Green Crystals in Fuel Filter

[philiefay]

After having fuel starvation issues I have switched out my fuel filter on my 9.9hp outboard 3 times recently. The first couple of times i was out sailing/ motoring and I switched each filter out a day apart......he 3rd time I cut the filter open and found green crystals in the filter (see attached). Keep in mind that less than 3 gallons of fuel has ran through the lines and the filter. I syphoned out the fuel from both tanks through a filter and there was a small amount of brown sludge left in the filter. I then attached a clean rag to a stick and drained every drop of fuel and small dark particles that I could see in both plastic 3 gal fuel tanks.

They appear to be completely clean now, though I cannot clean the lines effectively.

Prior to this the engine ran flawlessly every weekend for months. I am curious if anyone has experienced this issue? Perhaps is was a bad batch of fuel? Maybe I should filter fuel when filling the 3 gal tanks? Maybe the fuel had a higher ethanol content? I just don't know so looking for suggestions.

 

[senang]

Somebody put sugar in your fueltank? Sugar is a known sabotage act of petrol engines.

 

[kloudie1]

Going to guess a bad batch of gasoline, since it was in the plastic can before getting to the engine.. a slightly educated guess might be that the gasoline came from an underground tank that had recently been filled which stirred up some water/algae/schmutz that got to you.

 

[thinwater]

Gasoline additive?

 

[rgranger]

Are the cyrstals soluble in water? Have you tried putting one on the tip of your tonge? It is not recommended but I definitly would have.

 

[philiefay]

So today I pulled the fuel lines off and cut them at the hose clamps. Pushed a rag through like cleaning a rifle and it got stuck in one of the two lines. I filleted the line in 1/2 to see and was blown away by the amount of build up considering that the 3 gal tank showed no such signs. See attached photos. Line has been replaced, filter replaced again and I ran the engine for about 30 mins with no issues.

The black photo is the compression bulb cut in 2. The other line was completely clear. The prior boat owner was in Oklahoma. I know almost every crevice of the boat had dirt dobbers, cant imagine how something like this could build up other than bad fuel.

 

[dlochner]

Well, the mystery of the fuel starvation is solved. Now for the next mystery, what is that stuff. Maybe one of our resident chemists would like a sample to analyze.

 

[SycloneDriver]

I've never see that before. Wow!

I would put a few a small sample in water and see if it dissolves. I would also put a small sample on a hot pan and see if it melts. Looks like sugar or salt to me.

 

[rgranger]

That is not dirt or bacterial growth. It would not be crystalline if it were. Somebody added a salt or a sugar-like compound to your gas. Is there an odor associated with the cyrstals?

 

[mikeracca]

So, I see your fuel lines are grey… how old are they? The reason I ask, is SeaDoo and other water sports craft used these grey fuel lines back in the 90’s and early 2000’s that were not suitable for fuels with ethanol. Here in WA we have been using 10% ethanol since 91/92 ish. The fuel lines took a few years to deteriorate to the point yours are now, but it would happen. And the crystals could easily be the ethanol crystallizing. It’s possible it’s sugar, but sugar doesn’t usually turn green. Brown yes green no. When I see green sludge or crystals in grey fuel lines I think about all the Seadoos I have fixed over the years.

 

[rgranger]

And the crystals could easily be the ethanol crystallizing.

NO!

Maybe the ethanol evaporated and what was dissolved in the ethanol crystallized but ethanol is a liquid at room temperature ..... You would need to be at -174F to crystallize ethanol. The green could be a lot of different trace contaminants....

 

[thinwater]

The green is from some manner of dye or copper corrosion products. A red herring.

I've been in the fuels industry a long time, and this is different. But if I look at the crystal form, it looks like it could be sugar to me. (this is rock candy) I would try dissolving them in water. Makes no sense, but perhaps somebody didn't like somebody.

 

[JamesG161]

NaCl crystal is the only crystal known to have a perfect Crystal shape of a Cube.
Its color can be contaminated with other items, but rare.

My guess Sugar crystals.
Jim...

 

[mikeracca]

NO!

Maybe the ethanol evaporated and what was dissolved in the ethanol crystallized but ethanol is a liquid at room temperature ..... You would need to be at -174F to crystallize ethanol. The green could be a lot of different trace contaminants....

What is found in the bottom of carburetors left full of fuel after the fuel evaporates is what I was referring to. I usually only see very small crystal like deposits that turn to powder with the slightest touch. This wasn’t a thing with non ethanol fuels, that would turn into a dark brown jelly that smelled like old paint. Usually referred to as lacquer.

 

[rgranger]

The green is from .....(snip)..... or copper corrosion products. (snip)....it looks like it could be sugar to me.

 

[thinwater]

What is found in the bottom of carburetors left full of fuel after the fuel evaporates is what I was referring to. I usually only see very small crystal like deposits that turn to powder with the slightest touch. This wasn’t a thing with non ethanol fuels, that would turn into a dark brown jelly that smelled like old paint. Usually referred to as lacquer.

The powder is not from ethanol fuel per se, those are aluminum corrosion products from the bowl.

This is why an anti-corrosion additive is eccencial with e10. Biorbor EB and Stabil 360 MArine (not the red stuff) have done well well in independent testing (most are snake oil).

 

[rgranger]

The powder is not from ethanol fuel per se, those are aluminum corrosion products from the bowl.

Yup! The gas in the carb bowl evaporates first leaving ethanol. Ethanol is hygroscopic and picks up water from the air and when the ethanol evaporates, you are now left with a few drops of water in the bowl... and that corrodes metals.

It is a good idea to add a fuel shut off valve and then run your engine dry after each use. That will eliminate both the "terpentine" residue from pure gas as well as water sludge from E10 from ever building up in your carb's bowl.

 

[philiefay]

It was not sugar, It did not dissolve in hot water. Also, I have seen extensive comments regarding the break down of the grey fuel hoses. These hoses did not breaking down at all. I decided to only use premium gas from now on to avoid any gumming up in the carb.

 

[Timm R Oday25]

Somebody put sugar in your fueltank? Sugar is a known sabotage act of petrol engines.

Sugar in gasoline is an old wive's tale. Myth Busters actually did a segment on it . They used an old Cadillac motor . The sugar caused no harm whatsoever .Then there's the fact that plain old sugar does not dissolve in gasoline. It just sinks to the bottom of the gas tank. A University of California, Berkeley researcher tested this myth experimentally way back in 1994 by putting sugar into gasoline and then spinning it in a centrifuge. He measured how much undissolved sugar spun out of the fluid and then calculated how much sugar remained dissolved in the gasoline. It was less than a teaspoon for 15 gallons of gas – more than a full tank in many cars. Even if you have less than a full tank and someone dumps sugar in there, the fluid can only incorporate so much sugar. You'll just have more undissolved sugar sludge at the bottom of the tank. Annoying for sure, but not damaging the engine.

 

[thinwater]

Yup! The gas in the carb bowl evaporates first leaving ethanol. Ethanol is hygroscopic and picks up water from the air and when the ethanol evaporates, you are now left with a few drops of water in the bowl... and that corrodes metals.

It is a good idea to add a fuel shut off valve and then run your engine dry after each use. That will eliminate both the "terpentine" residue from pure gas as well as water sludge from E10 from ever building up in your carb's bowl.

No. The ethanol evaporates first (check the boiling points of ethanol and gas [final boiling point ~ 400F]--big difference). I have run many gas evaporation tests.

It really is NOT gum or tepentine in modern fuels. It is corrosion from water absorption, and no, drying is NOT required. The water makes the ions mobile withing the fuel. A good anticorrosion additive will stop this. Keeping the fuel dry by closing the the portable tank vent also works well. Protect the tank so that the vent is safe from spray and rain.

I'm pretty sure, having participated in ASTM standards and test development for additives.