Comprehensive Reference for Marine Head Maintenance

Links, maintenance tips, videos and other resources to handle odors, clogs, and malfunctions

March 19, 2023

To prevent clogging and odors, slowly pump 1 pint of white vinegar (a single pump every 5 minutes) through the head and hoses once each month. Vinegar dissolves the scale deposits. Then flush the lines with 1 gallon of fresh water.
Never put anything in a marine head that hasn’t been eaten or is a small amount of marine biodegradable toilet paper.
Never use household drain cleaners or other chemicals.
Seals, O-rings, the pump rod, and walls of the pump cylinder can be lubricated with Teflon grease a few times per year.

Handling water leaks, calcification, blockages and odors (UK Boats.com)
Cleaning hoses, lubrication and odors (Boat US)
Marine toilets care and maintenance (Safe Skipper)

If the bowl fills when it is not being used or the toilet is not discharging properly, the problem is likely with the joker valve and it will need to be replaced.
The effects of different chemicals on joker valves (Practical Sailor)
VIDEOS: Replace a Jabsco Joker Valve (Xylem and Boatingtube)

If the pump displays a lack of suction, check that all hose clamps and o-rings are tight. The o-rings may need to be replaced if damaged.
Lubricate the discharge side of the pump by pouring mineral oil (or any lubricant specified for marine toilets) into the bowl, along with a little water, and pump through the toilet once per month. Lubricate the intake side by closing the intake seacock, disconnect the intake hose, pour oil into the hose, and pump the head.
Lubricate the piston rod with Teflon grease. Piston rod seals or o-rings that leak generally cannot be repaired and must be replaced. This leak is seawater or freshwater (depending on your toilet) and not wastewater, so the leak is not an emergency.
VIDEO: Repair Squeaking Jabsco Manual Toilet Pump (Xylem)
Head games: Troubleshooting marine toilets (Canadian Yachting)
VIDEO: Change the Jabsco Manual Toilet Base Valve Gasket (flapper valve) (Xylem)
VIDEO: Change the Jabsco Top Valve Gasket (Xylem)

If the head is clogged, pour two cups of 10% muriatic acid (available from hardware stores) into the bowl. After the fizzing reaction ends, pump the acid just enough to move from the bowl to the pump and let sit there for a few minutes. Then flush the lines with fresh water. Repeat as needed. If acid is not available, adding warm water to the bowl and leaving overnight may break the blockage.
Do not use household drain cleaners as these can damage marine hoses.
VIDEO: Calcium Removal from Marine Toilet, Sanitation Waste Hose Pipe and holding tank (starting at 3:55 on video) (Mothership Maintenance)
VIDEO: How to use a garden hose and valve to clear a blockage on a marine head discharge line (Kevin Carrigan)

10% solution of bleach and water should be poured into the holding tank to help keep it odor free and clean.
Check clogged vents that may result from overfilling the holding tank.

Ensure that all connections and seals are tight.
Check the discharge hose by rubbing a clean, damp cloth on the hose. If it has an odor, then the hose has deteriorated (the impermeable sanitation hose has become permeable) and must be replaced.
Preventive actions: If possible, flush with fresh water occasionally to remove sea water from the head and hose system. Pump at least 1 pump for every 1 foot of hose length. Flush enough to remove all of the waste from the discharge line; waste sitting in hoses and holding tanks without oxygen breeds anaerobic bacteria, which causes odors.
VIDEO: Eliminating Marine Toilet Odors & Stop Smells In The Head (SailingBritican)

Only use marine-rated biodegradable toilet paper that is designed to easily break down in water.

VIDEO: Boat Toilet Servicing - DIY Maintenance of the Jabsco Twist Lock Manual Marine Toilet (Mothership Maintenance)

“Boatowner’s Mechanical and Electrical Manual” by Nigel Calder
“The Voyager’s Handbook: The Essential Guide to Bluewater Cruising” by Beth A. Leonard
“This Old Boat” by Don Casey