to put the ring on just using my fingers to expand it. Hopefully, the ring will not carbon up again in the near future, but if it does, I now know how to fix it! Total cost: $8.50. Lessons learned: priceless!!!! (lol)


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