I've finally traced what I first believed to be a carb problem to a clogged exhaust system. The coach has sat for 5-6 years with only occasional starting and moving around the storage yard. It's still a little surprising as the entire exhaust system appears to be in decent shape externally but I have virtually no flow out the tailpipe. I confirmed there's no heat riser issue, it appears to be removed with the shaft holes plugged if there was even one there in the first place.

I'm puzzled as to exactly what is clogged...mufflers, exhaust pipe or tail pipe? I can't visualize how any of those would actually close up. It might help before I start tearing into it to know what's the likely culprit.

I've finally traced what I first believed to be a carb problem to a clogged exhaust system. The coach has sat for 5-6 years with only occasional starting and moving around the storage yard. It's still a little surprising as the entire exhaust system appears to be in decent shape externally but I have virtually no flow out the tailpipe. I confirmed there's no heat riser issue, it appears to be removed with the shaft holes plugged if there was even one there in the first place.

I'm puzzled as to exactly what is clogged...mufflers, exhaust pipe or tail pipe? I can't visualize how any of those would actually close up. It might help before I start tearing into it to know what's the likely culprit.

Sir: I was told at muffler shop that the factory Y pipe is spiral rolled when made and can unwind in the Y and restrict flow. Probably need a coathanger or a camera on a stick to check it tho. Maybe use a laser thermometer and try to locate the hot spot.

Mud Daubers.

I've finally traced what I first believed to be a carb problem to a clogged exhaust system. The coach has sat for 5-6 years with only occasional starting and moving around the storage yard. It's still a little surprising as the entire exhaust system appears to be in decent shape externally but I have virtually no flow out the tailpipe. I confirmed there's no heat riser issue, it appears to be removed with the shaft holes plugged if there was even one there in the first place.

I'm puzzled as to exactly what is clogged...mufflers, exhaust pipe or tail pipe? I can't visualize how any of those would actually close up. It might help before I start tearing into it to know what's the likely culprit.

I've got both off and now searching for replacements. Considering the two Walker models, the cheaper 18425 Sound FX model (probably louder) and the 4 times more expensive 22380 in stainless. The cheaper one is noted as 'perforated tube' internal construction and the other a more nebulous 'turbo style'.

And now that they're both out, I see what I presume is an aluminum sheet protecting the underside of the coach is bulging down and all crinkled. It doesn't push back up into place easily, it feels like there's something like insulation or padding between it and the floor. Is this condition common? Should I worry about correcting it?

Perhaps one of these links will permit you to see it.

"https://www.flickr.com/photos/59523128@N04/14559744855"
"https://farm3.staticflickr.com/2912/14559744855_bcf91c0cc6_s.jpg"

I never did read what was clogging the exhaust--was it indeed the mufflers? As far as the insulation goes, that is pretty typical. I left mine as is but depending how far it has dropped, I have seen others pull it up and support it with a couple of wire/cables stretched beneath the insulation. I can't say for sure but if you run some screws into the plywood above, those screws could get pretty hot.

If you have a strong shop vacuum with a 2 inch hose, put it on the exhaust pipe before you install the mufflers and see if the flow changes. There should not be any restriction for the vacuum.