Peugeot 103 Won't Start but has Spark

Hey,

I've been fixing up a 1978 Peugeot LVS U3 for the past few weeks.

It has a spark.

I cleaned the carb and everything looks good, but it won't start.

I think it may be because I have no "engine decompression" lever.

My bike didn't come with one but in the manual they mention pulling it to start the bike up.

Does anyone even know what engine decompression is/does? Do you think this is the reason the bike won't start? Do you know where on the carb/engine I should even hook up the switch?

Thanks for your help.

Dave

Peugeot 103 Won't Start but has Spark

Re: Peugeot 103 Won't Start but has Spark

Steve Murphy /

The decompression valve should be located in/on the cylinder jug or head (I'm not familiar with Peugots). It is a valve who's purpose in life is to reduce compression in the combustion chamber to make the bike easier to pedal-start.

Some bikes (Sachs) have the decompression valve connected to the clutch cable, so that when you pull the clutch in to start the bike, the valve opens.

If the valve is in the head and not connected to the cable, it won't cause any problems. If it's missing, you'll have a big hole in the combustion chamber, so the bike would have very, very low compression; enough not to start.

Re: Peugeot 103 Won't Start but has Spark

Don Pflueger /

spray somecarb cleaner in the carb throat. try to start the bike. if it fires, you have a fuel problem. if it does not fire, you have a compression or ignition problem. pull the plug and test for spark. if you havespark, then test compression. less than 120 lbs means it wont run. if it does, it will run very poorly.

Re: Peugeot 103 Won't Start but has Spark

Glen Stewart /

try adjusting the points i had a 1980 103 that didnt run and when it ran it ran like crap i adjusted the points and it ran fine i loved it.

-Glen

Re: Peugeot 103 Won't Start but has Spark

It will have a choke lever that you will need to use..My experience with a similar model is they are very cold blooded and need heavy choking to get them running. The decomp lever should not be needed to start, only as an emergency way of stopping!

Re: Peugeot 103 Won't Start but has Spark

Thanks to everyone for their suggestions.

Good news--I sprayed starting fluid into the carb and the bike ran for a brief period of time.

I guess it's some sort of fuel problem, because it won't start without starting fluid.

I broke down the carb before any of this and i cleaned it thoroughly, but I guess it's still not clean?

Thanks,

Dave

Re: Peugeot 103 Won't Start but has Spark

replace the gas line that is going from the gas tank to the carb

also check that the petcock (gas switch) is pointed in the "on" position

nick

Re: Peugeot 103 Won't Start but has Spark

Don Pflueger /

use wire in all the holes you can find. make sure the intake is tight.

Re: Peugeot 103 Won't Start but has Spark

Test fuel flow from the tank to the carb--your petcock may be clogged, or off. If you get fuel to the carb, you know the problem is either in your carb somewhere, or your fuel is bad (not likely)

Re: Peugeot 103 Won't Start but has Spark

Thanks again for your suggestions.

The fuel flow to the carb was good.

I'm going to work on the carb again...I think that's where the problem is.

Thanks,

David

Peugeot 103 Won't Start but has Spark

I installed a brand new factory carb from moped warehouse last night.

Now the engine will start with one kick.

However, it only idles roughly for about 10 seconds and then dies.

When I give it some gas it runs faster for a bit, but the wheel doesn't turn and then it dies.

The fuel flow is good. The spark is good. The headlight comes on halfway and flickers when its running.

Any suggestions???

Thanks,

David

Re: Peugeot 103 Won't Start but has Spark

im having the exact same problem lol

Re: Peugeot 103 Won't Start but has Spark

Did you adjust the idle mixture and the idle speed screws? If not properly adjusted yr ped won't idle correctly.

http://www.mopedarmy.com/wiki/Adjusting_the_Idle_Mixture_Screw

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