Recommissioning the plumbing
SPRING RECOMMISSIONING
Pre-launch:
Check all your through-hulls and seacocks for signs of corrosion or other failure, lubricate and re-bed as necessary. Check all below-waterline hose connections and replace any cracked or broken fittings or corroded hose clamps. (And don't limit this exercise to your sanitation system!)
Faulty or failed electrical wiring or connections are the leading cause of boat fires. So check all your wiring and electrical connections...and your fuel lines and connections. Charge your batteries and make sure EVERYthing works...replace fuses as necessary...replace any frayed or corroded wiring or switches...any hoses that show signs of chafe. Go over every inch of your boat with a fine-toothed comb.
Bedding compound is a lot cheaper than replacing a waterstained headliner or repairing rotted fiberglass! So check all your deck hardware—rail stanchions, cleats, winches, etc—for signs that bedding is failing, and rebed as necessary.
If you haven’t done it in at least two years, change every impeller—in the electric toilet, the macerator, the engine intakes--on the boat, even if it looks fine. Each time an impeller pump starts up, it runs dry at least briefly which wears down the edges of the vanes. Unless it’s run dry long enough to really fry it, you can’t see the wear, and there’s only about the width of a human hair between an impeller that still fits tightly enough in the housing to pump water and one that doesn’t. Impellers also dry out over the winter and be come hard and brittle...they're more prone to failure in the spring than any other time. And a hard dry impeller can score the housing, requiring its replacement too.
If you have access to water, now's a great time to really CLEAN your bilge, sumps and chain locker--while the boat's out of the water and can really dry out. You won't smell them now, but there are a lot of odor-causing “critters” growing in all those places, just waiting to multiply and STINK when the weather get hot
If you haven't rebuilt your toilet in at least 3 years, now's the time to do it--while it's clean and dry. Preventive maintenance--new seals, gaskets, valves, etc--reduce the odds of having to make repairs by 99%. Whether you rebuild or not, if you didn’t do it in the fall, lubricate your manual toilet: open the pump and give it a liberal slathering with SuperLube—the same thick teflon grease that was in it when it left the factory. Not only will it keep your toilet pumping smoothly for a full season, but it will protect the seals and pump housing from grit and dirt.
Check all vent lines--on fuel, water and holding tanks--for obstructions and clean them out if necessary. Pressure test your holding tank for leaks. Check hoses for odor permeation and replace if necessary--it's a much more pleasant job in cool weather and when the system is clean and dry--than in hot when they're full of sewage. Clean or replace air valves in vented loops.
Post launch:
Test your toilet...make sure it's working correctly. Especially in electric toilets, things have a way dying over the winter. The time to find out is BEFORE you stock the fridge and head out for your first spring sail! Rinse ALL the antifreeze out of the system thoroughly with fresh water...but don't add any treatment to the tank until you're ready to use it. Put that down the head with the first "real" flush.
Don't forget the fresh water system! Follow the instructions in the "Fresh Water Maintenance" chapter for recommissioning your freshwater tank and plumbing to have clean tasting and clean smelling potable water all season. Make sure your water pump is working...and if not, rebuild or replace diaphragms and valves as necessary.
Others will add rigging and engine advice.