Peugeot 103 Won't Start

Mark De Bernardi /

Hey Everyone!

I'm having some trouble with my Peugeot 103. Was riding one day and the engine quit running. Now it won't start or even fire.

I have checked the spark and get a nice fat spark.

I have sprayed starting fluid into the intake box and still nothing.

I checked the compression and it had about 145 psi.

Seems like those three items should give me a running moped. But I get nothing.

I'm not very familiar with 2-stroke engines. What am I missing? Any ideas?


Re: Peugeot 103 Won't Start

Mark De Bernardi /

I just did some more diagnostics and it turns out that the spark plug isn't firing when it's installed in the head. When it's out and grounded against the head it sparks nice and fat. Then it's installed -- nothing.

Is it possible that there is too much compression to let the spark plug fire?

If so, what could make this abrupt and unexpected problem occur?

Re: Peugeot 103 Won't Start

There are a couple of things that might be going on here.. I've seen many marginal ignitions that would fire a plug in free air, but when installed in the motor, the swirling compressed mixture "blows out" the spark. But in these cases, the spark never looked quite like it should.

Have you tried a new plug? There are certain types of fouing that only give trouble when they are in the presence of compressed mixture. Also, never hurts to clean the points with some brake cleaner, and check the gap.

Re: Peugeot 103 Won't Start

i would change out the spark plug--they biuld up some black grud

after a while--and even thou you clean them--they still don"t fire proper...

check your timming--on my 102sp--if the flywheel nut is not good and tight - the timming gets off--even thou you have a good spark--it is not going to run with bad timming.....................

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