i took a little photo here to assist. i appreciate comments from actual tradesmen. what we have here is a vacuum petrol valve such as one would find on bottom of scooter tank. what i'm

looking for is a little glue to hold the fine mesh plastic filter in place on the aluminum casting( while submerged in gasohol . )while unboxing, i discovered the flimsy plastic tubes easily disconnect( pop out) and this is not how i want to install these

 

It doesn't look like the valve has a reserve on it.  If correct can you skip the siphon tube and install a simple but effective filter just downstream of the valve?  If your tank is older I think it would be a good idea to install the filter regardless.

 

Other options might be to heat the end of the tube to soften it and make it a bit wider to ensure a snugger fit.

 

As far as adhesives go you would need something that bonds to plastic well and is resistant to gasoline/petrol plus alcohols.

This could do it - https://multimedia.3m.com/mws/media/79749O/3m-scotch-weld-structural-plastic-adhesive-dp-8005.pdf

If you knew the type of plastic the tube is made from there might be other adhesive and epoxy options.

You can buy a tube of gasket sealer in motorcycle accessory shops. 

Buy a new tube as well. 

If you want inline filters,  Honda ones are 35 baht which I use. 

 

 

Surely when installed no one is pulling on the filter/tube to dislodge it?

yes, i think there may be an epoxy that's resistant to petrol. it quite easily detaches( as in a few hard jolts on road might do it. )

 

engine vacuum works valve ( closed when engine not cranking running) and if diapragm bad, it can starve motor of fuel. 

 

i've got inline filters. maybe removing it entirely easiest option????

Used this stuff for years.

Works well