But I was replacing one of the hoses just due to their apparent age, and the way the clamps dug into them. (I didn't like the wear at the clamps... where the hose material is forced through the clamp. I am using a different style of clamp that does not dig the threads into the hose) But the hose was not clogged at all.

The clogging seems to be confined to the mixing elbow and the waterlift muffler input port.

The exhaust riser is pretty clean, as were the pipes that connected the riser to the mixing elbow.

I'll pull the hose on the muffler output port this weekend and take a good look. I may remove the muffler and take a better look at it. (in it)