My Hunter 35.5 had a little seawater leaking from the exhaust hose just aft of the muffler. I replaced the hose with a new one. I could not find the length required anywhere, but had a piece that was 84 long. It turned out to almost be the exact length I needed.

Let me describe the path my hose took from the factory. It goes aft from the muffler on the starboard side of the shaft bilge area through the bulkhead and continues aft along inboard side of the batteries. Then it bends up and forward where it goes through the deck above the batteries at the bottom of that starboard locker. The hose then loops up in a 180 degree bend and goes back down into the area on the outboard side of the batteries. It then makes a bend to attach to the hull fitting.

Now for the job. I removed hose clamps behind muffler and at hull fitting. Wow, that hull fitting is hard to reach. The hose came out fine from the muffler end, but was really hard to get off the hull fitting. I twisted the free end of the hose back and forth and finally got it to break loose.

Now the hard part, routing the new hose (thicker and stiffer than thet factory hose). The problem is the hose was too stiff to route through the hole going down into the battery area and make the bend to connect to the hull fitting. After numerous tries and a bunch of bruises on my chest, I gave up on ever getting it to attach to the hull fitting in that manner. What I did is to take the two screws out of the 1x2 that holds the deck covers over the battery on the forward outboard end that is just aft of the hole near the hull fitting. I used a block of wood to break loose the glue holding the 1x2 in place and broke it loose. I then cut through the wood decking to create an opening that would allow the hose to be connected to the hull fitting and then be pushed into the hole going down to the fitting. I then was able to route the hose the rest of the way, following the same path, back to the muffler. Whew!

Then I glued (woodworkers glue) piece I cut out onto the 1x2. I had cut out one of the screws holding the 1x2. I used the one screw in the cutout area and added a second screw and countersunk it next to the other screw in the cutout area. Then I added an additional screw in the 1x2 outboard of the cutout to hold the 1x2 in place while the glue dried and to add factory equivalent strength to the deck in that area. I had to push hard to get the hose into the original hole area to get the 1x2 and cutout deck piece back in place, but it worked out well and could be done again, with less work next time (in another 20 years or so....). I did not take any pictures, but could get one of the mods I made to the battery compartment decking.

Id recommend checking your hoses as a leak would also leak carbon monoxide into your living spaces. The factory hose was like a heavy vacuum cleaner hose where your could see the wire inside the hose. The new hose was much thicker and you could not see the wire in the hose. This hose runs over $10 per foot, but I had found mine at a marine garage sale in Seattle and bought it for a short piece I needed and happened to have the left overs that were the right lenght for this job. Good luck! Mike