I have been replacing a few hoses on my system and although i am not an expert at it, i have found an easy way to manage the stiff hoses in the confined space.
others may have other ideas, but i doubt its any easier...
the muratic acid idea may not be the best, as you are going to be working in it and any accidental drips, splashes or spills, will be an acid spill... an acid spill is not a friendly spill. you can remove effluent smell with the enzyme, but acid can eat holes in fabric, rot wood, eat thru nitrile or latex gloves, and skin, and soften fingernails to the point to where you cant finish the job....
muratic acid has its uses, but im not sure this is one of them when you have to work in it.
any effluent that is lost out of the system into the boat can be washed away and pumped out later... followed by an enzyme that is left to work as it will, and then dry out or washed away later... it will kill any smell that is left behind.
dont be afraid of using a garden hose or getting water in the bilge... it will all work out and is an easy clean up AFTER the hoses are replaced.
from my experience in this cooler weather, heating the compartment where the hoses are for a couple of hours before beginning work is mandatory. this is not to keep your hands warm, but to help soften the old brittle hoses.
cut the old hoses off using a hook bill knife.... try not to cut too deep or into the fitting, and then use a screwdriver to pry the cut apart so you can remove the hose. measure and cut the new hose to the same length. after a couple of removals, you will get the feel for it...
for installing, I used a large pan of warm water that i kept heating, and used it to slightly warm the hose after I cut it to length.... let it soak for 5 minutes.
then... i used lanocoat and give the inside of the hose a very thin wipe for lubrication, and the fitting also.... as thin as possible and still feel the lubrication
when installing you must work quick as the fitting will be cooler than the softened hose and it will harden the hose quickly on contact...
when working with an elbow, install the cut lengths on the elbow first, THEN, install the long leg of hose first, then the short leg... hurry and get it all seated into place before it cools.
normally, if you try to install the short leg first, you wont have enough movement to allow the long leg to clear its fitting properly for have a good lead to slip onto it....
make sure you purchase a couple of extra feet, as you will need it... cutting a section off because it set up too quickly is normal, until you get the rhythm of how it all goes....
getting past the idea of working in the effluent and the smell is the hardest part of the job. once you get past the ick factor, and get on with the work, you will find its just another task that needs to be dealt with...
