Fuel in u bend

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davefish
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Hi need help with a gp 190 it was running well then it just started with a drop in power when I pulled the throttle back then it stopped running altogether I checked the carb all ok then checked the spark that to was good so I started to drop the engine when I tuck the exhaust off it had fuel in the u bend
Dose anyone out there now why


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Morgan
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Obviously the fuel is what went through your carb and didn't ignite......but why didn't it ignite ?? I'd suspect lack of compression (if you've a healthy spark). lack of compression could be a holed piston, stuck (or missing) rings or bottom end seals blown. head and cylinder off then take it from there......enjoy !!
blue
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Sounds like it''s flooding, check the condition of your float and float valve.
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davefish
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Float is fine i striped the carb down cleaned all the jets and checked the float I also striped the head and found a lose nut next to the spark plug the thread was shredded. All put back together good compression but still will not start


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mick1
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The stripped nut would suggest your cylinder head was not bolted down sufficiently, thus losing compression and causing engine failure. I'm wondering now if you've warped your cylinder head ? again causing lack of compression. Is there a "squeaking" sound when kicking it over ?

There's been a similar post about running issues and the problem was a leaking mag flange, this was found by doing a pressure test. There's a nice little post on the LCGB site about how to rig a simple pressure test....might be worth a read.
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davefish
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Thanks mick1 no squeaking sound but I think a pressure test is the next thing will keep informed thanks


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davefish
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did a pressure test all looked fine next stripped the stator and found that the woodruff key had snapped plus the cable clip had gone
replaced clip and woodruff key and it started first kick but its back to the first problem no power when I try to pull away can any one shed
some light on the problem thanks dave
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davefish
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Joined: Sun May 27, 2012 12:20 pm
Main scooter: lambretta gp
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Replaced the stator with bgm one still on joy so I had a good look at the fly wheel the two pick up points had bent from the lose clip I assume so alls good now looking forward to the weekend so I can take it for a run


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