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cr250 no power, hard start
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Author:  fpd4 [ Tue Jul 19, 2011 2:21 am ]
Post subject:  cr250 no power, hard start

Okay, so I recently got a 1975 honda cr250 elsinore. It had sat for several years. The engine was seized and some mice had made it a home. I unseized the engine, cleaned out the mice houses and it ran. From what I read I had a lean bog, from about 1/4 to full throttle (it could idle okay and just putt around). It could run to about 1/2 throttle with the choke on. But then not idle well at all. I cleaned out the carb real good and now I believe I'm getting a rich bog, consisting of sputtering and no power. It is very hard to start and always has a wet spark plug when removed. The carb is real clean and I also installed an inline fuel filter so no debris would enter throught the old tank (although it looks clean). I am stumped, any help? My cousin (who is a motorcycle mechanic) suggested that maybe it needs to be held at full throttle for a bit to burn out excess oil, that he said can build up in two strokes. Sorry for the long post, and thanks in advance

Author:  fpd4 [ Thu Jul 21, 2011 1:15 am ]
Post subject:  Re: cr250 no power, hard start, low compression

Update:
I found out it has low compression. (About 80 psi). If it sits it will start right up and run good for about 5 minutes, it slowly loses power at higher rpms and eventually won't hit the powerband. After it dies it is impossible to start till it sits again. The plug comes out black wet. Any help on what to replace? Piston rings, some type of gasket? Thanks

Author:  ~JM~ [ Thu Jul 21, 2011 11:55 am ]
Post subject:  Re: cr250 no power, hard start

Poor a small amount of some thick motor oil (30wt) into the spark plug hole & try your compression test again. If your readings are now higher, than most likely the rings need to be replaced. The oil will help seal up the rings briefly while you perform the test.

Good luck
~JM~

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