Empty float bowl on Twin Solex Carbs

[toolsntat]

2.0 CU Aircooled
Any one had experience of float bowl siphoning (not completely empty)after a journey.

With air cover off you can see wifts of vapour coming out of body when warm.

Any thoughts?

Cheers Andy

[bigherb]

May just be due to the fuel level in the float chamber expanding from the rising heat from the engine, modern fuels seem to be more prone to it. I fitted 1.5mm instead of the 1mm float valve washers to lessen mine, but can also be caused by the float valves dribbling. Also make sure your fuel lines run below the top of the carb level to stop syphoning.

[toolsntat]

Ok,no problem with the fuel lines in this case.
With the expansion theory, what route would the fuel be taking to enter the manifolds?
The inlet valve was blocking when I blew through it.
Cheers Andy

[toolsntat]

Thinking about it,it must be more than expansion, as the level when cooled, is down as far as the bottom of the brass slow idle emulsion tube.
Had got to wondering if this tube was the culprit as I know it has a small hole at the top which is closed off when cold and open when warm.
Cheers Andy

[bigherb]

Liquids find there own levels if the float chamber rises the level in the jets rise.