The O-Ring sometimes swell a tiny bit, so after you took it of (for greasing it), you will have a hard time to put it back. The chance of cutting the O-Ring during the re-assembly, is high. Had is once, since then, I spend the money and replace the O-Ring, if I open the filter.
RV-7A, TMX-IO-320, FM-150, Sensenich FP
Flying since 28. April 2016