ORIGINAL: maxtenet
... but what happened was a real mess in the fuel tank after a few flights...
Max
Max,
I read (SMALLnet, I think) about someone installing a catch box for the sludge. Install it between the muffler and the tank. Empty it after every flying session (or sooner if necessary).
I don't use muffler pressure so I have never tried it.
Hope this helps.
George