Maule Lycoming IO540, 260 mufflers

[Paul Amstutz]

Just finished the annual on 2007 M7260, 502hTT. No known problems. Plane runs very smoothly. 6 cyl JPI engine monitor. I run LOP in cruise. About 10GPH at 110-115 mph indicated at 8-12 K here in Utah, then ROP for back country operations down around Escalante. Steve Davidson, my AP/CFI suggested changing out the mufflers at 500hr from lengthy experience. They looked good from the outside. One muffler, original, had the flame arrester tube broken off. The other had completely disintegrated the flame arrester.
Steve says that Jeremy first alerted him to this issue, and that if the flame arrester tube is broken and redirecting the exhaust to one side, the result is a burned through muffler/cowl, or worse
This is just a FYI. My suggestion is listen to those with experience.
I am going to contact Atlee-Dodge, to see if they can use my old mufflers to make a new set/fixture for the 260. And replace it after another 300hr.

[maules.com]

The flame tubes are replacable provided the muffler is in good shape. Grind off the tack welds inside the exhaust exit, buy new perforated tube from mauleairinc, hammer on until it is small enough to slide in, then tack weld in three spots.
Knisley of CA or Dawley will rebuild old cracked mufflers using a part of the old one. Allee Dodge has a better muffler, heavier duty and heavier with enhanced heat transfer and a few more dollars.
Mount the mufflers with plenty of play at tailpipe attach, do NOT clamp down the U clamp and distort the tailpipe.
Do not over tighten the riser to header attach bolts as the cylinders move at different rates.

[aero101]

I've got like new set of original header / muffler assy's for the 235 / 260 available here in TUS, make offer if interested... Can ship...