No spark

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mattyboyc
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Main scooter: Lambretta Li 150 series 3
Location: Aldershot, Hampshire
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Hi all,
Can someone put my mind at rest, I was out on the scooter last Thursday, came back parked her up. Yesterday I adjusted the gear cable as I was struggling to ge 4th, now after doing that I went to start her to test the gears and nothing, I have no spark to plug but have power to headset as if I kick her over with horn pressed it sounds but nothing to plug.I have tried a new plug, cap and HT lead but still nothing. Did I do something when adjusting gears or is it just coincidence that this fault has just appeared. Any help greatfully received. My knowledge is limited but hopefully I can middle through with some help!!
Thanks
Matt
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garry inglis
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check you havent pulled the green loom wire from the coil
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HxPaul
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garry inglis wrote: Tue May 22, 2018 1:38 pm check you havent pulled the green loom wire from the coil
Surely it would run,but not turn off.
mattyboyc
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Posts: 26
Joined: Tue Sep 12, 2017 2:02 pm
Main scooter: Lambretta Li 150 series 3
Location: Aldershot, Hampshire
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Thanks for your reply’s. I’ve checked all the wires as far as I can, I may well have to take the sleeving off and have a closer inspection but I can’t quite see how a wire could break purely from being parked and I can’t find any evidence of a crushed cable.All was good on my return from a ride on Thursday evening,I stopped it via the stop button put the cover on and that was it until yesterday then nothing. I have power up to the horn and headlight so can’t all have failed as if I push horn and kick it over the horn sounds, same goes for headlight.
fritz
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Have you checked cut out button has not got stuck in?
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coaster
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The fact that you have power to the horn is irrelevant as the ignition uses its own coil on the stator and is completely independent of the lighting coils. The ignition coil generates a spark all the time the flywheel is turning and the only way to stop the engine is to short circuit the ignition feed to earth. This is done via a green wire that goes into the main loom near the CDI unit. If you look at your CDI you will see there are 2 greens ant this is one of them, the other is the ignition feed from the stator. When you press you stop button or turn the ignition switch, you are shorting the green to earth. It is quite possible for an earth fault to develop in the green wire or the switch / button it is connected to and kill your ignition. Not saying that is your problem but its quick and easy to pull the loom green out of its connection on the CDI which IF there is a fault on it, this will remove it (you'll have to stall the engine to stop it).

If you have access to a multi-meter then there are some checks you can make on the LT coil and pickup.
mattyboyc
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Posts: 26
Joined: Tue Sep 12, 2017 2:02 pm
Main scooter: Lambretta Li 150 series 3
Location: Aldershot, Hampshire
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fritz wrote: Tue May 22, 2018 9:56 pm Have you checked cut out button has not got stuck in?
I have in so much as pushing it and making sure it returns but will do a continuity test on it in the morning.
mattyboyc
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Main scooter: Lambretta Li 150 series 3
Location: Aldershot, Hampshire
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coaster wrote: Tue May 22, 2018 10:13 pm The fact that you have power to the horn is irrelevant as the ignition uses its own coil on the stator and is completely independent of the lighting coils. The ignition coil generates a spark all the time the flywheel is turning and the only way to stop the engine is to short circuit the ignition feed to earth. This is done via a green wire that goes into the main loom near the CDI unit. If you look at your CDI you will see there are 2 greens ant this is one of them, the other is the ignition feed from the stator. When you press you stop button or turn the ignition switch, you are shorting the green to earth. It is quite possible for an earth fault to develop in the green wire or the switch / button it is connected to and kill your ignition. Not saying that is your problem but its quick and easy to pull the loom green out of its connection on the CDI which IF there is a fault on it, this will remove it (you'll have to stall the engine to stop it).

If you have access to a multi-meter then there are some checks you can make on the LT coil and pickup.
Thanks for your reply, I have followed this guide, done all the tests stated and still nothing, I will run through them again just to double check everything.

http://www.afrayspeed.co.uk/index.php?page=Per_nospark
mattyboyc
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Main scooter: Lambretta Li 150 series 3
Location: Aldershot, Hampshire
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Continuity test on cut out switch shows switch is ok so it’s not that. I do have a multi-meter so any help with checks to try and find the fault will be greatfully received.
Thanks,
Matt
bazza3004
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Mate went out on his Lammy Saturday before last and it ran perfect. Went to start it last Saturday to come on a ride out and no spark. I went round yesterday and swapped the stator (electronic) and it fired up first kick. These things can just pack in without warning and seemingly while parked up in garage lol
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