Modern Vespa

I am getting lots and lots of fuel pouring from my carb bowl overflow pipe, after the engine has run for 10mins or so.

I stripped the carb and looked the float, and it seems all right. I didn't take it off the carb body as the pin didn't want to move. (Is this how you remove the float?). I checked the needle valve, by blowing into the fuel inlet, and it closes ok.

I put it all back together, and I got the same problem.

It only happens when it is hot. Is it just a new float and valve? What are the phyiscs involved that means it happens hot?

Its my wife's bike. It is broken down by the side of the road now in a dodgy Parisien suburb. I had to leave it and get a metro to get my wee boy from school. I do not think even my best attempt at cooking a nice dinner will suffice.

We brought the bike home, spraying fuel onto the road as we went, definately from the overflow pipe. I bought pizza. Everything is good.

I looked up the price of a float and it is £62:76 excluding shipping. That stopped me in my tracks.

So I put the carb, minus the float bowl into a bucket of hot water, and the float has no leak, and blow as hard as I can, I can't get air to pass the needle valve when the float is in the up position.

What can cause the overflow?

I'm not too familiar with the ET4, but from what I know there's a fuel pump or valve that can cause this, if the diaphragm inside goes bad. This happened to a friend of mine who rode an ET4 on the Cannonball in 2006... gas was everywhere. Can any other ET4 owners provide some more specific info?

Gots to be the float or the valve, could be wrong though.

Won't be the fuel tap as that is only a problem when you shut the bike off and it fails to turn off.

Bit cheaper here...65US plus shipping. Still not cheap.

http://www.athensscooterco.com/eshopprod_cat_4797-48549-48411_product_598151.T20_CARB.htm

Sounds like its sticky....

R

8)

I think i remember you posting that you had a pre leader engine? if so make sure your order the right part!!! wait till some of the euro folks are online and bump this topic then as the pre leader never made it to the usa.

OK. I was looking for something clever and complicated, which wasn't there.

It was a bit of plastic in the needle valve. Blowing out the valve only moved the plastic enough to make the valve work but not remove the plastic completely, so randomly during driving, which i mistook for something happening when the engine was hot, the plastic reblocked the valve.

All the answers are in the forums which means I just saved 62 quid. I'm having a good day already.

What kind of plastic? Where do you think it came from?

No idea as to where the plastic came from. I showed it proudly to my wife, and she dropped it, possibly into her cereal. We didn't look to hard.

But I couldn't find any more traces in the fuel system, so fingers crossed it is a one off.