Fuel Polishing

Swee Pea

New member
I have read the past threads on fuel polishing. I am putting one together to clean out my fuel tanks; I plan to draw fuel directly frm each tank, but I am a little "dense". Does the 12v fuel pump go before the separator and "push" fuel through it or does it go after the separator and "pull" fuel through it? Or does it matter?

Be kind. :oops:

Happy 4th of July!

John
SweePea
 
Most people have the pump pull the fuel through the filter so the pump is handling clean fuel...
But in general, pumps push better than they suck...

If I were designing your recirculating design I would have a coarse screen and a water separator at the intake of the pump just to keep nasty stuff from passing through the pump and the high micron final filter on the out put side of the pump... No one else does it this way, that's just me...

Now, putting on my propeller beanie and wrapping my white scarf around my neck, I'm off!

denny-o
 
Is fuel polishing a process for gas fuel as well as diesel? I didn't know it was done on gas. Would that take care of the fuel destabilization due to the ethanol content causing water absorbtion?

Harvey
SleepyC :moon
 
hardee":2myvvhyc said:
Is fuel polishing a process for gas fuel as well as diesel? I didn't know it was done on gas. Would that take care of the fuel destabilization due to the ethanol content causing water absorbtion?

Harvey
SleepyC :moon

That's somewhat of the idea. Dr. Bob showed a picture of how he polished gas, as they do with diesel. I am trying to clean the gas tanks and "polish" the fuel by removing the crud and water from fuel that has been stored for a while in the gas tanks on the boat. As we know, the high content of alcohol in the ethanol causes water to accumulate. I have an inline fuel separator, but when that gets gunked up, its usually when you are on the water and is no fun.

So, when fuel is in the tank for a period of time, tanks not full and temp changes cause condensation, or whatever, you can "polish" or use a 12v fuel pump and a fuel separator to clean the fuel of moisture and crud, allowing less stress on the inline system.

I bought a 12v fuel pump with an inline pre-filter (100 micron) which will suck the gas out of the tank and push it through a 10 micron fuel separator with a clear viewing bowl. Do this a few times and treat the fuel and your engine will be exposed to less contaminants. (at least thats the theory)

You gotta ask the guy with the beanie and the propeller to see if I got it right. Dr. Bob is "On The Road Again" (Willie Nelson at the Guitar) :wink:

John
Swee Pea
 
John,

No beanie and no propeller here, just a dumb chemist with test tubes in his ears!

I am curious how one might separate water from fuel that has absorbed more water because of the alcohol, except by repeatedly extracting it from the bowl of the fuel filter system as a separate layer. I've heard of folks rinsing the tank with pure alcohol (methanol or ethanol) to solublize any water layer left after the gasoline (etc.) has been pumped out, and then re-inserting fresh gasoline once the tank is free of water. Is that what you have in mind?

I don't think there is any practical, economical way to draw the water out if the gas/alcohol/water mixture is all one layer and the water has not layered out.

Am I missing something here?
 
Hmmm. Your response, Dave, makes me beg the question: why not use a large filter (same principle as in-boat filter, on a larger scale).

Warren
 
Beats me. I just read the posts and figured that the fuel separator separated the water from the fuel; the increased ethanol content attracting and holding water in suspension in the fuel. As the fuel is pumped from the tank and goes into the separator, the water/moisture is separated out and goes to the clear bowl where it is discarded. Recirculating the fuel several times may help reduce moisture content.

I am probably not following your question/response, but its the best explaination I've got. If Dr. Bob was on line, he would be able to explain better than I could.

Heck, I just wanted to know which side to put the pump on! :roll:

John
Swee Pea
 
John,

The separator/filter should accumulate water in the lower part, but if you have a lot of water, it might be several filters down the road before you get it clean. Try one for a couple gallons and see what is in the bowl. If no water, just keep going, until the filter quits working (assuming there is crud in the system) and renew. If the bowl fills with water, then likely the filter won't pass fuel very well, is my SWA guess.

It might be you need to make two passes on the fuel to get it free of water. Some fuel drier in the tank when you recharge it for the last time would help remove traces of water, also.

No matter how you slice it, the job is a PITA.
 
I use a Mr Funnel when adding gas to remove debris but cant state how well it removes water
see
http://www.mrfunnel.com/Mr._Funnel/Models.html

I bought from Harbor Freight for $12

Be careful pumping gas, work in a well ventilated area and have safety items close by. Gas fires are very difficult to fight and 10 micron fuel and water filters (RACOR) are inexpensive
m2cw
 
Seperator filters with the clear bowl let you know what is in your system. One time when I siphoned the fuel out of my tanks I saw there was water entering the filter bowl from the bottom of the tank. I poured the water out of the bowl, poured some clean gas into the tank and siphoned the tank again. After doing this cycle three times I have never seen any more water in the fuel. I suspect it come in through the fuel vent.
You can siphon the tanks by removing the fuel line from the outboard engine, pushing a small sturdy piece of plastic into the end of the fuel line fitting to hold back the check ball and initating the siphon by squeezing the fuel bulb. Note, the check balls operate by gravity so pay attention how you hold the bulb.
This is a slow operation but it shows you can get the job done with just good filters.
 
Ahhh jeeezzzz, someone has to be the prophet of doom here and no one else has stepped up to the plate - why does it always have to be me? (mumble, grumble)...

If you are polishing gas be daggone sure the pump you are using is sealed and rated for high flammables such as gas... Now, most pumps advertised for pumping diesel are likely safe, but with the proliferation of cheap imports/copies, you need to look closely... And be sure the switch or relay that controls the pump is either sealed or separated far, far away from the fumes, or both...

Well now, looky there - I got my nagging quota done for the month and it is only the 5th already....
 
The pump I am using is a gasoline fuel transfer pump, specifically designed for pumping gasoline - got that covered. I bought a sealed in line on/off switch factory wired on a 10' wire and wired the pump with an insulated connector to the 10' wire. Got that covered. The only "violation" is the alligator type connector to the battery, which can spark. I figure the battery will be far enough away and polishing will occur in open air, not an enclosed environment.

Any other suggestions are always appreciated.

John
Swee Pea
 
Here's the problem with trying to polish gasoline containing ethanol.

Gasoline and water don't mix. Pure gas (no ethanol) with water in it results in the water forming a layer under the gas. Filtering with a gas/water separator works fine.

Now when ethanol is added to the gas, it mixes totally, with no separate layers forming.

When water is added to the gas/ethanol mix, the ethanol mixes totally with the water, and with the gas, which results in one mixed fluid, with no layers. This fluid (water/ethanol/gas), will go right thru a filter/separator without removing the water.

If too much water gets in the gas/ethanol mix, the ethanol mixes with the water and the water/ethanol mix separates from the gas forming a layer of water/ethanol under the gas.

This is a very dangerous situation for the engine. If the fuel pickup sucks up this water/ethanol mix and sends it to the engine, the engine can suffer damage. Two stroke engines can be destroyed by burning water/ethanol. That mix removes the lube oil from the crank bearings/pistons/rings/cylinder walls and the low octane caused detonation. The same low octane/lean burn can also damage a 4-stroke engine.

So polishing gas/ethanol/water will only remove particles and crud, but will not extract the water from the mix.

Pumping a sample from the bottom of the tank and putting it into a clear container (glass-be careful) can show if there is any free water/ethanol under the gas mixture. If this is the case, I would empty the tank completely and start over with fresh gas with stabilizer added.

Since water and ethanol mix completely at any mix ratio, there is no easy way to remove the water from the ethanol.

This is why adding ethanol to gasoline is a bad idea for marine engines. Its not really a good idea for land vehicles either, but the fuel in a car/truck is used up more often and less problems result. However, if a car/truck/generator/mower/etc is stored, stabilizer should be added to the gas.
 
I guess what I will be doing then is cleaning the tanks of sludge and water that has separated from the gasoline. When our on board fuel separators accumulate water, what you're saying is that this is excess water that could not be dissolved in the ethanol enhanced gasoline, and has moved to the bottom of the tank. Or it is water that was not dissolved, not moved to the tank, but is in suspension with the gasoline and enroute to my motor.

Does the Startron really do what it says it does ('Ethanol / E10 fuels increase the amounts of water and sludge in your fuel tank. Star Tron breaks down this excess water and sludge to sub-micron size allowing it to be safely burned away during normal engine operation.
Therefore Star Tron prevents phase separation and fuel gelling, eliminating ethanol fuel problems"
)?

Does any product take the moisture out or separate water out of ethanol enriched fuels?

Inquiring minds want to know? :?: (Can tell I didn't do well in Chemestry 101)

John
Swee Pea
 
I guess what I will be doing then is cleaning the tanks of sludge and water that has separated from the gasoline. When our on board fuel separators accumulate water, what you're saying is that this is excess water that could not be dissolved in the ethanol enhanced gasoline, and has moved to the bottom of the tank. Or it is water that was not dissolved, not moved to the tank, but is in suspension with the gasoline and enroute to my motor.

If you know that you are running ethanol/gas then the water in the separator is excess to what the alcohol can dissolve. In many years of running my C-Dory, I never had water in the separator, but my fuel vents were located in the splash well not outside the hull. Could you be getting salt water into the vents?
I don't know if salt water will dissolve in ethanol.

Does the Startron really do what it says it does?

I never used any, so I can't say.

Does any product take the moisture out or separate water out of ethanol enriched fuels?

I would like to know the answer to this too!
 
So far, Larry gets the bonus points from my mechanic. :thup (first to mention stabilizer). After 2 sessions of carb work :cry by the Yami Doc's, we came up with a fuel treatment program. >>> FUEL STABILIZER in every tankful. :roll:

What they brought from the Yamaha school was simple, less expensive than carb rebuild every year, and less work, and maybe safer, than polishing gasoline. :thup :)

Into every gas fill, mix the storage dose of blue Marine Stabil. Then also, add the Startron, (and I do this at the storage or initial treatment dose also) in stead of the weaker dose. So far, starts every time, first time, and runs smooth. No water in the separators. :idea:

Works for me, YMMV. Good luck and keep your head down when you take that allegator clip on and off. :twisted:

Harvey,
SleepyC :moon
 
Yowsa on the stabilizer, Blue version Stabil here, an ounce for every five gallons.

Three seasons of use and a couple hundred hours down the road (five hundred gallons of gas, maybe?), and I've never had a problem with Oregon's E-10 gasoline in my inboard. With my boat's aluminum tanks, and storage in Oregon's wet, cool coastal climate, it should be a poster child for water in the gas, but no problem no problem, no problem.

Not sure about this, but I think Stabil helps prevent separation by emulsifying the two phases and gets ahead of the problem. Frank might know better about that.

[Still on the original filter, too!]
 
The ethanol can only hold a certain amount of water bound to itself... You cannot separate the alcohol bound water by crude mechanical means such as a water filter, but you will remove the free water, plus the rust, gunk, etc... So polishing is still worthwhile IF you have issues with the tank or the load of fuel being contaminated..
 
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