can anyone help with my vespa pk50 engine cut out problem?

[henro]

Hi all,
>
> I have a query regarding my enging that I am hoping someone will
be able to help me out with. This morning I was on the way to work
and riding on a long straight at 50 km/h without the throttle on
full and when I got to some traffic lights, just as I was starting
to slow down, the engine cut out.
>
> I waited a few seconds and then managed to get it going only to
ride another 2 minutes for it to cut out again. This then happened a
3rd time just before I got to work.
>
> This has happened once before when I was really going for it
downhill and I can understand that that time it may have cut out due
to overheating. This time, however, it is winter and v cold and I
checked the engine when I got to work and it wasn't that hot.
>
> Yesterday I filled the tank up but added the oil straight to the
tank and then added the petrol. This is the only thing I did
differently but cannot see how this could have affected anything.
>
> Any help much appreciated as my bike is currently stuck in the
underground carpark at work and I need to get home this evening! :)
>
> Thanks '
>
> Matt

[DivaDebs]

Hi there Henro,
Sounds like fuel starvation to me. Is the fuel filter blocked? Have you run the tank very low on fuel before? - this can cause debris to get pulled through the system & block things up. Try following the course of the fuel from the tank to the carburettor to eliminate this. When I get symptoms like this, I temporarily use pieces of clear tubing in place of the black fuel line to monitor the progress of the fuel.
OR, it could maybe be a loose or corroded earth connection.
Although I own a Harley, these principals are the same for any vehicle. Hope this helps.

[DivaDebs]

Hi there Matt,
Sounds like fuel starvation to me. Is the fuel filter blocked? Have you run the tank very low on fuel before? - this can cause debris to get pulled through the system & block things up. Try following the course of the fuel from the tank to the carburettor to eliminate this. When I get symptoms like this, I temporarily use pieces of clear tubing in place of the black fuel line to monitor the progress of the fuel.
OR, it could maybe be a loose or corroded earth connection.
Although I own a Harley, these principals are the same for any vehicle. Hope this helps. Simon.

[DivaDebs]

Did you get on the road again Matt?

[henro]

hi there,

Yes i did get it back on the road and indeed it proved to be a fuel starvation problem.

I had a problem with the fuel tap and was not aware of it meaning the engine was running of v low. Now I've sorted it and the tap is fully open there are no problems.

Just one other question though... when mixing fuel for my vespa is it always best to mix it in a petrol can before filling the tank rather than putting the oil straight into the tank and then the petrol on top?

thanks again

henro

[DivaDebs]

Hi Henro,
Really glad you got it sorted. I reckon it's best to pre-mix the fuel in a clean petrol can first if possible, then you can be sure it's properly mixed - which is really important with a two-stroke engine, as the oil in the fuel mixture provides the sole means of lubrication to the piston.
Best regards,
Simon.