A theoretical question. Filter blockages and engine power.

[Pete]

Ok Barry,

so what you are saying is that if the gasolator was a mile across and half of it got closed off, then the flow through the remaining half mile wide opening would be reduced. Now that's plainly dumb, if the gasolator screen is orders of magnitude bigger than the pipework, then the resistance of the screen is not a factor.

If 50% blocking of a gasolator can cause an engine stop, then it is clearly under sized.

I

[Trevor Lyons]

... those plastic cheapo auto filters are a no-no ...

Assuming this refers to the clear plastic ones with a paper filter element, what is supposed to be wrong with these? Motor-cycles have used them safely for years! Is the "problem" that the paper element might break up? If so, does this happen? Or do these paper filters clog up too quickly?

I accept that if the engine is fuel-injected rather than carburetted (as indeed all aero-engines should be!) then there must be a final filter capable of trapping really tiny impurities of <40 microns. But would not a preliminary paper element filter earlier in the supply line be beneficial? After all, if it is "cheapo", then it is surely more likely to be regularly replaced.

[Julian Bone]

fuel should be clean
tanks should be clean
filters should be clean
just do the necessary maintenance
very fine filters pretty pointless except for injected engines
fine filters that cannot be checked just have to be regularly changed