engine fault .. help needed

i have a engine, make unknown. it a single cylinder petrol oil mix,
its not very old, couple of years, when its started from cold or hot, it runs fine for about 5 to 10 mins, then
it runs as though there is a petrol blockage in the carb and i have to adjust the choke to keep it running, until i have the choke most of the way on, then after a few minutes it will splutter more and cut out,
the carb is clean, petrol flow is great.
spark is fine.
i have thought of mixture, and is it possible to be a loose head? thus allowing the gasket to blow a bit as it wars up?
these items seem to suffer from this problem after the first year or so. .. its on a lawnmower and i have read some reviews on them and lots of people have had the same problem,, / / / /
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Could simply be a whiskering plug. As a first step I suggest trying a new one.
hth
--
Roland Craven
Nr. Exeter, Devon, UK
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Or is it a diaphragm carb?
Roland Craven Nr. Exeter, Devon, UK snipped-for-privacy@petternut.co.uk www.petternut.co.uk
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It could also be enthusiastic over oiling of the mixture, the excess oil gathering in the crankcase and making the fuel in the combustion chamber progressively oily.
Are you sure you are using the right mixture?
What engine make is it?
--

Regards,



Kim Siddorn
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"kimsiddorn" wrote in message
It could also be enthusiastic over oiling of the mixture, the excess oil gathering in the crankcase and making the fuel in the combustion chamber progressively oily.
Are you sure you are using the right mixture?
What engine make is it?
--
no idea on the make m8, it was bought from b&q, its one of their own brand
names,
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Chinese then. I have a Chinese genny and it very cheerfully runs all day on 50-1. Without seeing the mixing bottle etc, I can have no idea I'm afraid.
I'm with Roland - buy it a new plug, preferably an NGK.
--

Regards,



Kim Siddorn
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Ryobi two-stroke? Is the cylinder barrel still bolted firmly to the crankcase? Any oil blowing out through the gap? Strip, clean, re-assemble with screwlock on the bolts. You will need an awkward size of Torx though (#27?) which isn't in most of the cheaper sets.
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ok folks, i got mixed up on this, thinking of other things i have.
the mower is strait petrol and not 2 stroke, its a 4 stroke engine, sorry about that, i just forgot what it was, i have never put 2-stroke oil in it,
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Dirt in the carb? I had this on a mower once. Fortunately it was still under guaranttee so the dealer fixed it. I did trace where the blockage was but it was in a sealed area of the carb. A new carb was only 35 though which surprised me. It was a B&S btw.
John
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On Fri, 10 Feb 2012 10:16:09 -0800, John wrote:

Blocked tank breather, maybe...
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Try this, it was just given to me on another forum, made me laugh http://www.nulon.com.au/products/Aerosols/Start_Ya_Bastard_Instant_Engine_Starter/#.T1SvcN8Zmw4

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