rebuild, not starting, ideas?

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tony172
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Hi, built up a 150 super motor, with a conversion crankshaft to use a p range flywheel, using a p range elec flywheel (2 woodruff slots) and a p range stator.
It was not running when bought. Everything has been replaced and rebuilt from scratch. Loads of compression, loads of spark, plug is wet/getting fuel, but not a peep. I have tried both slots in the flywheel and have tried numerous positions of the stator plate (including not only turning it on the slots but changing the slots round to different fixing bolts!) and have tried with or without the stator spacer that was recommended by sip. Always getting a spark (although the flywheel is ridiculously close to the pickup) but not even a hint of firing. any ideas?

There is no marking on the casing that i can see, or on the flywheel cowl.

I know the carb settings won't be right but it should still have some sign of life! I've even chucked fuel down the plug hole and nothing.

anyone experienced this or similar before? There must be loads who have converted an old points engine....

Thanks,
tony
mick1
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To check your timing (as that seems to be an issue) remove the spark plug and use an electric drill to spin the flywheel. If you've marked TDC on casing and flywheel, when strobing it should give you an idea where the firing point is.

My initial thoughts are an air leak (seal, carb, head, etc) but the timing is easy to establish first.
tony172
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good thinkin batman! i'll have a crack!
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lockman69
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Piston round the right way ?
goldeneye
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my money is on the flywheel, ive got a scoot in that wouldn't run with the twin keyway electronic flywheel fitted , swapped it to a standard old heavy flywheel and it fired up after a few kicks. it sparked like a guddun with the plug out. probably the keyways a mile out.
tony172
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Ok, so it did seem that the keyway was a mile out, but after cutting new slots and strobing with the drill method, we've got her set to 20btdc. good strong spark too. also checked the piston and its the right way round, arrow to the exhaust. still not a peep. :( atomised fuel is squirting into the venturi while turning over.
I can't see what the flipping problem is!
Yanker
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Is the crank chamber possibly now totally flooded with fuel as "atomised fuel is squirting etc." ? You tried the flooded/clear-out routine?
mick1
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any sign of petrol in the gearbox ? possible seal leak or casing crack.....
GLscoot
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CDI unit. Im going with electrical. Have you checked cut off switch on headset.
tony172
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will check the oil, and have left to clear/stand for 24hrs before trying to re start (as well as spending a few hours strobing it with the plug out). there is no kill switch involved yet the only wiring connected is the 3 from the stator to the cdi unit. I do have a cdi kicking around i could try though so i will be doing that too. Thanks for the ideas fellas! IT WILL F*CKING RUN!!
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