Karl & everyone
A few of us were talking about this at the PFA Rally couple of weeks
ago, someone pointed out that there is another possible source of
smells. The tank breather. When the aircraft climbs, air in the tank and
breather system has to expand.
When refueling some fuel gets pushed into the breather pipe, (I've seen
it many times.) After take off any air trapped in the tank will expand
as the aircraft climbs, the only way it can do that is up the tank
breather so fuel will get pushed out the breather, hence the blue stains
on the fuselage. The same thing happens if the aircraft is refueled
cold, then the sun comes out and we warm up.
Paul McA and I put the breather syphon break into the top of the XS
filler trunk which should prevent any fuel being expelled.
Graham
Karl Heindl wrote:
> Guys,
> Before blaming the carb heater for the fuel smell, why not be 100 %
> sure before adding mods. Just disable the coolant flow by putting a
> clamp on one hose for one or two test flights, and get the engine nice
> and hot.
> I have fuel smells, too. But in my case one source is the old hoses,
> some of which I will change at the next annual.
> Karl
|