Fuel vent dryer

[67hat34c]

Since we are now stuck with E-10 and having to retank, I have done some research. It appears that others are saying that the moisture being absorbed by the Ethanol is mainly comming from the fuel vent. Cant some type of dryer be added to the line to prevent some moisture from entering? I use dryers on my air compressor an it tends to work some. Since fuel vent is a rather slow volume it would appear that some type of dryer could be made to reduce the majority of the moisture.

Anyone have an idea?

 

[bobk]

I often considered doing this. There is a material that we use in laboratories that removes moisture from lines leading to vessels that need to remain dry. The lab grade is called Drierite, but a dry molecular sieve will also work. Drierite can be had with a color indicator to show when it needs to be changed. The idea would be to place a container in the fuel vent line that contains a pint of so of either dessicant in a long tube of say one inch diameter and attached in line in the vent. I'd say you want to place it high in the loop. You will need to make sure it doesn't get splashed by a burp during fueling.

I haven't searched, but it might be possible to buy an inline drier. There certainly could be a market for any gasoline powered equipment that sits idle for a long time.

Bob

 

[Jackman]

I don't think it would work. First, if you use a drying agent in line you would be decreasing the volume and capacity of the air flow required to successfully fill your tank without spilling fuel everywhere. Secondly, a drying agent like drierite is designed for enclosed containers/vessels that when closed obviously have a fixed amount of water. So in the boating application the drierite would probably not last long at all...enough to make it feasible even if you were able to maintain the proper airflow through the vent somehow.

I think the easiest way to avoid problems is to keep the tanks full and use the boat as much as possible...ie don't let it sit around for months without use.

Just my opinion....

 

[dougl33]

I know not everyone agrees with what he has to say, but Pascoe wrote an article on this a few years ago. I tend to agree with him in that most the water in your tank is pumped in from the fuel dock:

http://www.yachtsurvey.com/myth_of_condensation_in_fuel_tanks.htm

 

[doc g]

Ethanol is a scavenger for water. It is 5% water when they put it in the fuel to begin with. I believe that most water in the fuel tanks of boats comes from the deck plates which leak due to old o-rings and gen'l lack of good seal . I use a clear silicone grease on the deckplates to keep them sealed up tight and have not had any water problems in any of my boats . I have had problems with water in the tender's fuel though which I think was due to phase seperation of the ethanol from the gas. Once the already water saturated ethanol gets a bit more than it can absorb you can get phase sep problems. I think the only way to deal with it is thru filtration and dumping the water out of your fuel water seps regularly. The amout of water coming in thru your vents is in the form of humidity is not a problem,IMO ........Pat

 

[bobk]

I don't think it would work. First, if you use a drying agent in line you would be decreasing the volume and capacity of the air flow required to successfully fill your tank without spilling fuel everywhere. Secondly, a drying agent like drierite is designed for enclosed containers/vessels that when closed obviously have a fixed amount of water. So in the boating application the drierite would probably not last long at all...enough to make it feasible even if you were able to maintain the proper airflow through the vent somehow.

I think the easiest way to avoid problems is to keep the tanks full and use the boat as much as possible...ie don't let it sit around for months without use.

Just my opinion....

You are right, the volume occupied by the granular Drierite will reduce the volume of the vent system, unless you make the cannister wider than the bore of the vent hose. I guess you could also valve around it while fueling.

Drierite is used to keep the atmospheric vents of vessels dry. We also used to dry flowing 'house' air supplies with it. I'd think it will be adequate to dry the make up air to be dried. How often it would need to be changed will depend on humidity and amount of air coming into the tanks as the fuel is withdrawn.

Bob