Modern Vespa

Hello all,

With the nice weather in GA, I decided to take the LX150 for a nice ride.

After about 3 miles, it started to surge, bogg down and then stalled. I waited maybe 30 seconds, started right up and so I rode it home.

The scoot only has 400 miles on it, bought it used, dont know the history.

The only thing I have done, is changed out the fuel pump with a manual petcock.

Thoughts what may be the issue. Not comfortable riding it again.

To be clear, did you eliminate the fuel pump before or after the stalling began? Why?

Maybe reverse this change ...

The fuel pump was not working when I purchased it. I read about the issues with the electric pump, so I purchased the manual one.

It starts and runs/idles fine.

I have not driven more that a mile until last night.

I ain't no carb expert but wouldn't the jetting be setup for the pressure of the pump?

I suspect the correct solution is to just use a working pump and no petcock

As far as I know, a 2008 LX150 is fuel injected. Fuel injection needs the constant pressure of a fuel pump to run correctly. I'd get a new pump before trying any more troubleshooting.

The 2009 is injected whereas the 2008 is carby with a pump.

plus or minus a year in different countries etc

Correct, it is carbureted.

That year, had either a fuel pump or vacuum petcock.

Since that year had either one, I believe the jetting is the same.

Should the fuel line have some type of insulation around it? I was thinking initially vapor lock, but it started just after 30 seconds of stalling.

Thanks for the correction. I still think I'd start with a new fuel pump. It's there for some reason.

also, being an old carb ... have you cleaned the jets?

I took off the fuel bowl, inspected jets, super clean.

Idles and runs fine, even the electric choke is working fine as well.

Well as both JKJ-FZ6 and I have suggested, fix/replace the pump is probably the best place to start.

Thank you.

I was also thinking, could this be an evap issue? I see where many have removed it.

check part numbers of carb and jets etc to confirm

I assume you did carefully inspect *all* hoses for cracks ...

All hoses look good.

I replaced the vacuum lines from the intake manifold to the carburetor. Replaced the fuel line as well.

I'm no carb expert either, but I would look for air leaks in the intake manifold.

Tried spraying carb cleaner around the manifold to test for leaks?