So in order to reduce the possibilty of a fire you've introduced a leak and you're going to fit a fire extinguisher. Not aimed at anyone in particular, but.. I don't "get" any of this! Never had a cut-off, never had an engine bay extinguisher, never had a sump full of fuel or a fire. What is the problem with just doing the simple basic maintenance to prevent what should be extremely rare occurances??
Remember when my sump filled up with fuel. !. My reason for fitting a fuel tap has little to do with fire.
By plastic handle I was more referring to being unable to turn it off if it had softened/melted. Not that the valve would melt. If you install a valve, try to fix it down and use a less violent curve in the fuel hose. It will tend to crack faster and vibration and fiddling with it in mid air wont help. You have put it in the pressurised section of the fuel feed. Convenient to get at but otherwise in the wrong place installed in a way that ups the risk of fire. Fit a solenoid valve securely outside the engine bay. Fix the carburettor - that leaking needle valve will eventually stop your bus by flooding the engine at idle or low engine load. Then you dont have to keep faffing . One day you will forget.
Hiya, don't forget i had to take off an electric solenoid valve as it appeared to be causing a 'vac lock' issue, but maybe the old fuel pump was a bit under par, new Pierburg on now. I would prefer an electric cut off solenoid underneath as long as doesn't create problems. I've rebuilt the carb twice including renewing the float valves and set/ checked the float level to the Bentley manual. Would the manual tap be better fitted between the pump/ carb?. Thanks for your input