In case this is useful to any Kitfox pilots out there:
Flying my recently purchased 18 year-old Kitfox III I experierienced sudden loss of RPMs (a thousand at a time) with the 582 engine actually spluttering as if it would stop; fortunately it did not and I was able to land safely quite a while later. I dismantled the carburetors and found both jet assemblies full of fibres that were clearly partially obstructing fuel-flow. I had a couple of eventless flights after that but on another flight just recently it happened again and once more the jets were found to be full of fibres! I have now put in an additional BMW fuel-filter in the fuel circuit above the gascolator (the paper-like membrane type) which should finally take care of these horrible fibre-shedding old tanks. I have had a long flight after this latest repair and the engine ran as smooth as silk, I hope the problem has now been definitively laid to rest. Have any of you faced similar problems?
All the best,
Kiriako