Exhaust Pipe Liner?
In the muffler replacement procedure, I have found within the
Exhaust Pipe Tube (vertical tailpipe) a liner material akin to rock-wool or fiberglass mat, which was not very difficult to slip out, the tube being frozen in place .. the Hood off the tractor. I do not see a separate part number for this material, so I'm wondering is this is some previous owner's DIY installation? This also begs the question, what is supposed to seal the muffler outlet, to the bottom of the exhaust tube, which is about 2-1/4" larger in diameter than the muffler outlet tube?
Komatsu has done a superlative job in isolating normal engine vibration from the tractor, so obviously there has to be some non-rigid connectivity between the muffler and the hood, so what is supposed to be used to fill this inch wide void around the muffler outlet?
On a side note, I was doing some very heroic muffler patching of little holes, and then reached up and felt that there was ZERO muffler exhaust tube .. just a big hole. I figured just 30 years of corrosion from the open exhaust tube pipe allowing rain to simply run down inside. So with that I got a 2-1/2" Rain Cap to install, but with the open void I'd still have the Smoky Engine Syndrome noticeable briefly during startup, and the new cap would not be getting the benefit of the full exhaust flow.
I invite your comments, experience, and solutions to this rather unusual engine exhaust design, and Happy Holidays .. Safe Journey!
Drawing including 6144-11-5760
http://komatsupartsbook.com/#?k=!0!2!1116!678!1!8