Charcoal filter on fuel tank vent??

PascalG

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Another great idea that causes more harm than good...

In the past couple of weeks, I ve had issues filling the tender fuel tank... had to go slow and no matter what I ended spilling fuel.

Traced the vent line and discovered an Atwood charcoal filter, proudly labeled "EPA compliant" on the transom behind the vent. Brillliant idea... of course after only 6 months the charcoal inside has solidified. Siding have a fitting to bypass the damn thing so I punched holes inside the element

I wonder who came up with this stupid idea... EPA? It's causing more harm from spilled fuel than vapors.
 
So when the charcoal is saturated with fuel vapors, can you light them like a charcoal briquette?
 
quote:

Originally posted by Gregory S

So when the charcoal is saturated with fuel vapors, can you light them like a charcoal briquette?






Yes, but only if you use "marine" matches. They're only $10 a piece and the first two are guaranteed to fail!
 
i have a charcoal vent filter on my HOLDING TANK.

Keeps the poop smell down if you are swimming around the vent.

are these intended for fuel system use?

RWS
 
"In the past couple of weeks, I ve had issues filling the tender fuel tank... had to go slow and no matter what I ended spilling fuel.

Traced the vent line and discovered an Atwood charcoal filter, proudly labeled "EPA compliant" on the transom behind the vent. Brillliant idea... of course after only 6 months the charcoal inside has solidified."

Yes - I had 4 of them on a large RIB and had the same issues. Had to remove them and splice in a clean line so not to have a mess at each fill up - good luck with yours.
 
And to make things worst, the brackets use a nut and bolt (top and bottom) to hold the canister but there I see no way to hold the nut in place, especially on the bottom bracket.

I hate charcoal filters on holding tanks, sooner or later they will clog up and a strong pump out station will damage the tank
 
if you can comfortably center the nut over the bracket hole, use a dab of crazy glue to attach the nut to the bracket (careful not to glue your fingers to the nut - latex gloves!) Once it's reasonably dry, you should be able to screw the bolt into the nut - when you cinch it up, the glue will break free, and the nut's accessible again.
 
My holding tank has a pressure relief valve built into the top. It has a foam filter and a spring with a flap. Only reason I knew it was there was because I was getting a faint tank smell in the cabin and someone recommended checking out this valve. Took it apart, dropped some screws in the tank, was able to drain tank and get screws back, still have the smell in my nose 6 months later. Fixed the problem.
Al
 
I had a similar problem with my Aquasport 2000 IO. I had problems with filling the fuel tank and had to disconnect the vent line from the filler cap (strange integral design vent/ fill fitting that apparently can allow rain water to enter the fuel tank under heavy rains), since it often spills gasoline into the vent line during filling.
Often I have to pressurize the vent line to clear out the accumulated gas. My mechanic told me that the design of the vent line has an intentional low point to reduce emissions. Instead it causes more spillage. I guess the newer ones have a carbon filter, hopefully not an intentional low point which can block filling as the fuel collects too high in the vent line.
 
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