If you’ve read the perilous potty then you know we’ve had problems with our marine toilet on our sailboat.  While messy it was easy to fix.  I’ve had several people looking for answers on fixing a marine toilet so I’ve been doing some research.  Thus a series of articles will follow this one.

Odors:  The most common source of an odor is a leak.  Here are the less common sources.

1. The permeable hose.  Take a rag and rub it over the hose and then give it the ’sniff’ test.  If the rag stinks then the hose is permeable and needs to be replace with the correct hose.
2. The vent is clogged on the holding tank (we had that problem).  This is something that usurally happens when you over fill the holding tank.  It pushes the solids up to the vent.  When ever possible, we back flush the vent when doing a pump out.
3. The discharge valve is defective.  This can result in raw sewage backing into the toilet bowl.  You may not know it as the water in the bowl may look fine.  But bacteria will cause the bowl to stain quickly.
4. Your O-ring is worn or maybe the piston rings on a manual toilet if there a double-acting piston.  This could let sewage work into the flushing side of the pump.  You probably need to rebuilt the pump.
5. Marine life could be living in your flushing water.  If you’ve a ‘rotten egg’ smell then this maybe your problem.  Consider installing a raw water strainer on the suction line seacock.  Check it often as you may need to clean it out.
6. There could be a low spot in the vent line.  Which can collect liquid, like the trap on a sink drain.

Buildups:  You can get a buildup similar to what you find in a drip coffee maker on discharge valves, seacocks, and lines.  If it’s really bad it can plug your toilet.  If it’s been getting harder to flush or been clogging or if you’ve had leaking back into the bowl, you might have a calcium build up.

I use household white vinegar on a regular basis about once a month during the season we boat.  I use about 2 cups and pump it through to the holding tank.

If however, you are really having a problem and that doesn’t help then you might need to try Muriatic (hydrochloric) acid.  You can get it at most marine and hardware stores.

Use about a 10% solution in the bowl and be sure to pay close attention to all the warning stuff on the bottle!  It should ‘fizz’ as it works.  When it stops fizzing pump the bowl almost dry.  Give it  a few minutes and then pump a few more times.  Keep doing this until the entire discharge line has been cleaned.  Flush our well to remove any of the remaining acid.  Side note: this acid will also attack metal parts much more slowly.

If this doesn’t work then you may need break down the toilet and chip out the buildup.  I’d replace the hoses.

Plugging up:  Marine toilets use very little water and clogging up is a very common problem.  The pumps, valves and impellers just can’t handle solids, as was part of the problem we had.  Be sure to use Marine/RV toilet paper and never put anything down the toilet that hasn’t passed through the human body.

Never try to use a drain cleaner to clear a plugged toilet.  The parts are very sensitive and you can cause a great deal of damage.  You can try adding warm water to the bowl and leave it for the day or overnight the solids may break down enough to pump out later.

Although sooner or later we’re all faced with the task of a stubborn plug and end up having to take the toilet apart.

Please remember to help out below if you can, thanks!

Read more on how to winterize your head ‘click here’

Read more on how to pump out the head ‘click here’