Modern Vespa

I live in Japan.
Sorry for my poor English.
There is very little information about Modern Vespa in Japan.

I have recently acquired an ET2 (2000 carburetor) which is not working and I am repairing it.

I have replaced the broken CDI with a new one and confirmed the spark.
Carburetor has been cleaned.

However, the tank does not supply fuel.
I have ordered a new fuel cock but have lost track of the connections.

Could you please tell me the role of the two hoses from the fuel tank and the inner diameter size of each?

I think the top thick pipe is the vacuum valve and the bottom thin pipe is the fuel, am I correct?

Thank you in advance.

The top one is 6mm inside diameter and it goes to the fuel side of the carb. The bottom one is also 6mm, or 5mm if you have it, and it goes to the front of the carburetor, where the vacuum port is. Here is how to test the fuel valve, and the auto choke on the carburetor

Dear Motovista.

Thank you for the tube size information.
And the picture of the test method!

It is very helpful to know how to test the auto choke.

I had thought of the fuel cock positioning relationship in reverse.

I am now waiting for the new parts to arrive and will test them as soon as they arrive.

Thanks! ARIGATOU!

どういたしまして
一部のヤマハスクーターは、ベスパET2と同じ燃料バルブを使用しています。
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