[walteo]

Does anyone know where the filter is on a 1998 Mariner? I have looked everywhere and have removed every access point I can find. My marina neighbor would be very thankful for your assistance!!

[Mariners]

The Mariner did come equipped with a vent filter although one can be installed in the vent line located at the right side of the tank near were it exits under the galley floor.

[Funscape]

I recently had a problem with my 1999 350 mariner, while I was pumping out my black water tank the vent line for the tank suddenly started releasing the vacuum the pump was pulling. Is there a check valve that has failed or does the tank filter act as some sort of a check valve. The schematic from Carver doesn't show a filter or a check valve but something happened I have emptied the tank several times and never had this happen. Now when the toilet is flushed the odor if near this vent is very strong and I never noticed that before the vent started releasing the vacuum.

[K1W1]

Originally Posted by Funscape

.......while I was pumping out my black water tank the vent line for the tank suddenly started releasing the vacuum the pump was pulling.

Are you sure your black water holding tank is under vacuum when you are pumping out the contents?

Do you have an onboard Blackwater discharge pump or are you getting it sucked out from the marina system?

Originally Posted by Funscape

Now when the toilet is flushed the odor if near this vent is very strong and I never noticed that before the vent started releasing the vacuum.

Does air come out the vent line when you flush the toilet?

What kind of toilets and treatment system do you have onboard?

[NYCAP123]

Did you recently use it past the red light? If that is a vacu-flush there should be a filter, and it sounds like it needs replacing.

[Pascal]

the head type (VF or else) is irrelevant to the holding tank and filter...

if you holding tank builds a vacuum when you pump out, it probably builds pressure when you flush. This is a sure sign of the charcoal filter on the vent being clogged. Old age and/or moisture/overflowing. careful when you open the pump out fitting after flushing...

the filter has tobe on the vent line... follow the line to the vent fitting and you'll see it. Ideally it shoudlnt' be close to the tank top but higher up to make sure it stays dry.

They're about $80 from sealand, but yuou can make your own with a few PVC fittings and some charcoal (available at aquarium places...)

[Funscape]

Thanks everyone for your replys, my wife and I are new to the cruising style boats. Pascal I thin you hit the nail on the head with the filter, I looked inside the thru hull and can see a black something that I presume is the filter you speak of. I will be checking into it more this weekend. I now know it isn't supposed to have a vacuum when empting the tank. I gues that filter has been plugged for a while, we have only been the boat owners for a month.