Peugeot 103 weak spark

We to the moped world but not afraid to get stuck in with a little guidance.

I have a 1979 Peugeot 103 LVS U2 that got to me as a non runner, the previous owner told me he could not get a spark. After reading a few blogs and internet searches I went to work but need more help.

Flywheel looks to be timed, mark is about 3/4” past HT cable at TDC

Points start to open when mark is at HT cable

I grounded the single black wire from the stator and spun the engine with an electric drill using the flywheel nut.

No spark from the spark plug, I removed the spark plug boot and bared the end of the HT lead and managed to get a very weak spark on the cylinder head.

My assumptions are the wiring is ok but one of the ignition components has broken down. Where do I start and how do I test them.

(I have not taken the flywheel off as I don’t have a puller but will get one if needed)

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Re: Peugeot 103 weak spark

its a weak design, look up on myrons page on pug 103 ignaition troubles.

Re: Peugeot 103 weak spark

There is a tutorial in the wiki on how to rewind these, it's really easy and it works quite well, I've done several.

Re: Peugeot 103 weak spark

Yeah rewind or if you wanna fix it for good the le partie: https://www.treatland.tv/peugeot-CDI-p/peugeot-cdi-after-partie.htm . Just be sure to replace the hardware in the stator with these: https://www.treatland.tv/peugeot-CDI-ignition-after-partie-ALLEN-bolt-set-p/peugeot-partie-allen-bolts.htm and red loctite em, buy this flywheel nut: https://www.treatland.tv/10mm-axle-nut-p/10mm-axle-nut-peugeot.htm and this puller: https://www.treatland.tv/19mm-x-1mm-flywheel-magneto-puller-p/19mm-flywheel-puller.htm . You can also lap the flywheel to the crank for a tighter fit, and put some loctite in the taper so that your timing don't slip as easy.

Re: Peugeot 103 weak spark

the only bummer thing with th le patiebis that you have to redo your brake light circuit from NO to NC or visa versa.

Re: Peugeot 103 weak spark

Downhill Harvey (OFMC) /

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