Warning....Test your own gas

grego

Petty Officer 1st Class
Joined
Dec 12, 2008
Messages
328
Re: Warning....Test your own gas

I asked a buddy that works for a fuel co. He said this " gasoline without addtitives will get you better mpg. The idea that ethanol does, absorb water, which adding water to fuel makes for a higher compression, This evens out the difference in mpg "in theory" BUT! the fuel caps are a pressure "release" set up" He said, that to accumulate any measurable amount of water would take a lot of time.
 

puddle jumper

Captain
Joined
Jul 5, 2006
Messages
3,830
Re: Warning....Test your own gas

160 pickups in the fleet and you replaced 300 pumps last year???? That on average is nearly two per vehicle. If water is causing the fuel pump failure someone is pouring it into the tank. I just don't believe that claim -- sorry!

We have checked into many different possibilities and I am sure that all of them were not caused by just the fuel. I think often the fuel caps are being left off in the rain and or the tanks are not being cleaned properly. The problem is the fuel is the only constant problem. I have been told that just an ounce of water in the fuel tank can destroy a fuel pump in these new fuel injected trucks. I am not the only one diagnosing these problems. Most of the trucks with problems only use about a tank full every month or so.

Its not that uncommon up here to have 80% to 95% humidity in about 30degf to 50degf for weeks at a time.

Just ask the been counters as they let me know about it all the time.
 

fwoodtx

Cadet
Joined
Jun 7, 2009
Messages
9
Re: Warning....Test your own gas

We have checked into many different possibilities and I am sure that all of them were not caused by just the fuel. I think often the fuel caps are being left off in the rain and or the tanks are not being cleaned properly. The problem is the fuel is the only constant problem. I have been told that just an ounce of water in the fuel tank can destroy a fuel pump in these new fuel injected trucks. I am not the only one diagnosing these problems. Most of the trucks with problems only use about a tank full every month or so.

Its not that uncommon up here to have 80% to 95% humidity in about 30degf to 50degf for weeks at a time.

Just ask the been counters as they let me know about it all the time.

Why don't you put water separator filters like Racor on your trucks? I would think they would pay for themselves relatively quickly in less replacement of those fuel pumps. The Racors have the clear bowls and you can see if there is water in them.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Warning....Test your own gas

I still gotta dissagree with Dingbat AND silvertip.
maybe you folks just dont see many hulls that hold 100 plus gallons that tend to sit months at a time here in a relativly warm and very humid place.
here we are seeing E fuels do nasty stuff.
yes I have the testers and yes we do fuel samples and yes once phase seperation occurs the ENTIRE gasoline supply in the tank is bad and WILL destroy a motor.
why do you think the farmers in the midwest are exempt from having to use E fuels in farm and industrial equipment.
why do you think the FAA has an outright BAN on ANY e fuels in aircraft.
E fuels will work,although way more costly, in most automotive applications due to the fuel turnover rate.
but even with various stabilizes such as stabil blue,startron blue and USA gas shock we still see phase seperation in as little as 60 days.
I have some pics of recent fuel samples I need to post.
in one of the cases the fuel is from the same marinia I work out of with over 500 boats on the lot and sometimes the fuel gets contaminated rapidly.
on the subject of filters.
ya gotta remember that the alcohol molecules interlace with the larger hydrocarbon molecules, the water molecules interlace with the larger alcohol molecules. until the heavier alcohol water mixture falls out of solution.
however while its suspended in a solution it simply CANNOT be filtered out with a standard filter or water seperator.
if the filter media was made small enough to block water molecules it will block both the larger alcohol molecules and the even larger hydrocarbon molecules.
a quick demonstration can be done in the average kitchen.
dissolve 3 table spoons of sugar in 1 pint of boiling water.
poor the SOLUTION through a coffee filter.
how many tablespoons of sugar REMAIN in the filter.
there are many many pages of reading from BRP,Yamaha Brunswick and Volvo on the nastiness of E fuels in this industry and the problems to come if they allow E20 fuels.
then go look at WHO is pusing E sales and why.
CNG makes so much more sense than corn
 

WAVENBYE2

Lieutenant Commander
Joined
Apr 28, 2007
Messages
1,636
Re: Warning....Test your own gas

Very interesting, I am going to test it out just for the curiousity of it.
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: Warning....Test your own gas

I asked a buddy that works for a fuel co. He said this " gasoline without addtitives will get you better mpg. The idea that ethanol does, absorb water, which adding water to fuel makes for a higher compression, This evens out the difference in mpg "in theory" BUT! the fuel caps are a pressure "release" set up" He said, that to accumulate any measurable amount of water would take a lot of time.

I agree with him, but he is talking about an automotive fuel system. I have read plenty of articles explaining how a car's fuel system is slightly pressurized, and that reduces the chance of ethanol being in contact with moisture.

Having said that...a boat's fuel system is vented to the atmosphere, and the water issue is very real because of that fact. Especially here in the rain, and humidity, of Florida!

Happy (ethanol free, I hope) boating!
 

puddle jumper

Captain
Joined
Jul 5, 2006
Messages
3,830
Re: Warning....Test your own gas

Why don't you put water separator filters like Racor on your trucks? I would think they would pay for themselves relatively quickly in less replacement of those fuel pumps. The Racors have the clear bowls and you can see if there is water in them.[/quote)

The problem with this, the fuel pumps are in the fuel tank not like the old mechanical fuel systems.

We do have water separators on our fuel tanks for our bulk fueling.
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
16,313
Re: Warning....Test your own gas

I still gotta dissagree with Dingbat AND silvertip.
maybe you folks just dont see many hulls that hold 100 plus gallons that tend to sit months at a time here in a relativly warm and very humid place.
here we are seeing E fuels do nasty stuff.
I said a jar of fuel would evaporate before it would collect enough water to seperate. Ever seen a 100 gallon jar. :D:D

The issue is very real. I carry 145 gallons of fuel onboard. I've was hit twice this season with water problems. I pumped 2 gallons of water/alcohol mixture out the first time and an additional 1/2 gallon out of the tank 6 weeks later. I use stabilizer and Startron religiously so don?t count on miracle juices keeping it from happening to you.

When the day time highs are in the upper 80 to 90 degree range everyday with evening lows in upper 70?s to low 80?s and a constant dew points above 70 degrees, it?s an issue.
 

eli_lilly

Chief Petty Officer
Joined
Dec 22, 2005
Messages
435
Re: Warning....Test your own gas

Bring your boats on down to South Florida during the summer rainy season and you'll find out whether ethanol phase separation really exists. I've had numerous portable 6 and 12 gallon tanks phase separate in one boat since it was introduced down here last November. I just had to pump out 40 gallons of phase-separated ethanol from the other boat. The additives like Stabil Marine and Startron only help to a small extent.

When the fuel phase-separates, what is left is a layer of alcohol & water sitting under a tank of super-low octane fuel. A Racor will pull the water out, but the fuel making it through the filter is too low-octane to start the outboard. You can start it on a portable with fresh fuel, but when you switch back to the tank the outboard will run horrible. Cars and lawnmowers will run OK on the fuel. It's like a nightmare.

-E
 

PeterMcG

Seaman
Joined
Nov 3, 2009
Messages
61
Re: Warning....Test your own gas

This is true.
When phase separation does occur, even if you remove the water/ethanol phase layer so that it is usable fuel, the octane rating on the remaining fuel will be lower.
(While ethanol provides less energy when it undergoes combustion, it has an octane rating of about 113, so it does provide a boost to the overall octane rating.) You could boost the octane rating back up by adding any of several different additives (MTBE, toluene, etc.).
 
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