Getting rid of smelly toilets

Toilets  will get smelly after some time. But there are different causes and solutions.

1) Rotten egg smell (H2S) when flushing with sea water.
This comes from the dead critters on the intake side of the pump. You will smell this immediately when flushing.
I solve this as follows:

  • Close the through hull.
  • Disconnect the intake hose from the pump.
  • Get a piece of hose with a hose connector that fits the intake side of the pump and connect
  • Fill a bucket with chlorine. Put the temporary intake hose in the bucket and fill toilet.
  • Let it sit for 30 minutes.
  • Reconnect water intake and open valve.
  • Flush through several times.

2) Generally bad / pvc type of smell.

Toilet discharge hoses have additives in the PVC to make them soft and flexible. This aditive also makes them porous. Over time the hose will become smelly and needs to be replaced. This is valid for fresh water and sea water flushing.

When flushing with sea water the hose can get smelly already in an earlier stage.
Urine and Seawater  form calcium scales inside the hose. This will eventually block the discharge hose. Please read my post how to solve this when you act too late. The scaling smells urine like. It also effects the joker valves so you may find some dark discharge in your toilet bowl, if you do not use them a few days. Best way to solve this:

  • Fill bowl completely with vinager. You need about 3 liters.
  • Flush so that vinegar empties the bowl and fills the discharge hose.
  • Let it sit for two hours.
  • Flush a few times.

I suggest to do this several times a year to keep the dischage hose internally clean and keep the smell away.

You may also want to check for any leaks. Just one drop every now and then, generates a lot of bad smell. We had a badly cut hose end leaking at its connection. The trace of water droplets indicated a very small leak, probably not visible normally. It made the bilge and the area behind the drawer in the owners head, smell badly.