Ethanol - A Slightly Different Question

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DavidInWilmNC

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I just installed a new Racor water separating filter last week. I'm using portable 6 gallon cans until I get the internal tank replaced. I'm also using all new hoses, and the carbs were rebuilt early this summer. Saturday, I drained both tanks and filled them with fresh gasoline from the station. Sunday, I took the boat out (with a '96 Johnson 90). It ran much better - smoother, little surging, didn't stall, etc - than it did last time. Before taking the boat out, I ran it in the driveway for about 10 minutes or so. There was a noticable amount of water in the clear part of the filter. I wonder if the station has contaminated gas. It's an 'off-brand' station, so I'll try a BP / Amoco next time. When we had it oun the water, it ran well, but wouldn't rev over 4000. It didn't seem to have as much power, either.

I know ethanol has a greater affinity for water than it does for gasoline. What happens to this ethanol when it goes through the water separating filter? Is the ethanol filtered out with the water or does it pass through the filter with the gasoline? If so, I'm wondering if I'm actually seeing a higher concentration of ethanol in the gas than I would normally. I know ethanol has less 'power' than gas, so I'm wondering if this could be the cause of my motor's sluggish performance / reduced power.
 
dingbat

dingbat

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Re: Ethanol - A Slightly Different Question

The first thing that come to mind is did you change the hoses out before or after you drained the tank? If before then there is a good chance you had some old, water logged fuel still in the hoses. Then again it could mean that you didn't get all the water out of the tank or go picked up some water at the service station. BTW: Brand names stations pass just as much water as none brand name stations. My only bout with water in 3 years came when I got a slug of water from a ?brand name? station.

A fuel separator works on gravity. The heavier water molecules settle out of suspension and fall to the bottom of the filter for collection. When water bonds molecularly with the ethanol they form a heavier molecule and are captured in the fuel filter.

The problem here is that the ethanol that combined with the water and settled out in the filtersis used as an octane booster. Without the ethanol you're burning sub octane fuel which can have catastrophic results on a motor.

FWIW: Stratron is not going to do one bit of good if you get free water in the system. Its helps with condensation but will do nothing if you end up with "free water" in the tank. The only way to resolve a "free water" issue is to drain the water from the bottom of the tank and start over.
 
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DavidInWilmNC

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Re: Ethanol - A Slightly Different Question

A water separating filter causing engine damage due to reduced octane? Hmm... I thought these filters were supposed to help!

One of the hoses was new (right out of the pack) and used only after the filter. The other piece was shorter and was drained when I disconnected it prior to installation.

I have had problems in the past with fuel from several off-brand gas stations. I have used BP/Amoco exclusively in my cars since the mid '90's and have never had any issues with fuel. I'll drain the tanks again and use that gas in my van. I'll leave the caps off the tanks to let any moisture evaporate. I'll drain the hoses and pump a few 'squeezes' of gas from the freshly filled tanks to purge any possible moisture or bad gas from the hoses. Of course, I'll drain, prime, and purge the filter with fresh gas as well. I'll also hunt town some ethanol-free gas and fill the tanks with that.

It's gonna be a couple of weeks before I get the chance to take the boat out again, unfortunately! If I still have fuel problems, I'm gonna give up!
 
Silvertip

Silvertip

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Re: Ethanol - A Slightly Different Question

Where are you folks from that are gathering that much water. Good grief, we've been using E10 in the midwest for well over a decade and this is simply not an issue. You should not feel any difference in how the boat performs using regular grade gasoline vs regular grade gasoline that is an ethanol blend up to 10%. In the referenced post a person commented "I wonder how many cars will be froze up this winter due to the water in the fuel". For heavens sake folks, fuel system deicer is isopropyl alcohol (and variations). Ethanol is "corn squeezins". You can't hardly sell fuel system deicer up here in the midwest because it is no longer necessay. Ethanol is an excellent fuel system cleaner as well so if you've neglected the fuel system over the years by NOT using Star Brite, Sea Foam or any other fuel system treatment, Ethanol will create a problem for you on older engines and those older engines that were built with non-ethanol tolerant rubber and plastic parts. High quantities of water in fuel is being "picked up" not condensed in the tank unless it has sat for very long periods of time. High quantities being the operative word.
 
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DavidInWilmNC

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Jul 20, 2009
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Re: Ethanol - A Slightly Different Question

Coastal NC.

As stated above... I took two totally empty 6 gallons tanks, filled them on Saturday, installed new fuel lines and drained a 2' section of 6 month old line, installed a new Racor filter, ran the motor for about 10 minutes, and had a very noticable amount of water and ethanol in the fuel. Where's it coming from? That's a question for the distributors and gas stations I suppose. I did this to eliminate any posibility of water being due to 'a neglected fuel system'.

As for water freezing in the fuel lines... that's not going to happen. There's too much damned ethanol in it to freeze! I pumped the remaining fuel from my internal tank a couple months ago. It didn't look too bad at first. After I let it settle for a while, it looked like oil and vinegar salad dressing. Afte a few days, the amount of water seemed to sort of stabilize. I put it in the freezer to see if chilling it had any effect. A bit more water settled out, but it still won't freeze in a -5? freezer due to the alcohol.


Silvertip said:
Where are you folks from that are gathering that much water. Good grief, we've been using E10 in the midwest for well over a decade and this is simply not an issue. You should not feel any difference in how the boat performs using regular grade gasoline vs regular grade gasoline that is an ethanol blend up to 10%. In the referenced post a person commented "I wonder how many cars will be froze up this winter due to the water in the fuel". For heavens sake folks, fuel system deicer is isopropyl alcohol (and variations). Ethanol is "corn squeezins". You can't hardly sell fuel system deicer up here in the midwest because it is no longer necessay. Ethanol is an excellent fuel system cleaner as well so if you've neglected the fuel system over the years by NOT using Star Brite, Sea Foam or any other fuel system treatment, Ethanol will create a problem for you on older engines and those older engines that were built with non-ethanol tolerant rubber and plastic parts. High quantities of water in fuel is being "picked up" not condensed in the tank unless it has sat for very long periods of time. High quantities being the operative word.
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