How to Rebuild your Fart Filter

Hampton

Air Defense Dept
TECHNICAL Contributor
Nov 26, 2006
7,628
Panama City, Fl
Boat Info
2008 44 Sedan Bridge
Engines
Cummins QSC-500's
Straight Drives
Take Note of how it is secured in place so that you can add a PVC fitting without disrupting the re-installation, then remove it. Mine had two, easy screw on fittings, one at each end. It had a simple plastic strap around the middle where it sits in a cradle.

Take it to Home Depot. Buy a male and female threaded fitting of the correct diameter (2" on mine), and PVC cleaner and glue.

Go to a pet store and buy "Premium" activated Charcoal. Premium chunks are bigger and will allow better air flow. The crushed ones are cheaper but may cause a block if you allow one extra flush to foul it. Get some foam or aquarium filter material to plug the ends with.

Test fit the PVC fittings together and measure the distance inside that represents how much longer the fitting would make your filter (if making it longer will affect being able to put it back in) (seat to seat inside the fitting - 2" on mine). The connection on one end of mine goes right into the holding tank. On the other end, the vent hose turns 180 degrees after the fitting. Making the filter 2" longer could cause that line to bind or it may be too short. Making the filter too long could increase air resistance. Any blocking will cause the holding tank to blow up, potentially. That would smell bad.

Cut your filter in half where the fittings will not affect your re-installation. Cut out the extra amount as determined above if making your filter longer will affect reinstalling it. Clean it out, and let dry. Take note of fouling to satisfy curiosity. Remove label where gluing will occur. Sand both sides of both glue joints. Test fit parts. Clean with acetone. Apply PVC glue. Fit ends. Allow to cure.

Cut foam/filter material to fit in ends. Stuff that into the ends to hold the charcoal in. Fill both ends with charcoal. I put a thin piece of plastic over one end to turn it over to mate the ends. You'll need to leave enough room to screw the two halves together without compressing the charcoal too much. Slide the plastic out. Screw together. Check length. Blow through one end and ensure no blocking.

Reinstall. Smell the roses.

Next time, take charcoal and foam to boat. Take out, unscrew, dump out, replace foam and charcoal, and put back in. In my boat, this will take about 10 minutes and cost $5.

Today's expenses. $13 for charcoal, but used about 1/2. $3.50 for fitting. Already had foam and PVC glue.

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Thanks John. I won't waste another C-note at WM ever again.

Now, just before I cut my used spare open, how awful is the contents of the "fartified" old carbon filter crud??? Will I need a WWI gas mask?
 
Thanks John. I won't waste another C-note at WM ever again.

Now, just before I cut my used spare open, how awful is the contents of the "fartified" old carbon filter crud??? Will I need a WWI gas mask?

Ours was not working. It hasn't worked in the 3 years we've had the boat. I figured the PO soiled it. The foam looked like it had dirt on it, as did the charcoal. It looked like it had powdered dirt, but not too much. THERE WAS NO FOUL ODOR, but the charcoal must have been saturated (probably 5 1/2 years old). I think farts filter out into brown dust.

Realistically, I bet it was fouled many, many years ago.

I can tell you - it didn't work. That's for sure.
 
All: This is one of those "Get around to it" kind of things. Once I decided to do it, the job was complete in less than two hours including shopping and watching Texas get their asses handed to them.
 
I did the same mod and it worked great. One other thing is you can use a no-hub connector (2" at Home Depot) if your set up allows for it. It's basically a rubber sleeve with two clamps. I ended up having to do the clean out twice when I found out the pump out wasn't working correctly. The second time still sucked but was much easier. Took about 20 minutes.
 
Thanks for the step by step and photos! The world will smell a little bit better as a result of your work.:smt038

I plan to work on mine this winter. It was overfilled with water at one time and has never recovered!:smt013
 
Now, just before I cut my used spare open, how awful is the contents of the "fartified" old carbon filter crud??? Will I need a WWI gas mask?

I did mine a few months ago and was suprised that it barely had an odor at all. When it was still on the boat & the head was flushed, the stench was un freakin real. Since the refill......its all flowers!
 
John,

Thanks for the photos and the steps! I really need to do this too.. But mine is mounted on the hull side and my only reservation is that since this will make the filter longer , DOH I just re-read your post... Makes sense measure twice cut once...

Have you tried it out yet how does it work now??? LOL...



Thanks!!
 
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John,

Thanks for the photos and the steps! I really need to do this too.. But mine is mounted on the hull side and my only reservation is that since this will make the filter longer , DOH I just re-read your post... Makes sense measure twice cut once...

Thanks!!

Measure once, cut twice : )
 
Picture with the filter removed - see the cradle in the middle?

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Re-vitalized filter put in place. I got lucky. There was very little clearance between my fitting and the cradle in the middle. Look very close at the bottom, just left of the new fitting.

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