I've had 2 Robbins heat muffs on my -6 since day one (2000). I had trouble getting them to clamp the pipe tightly until I oversized the tie rod holes slightly. That allows the end cap halves to move past each other a little more and clamp the pipe. 1800 hours and no wear on the pipe.
RV-6 N207AM w/G3X, 1,800 hours +
South St. Paul, MN (KSGS)
A&P, EAA Tech Counselor
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