Emergency fuel supply.
If your main fuel supply is badly contaminated and you are unable to clear it sufficiently to be able to continue to run the engine, there is an emergency approach that may work.
If you run a length of hose from the spare fuel container to the inlet end of the fuel filter, and run a second length of hose from the return end of the fuel system back to the spare fuel container, the engine will run quite happily as long as the fuel lasts.
If the spare fuel container is positioned above the fuel filter you may not even need to bleed the system.
For this to work you need to carry enough spare hose and suitable connectors in your spares kit.
If you run out of fuel in your spare container, it may be worth trying to filter fuel from the main tank through a pair of tights.
I had a student who had to run an engine for 20 hours, by filtering the fuel through tights in to a bucket, then used the above technique to deliver the fuel to the engine.
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