DRAGONFLY Trimarans User Forum

The level gauge for my blackwater tank ceased to indicate although there was power to the sender unit. I plucked up courage yesterday, removed the six screws and lifted the unit out of the top of the tank. The sensor is contained in a cylinder measuring about 4" long and 2" in diameter. It has many small holes, almost all of which are blocked by a white (white?!) substance which has the consistency of silicone sealant. There is no evidence of manufacturer or part numbers. Has anyone been able to repair or replace this unit?
Mike Paterson
Df1000/34 Champus

The white "silicone like" substance blocking the holes might be soap residues.
The residue probably feels "greasy".
Have you tried cleaning the holes? It might be all there is required.

You have to clean both: net and the floater - look at the pic.

Please click on any of the photos to see them enlarged!

Thanks to you both.
Mario, I'd like to see what it should look like but your pic hasn't shown up. I suppose the best cleaning medium would be dilute bleach.
Mike Paterson
Df 1000/34 Champus

I've just put the picture in the Mario's message.

parkhouse wrote:I suppose the best cleaning medium would be dilute bleach.

Would filling the holding tank with water and adding bleach be safe for the hoses, etc?

EarthBM wrote:

parkhouse wrote:I suppose the best cleaning medium would be dilute bleach.

Would filling the holding tank with water and adding bleach be safe for the hoses, etc?

Bleach is a strong corrosive that will attack metals and might affect other parts, especially in the toilet. It will also kill ALL the aerobic bacteria and that will greatly increase odor.

I just performed this unpleasant task: removed the whole unit and washed it in HOT soapy water with an old toothbrush and a piece of wire. I let it soak for a while and was able to wash out everything. Not difficult.

I estimate about a cup full of hard residue came out from the unit.

As Larry pointed out, you should never put bleach or any other strong agents into the holding tank or toilet. I recommend K.O. (Kill Odors) and C. P. (clean potties) - two related products as well as Odorloss to keep the system reasobaly clean and less stinky. Nothing appears to prevent the eventual build-up of hard stuff in the sender...

BTW, I now use only fresh water to flush the toilet. It reduced the smell a lot. We just carry a few (2-3) empty 1 gallon water jugs and refill them with fresh water regularly.