Does mixed fuel age?
 

KLC Lewis wrote:
"That raises another question. Every year at winterizing time, Essie
gets some stabilizer of some type or another added to her diesel fuel.
This is the same fuel every year, as Essie just sips the stuff daintily
and would never even dream of guzzling. So the question is, does the
stabilizer evaporate or otherwise dissipate during the course of the
year, or does it "build up" in the fuel?"

The "stabilizer" stays in the fuel, but usually will never reach
concentrations that would do any harm. But there are other factors in
fuel that degrade over time so it is a good idea to replace fuel that is
more than two to three years old, according to a few engine 'experts'
I've read articles by, including those at Mack Boring - the importers
for Yanmar.

And this brings up another point. Several diesel engine 'experts' I've
read recommend never using the same biocide more than two seasons in a
row, due to the microbe's penchant for becoming *immune* to that
particular biocide. So it is recommended to change type of biocide
periodically. If using biocide, make sure you don't use too much, or
keep adding it over time to the same fuel - some brands will precipitate
hard abrasive solids out into the fuel if in too high concentrations,
which could clog filters or harm engines if passed by filters. We're
talking only capfuls here.
Please don't ask for cites, it'll take months of re-reading to find
them! :) I'm just going by the notes I took.

Red

Does mixed fuel age?
 

Hi,
in the back of my mind I seem to recall hearing that the mixed oil and
petrol fuel as is used in outboards "ages"

Can anyone advise as to whether this is correct?

cheers,
Peter

Does mixed fuel age?
 

On Tue, 03 Apr 2007 14:15:02 GMT, Charlie Morgan
wrote:

On Tue, 03 Apr 2007 09:47:55 -0400, Peter Hendra
wrote:

Hi,
in the back of my mind I seem to recall hearing that the mixed oil and
petrol fuel as is used in outboards "ages"

Can anyone advise as to whether this is correct?

cheers,
Peter

Yes, it does.

CWM
Charlie,
Are you able to give an idea of the time factor please

regards

Does mixed fuel age?
 

"Charlie Morgan" wrote in message
...
On Tue, 03 Apr 2007 12:33:28 -0400, Peter Hendra
wrote:

On Tue, 03 Apr 2007 14:15:02 GMT, Charlie Morgan
wrote:

On Tue, 03 Apr 2007 09:47:55 -0400, Peter Hendra
wrote:

Hi,
in the back of my mind I seem to recall hearing that the mixed oil and
petrol fuel as is used in outboards "ages"

Can anyone advise as to whether this is correct?

cheers,
Peter

Yes, it does.

CWM
Charlie,
Are you able to give an idea of the time factor please

regards

If you added a fuel stabilizer product such as "Stabil" when it was
freshly pumped and mixed, it should be usable for 3-4 months or so.

CWM

That raises another question. Every year at winterizing time, Essie gets
some stabilizer of some type or another added to her diesel fuel. This is
the same fuel every year, as Essie just sips the stuff daintily and would
never even dream of guzzling. So the question is, does the stabilizer
evaporate or otherwise dissipate during the course of the year, or does it
"build up" in the fuel?

Does mixed fuel age?
 

On 2007-04-03 12:33:28 -0400, Peter Hendra said:

On Tue, 03 Apr 2007 14:15:02 GMT, Charlie Morgan
wrote:

On Tue, 03 Apr 2007 09:47:55 -0400, Peter Hendra
wrote:

in the back of my mind I seem to recall hearing that the mixed oil and
petrol fuel as is used in outboards "ages"

Can anyone advise as to whether this is correct?

cheers,
Peter

Yes, it does.

CWM
Charlie,
Are you able to give an idea of the time factor please

History won't help us much in the US, because they're adding ethanol
and that's causing all sorts of problems.

My friends run their outboards dry in the fall, then add small amounts
of what's left over from the season to their cars' tanks. Don't do that
just before you go for an emissions test, of course, but they report no
problems.

--
Jere Lull
Tanzer 28 #4 out of Tolchester, MD
Xan's new pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI pages: http://homepage.mac.com/jerelull/BVI/

Does mixed fuel age?
 

"Jere Lull" wrote in message
news:2007040320000575249-jerelull@maccom...
History won't help us much in the US, because they're adding ethanol and
that's causing all sorts of problems.

My friends run their outboards dry in the fall, then add small amounts of
what's left over from the season to their cars' tanks. Don't do that just
before you go for an emissions test, of course, but they report no
problems.

--
Jere Lull
Tanzer 28 #4 out of Tolchester, MD
Xan's new pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI pages: http://homepage.mac.com/jerelull/BVI/


If I put 10% ethanol gas in my Highlander -- a fuel which costs exactly the
same as 100% gasoline of the same purported octane rating -- my mileage
drops from 21.5 per gallon to about 19.7. Virtually 10% lower mileage for
putting this non-fuel into my tank. This means that I have to burn more
"mixed fuel" (though about the same amount of actual gasoline) to travel the
same distance, but at 10% higher cost. I'll never understand why this is
supposed to be "good for the environment." Or, for that matter, for my
pocketbook. I have no idea what ethanol might be doing to my engine's hoses
and fittings, but being 2007 model, I hope that it's factored-in.
Nevertheless, I will only buy the 10% crap if I can't find any of the uncut
stuff.

As for the outboard's unused fuel, since the Suzuki outboard is
oil-injected, I don't have to pre-mix the gas and oil, so anything left in
the tank should go right into the Highlander with no problems at all. :-)

Karin

Does mixed fuel age?
 

On Tue, 03 Apr 2007 09:47:55 -0400, Peter Hendra
wrote:

Hi,
in the back of my mind I seem to recall hearing that the mixed oil and
petrol fuel as is used in outboards "ages"

Can anyone advise as to whether this is correct?

cheers,
Peter

Please forgive my insistence, but can anyone give me any idea how many
months I can keep mixed outboard fuel - petrol and oil.

It's great to know that yes, definitively, it does age but it would be
really helpful for a cruiser such as myself to know;

1. How long I can keep mixed fuel?

2. What happens when it is aged? - Does it become less useable in any
way such as clogging carburetors etc

Thanks
Peter

Does mixed fuel age?
 

Peter,
A good rule of thumb is untreated mixed gas will last about 2 months. After
that it "sours", fouls the plugs, doesn't burn right etc.
I have no idea of the chemical reason for this, I just know I've used this
rule since the USN taught me to mess about with rubber ducks 25 years ago
and it works for me.
MMC
"Peter Hendra" wrote in message
...
On Tue, 03 Apr 2007 09:47:55 -0400, Peter Hendra
wrote:

Hi,
in the back of my mind I seem to recall hearing that the mixed oil and
petrol fuel as is used in outboards "ages"

Can anyone advise as to whether this is correct?

cheers,
Peter

Please forgive my insistence, but can anyone give me any idea how many
months I can keep mixed outboard fuel - petrol and oil.

It's great to know that yes, definitively, it does age but it would be
really helpful for a cruiser such as myself to know;

1. How long I can keep mixed fuel?

2. What happens when it is aged? - Does it become less useable in any
way such as clogging carburetors etc

Thanks
Peter

Does mixed fuel age?
 

On Wed, 04 Apr 2007 04:58:22 -0400, Peter Hendra
wrote:

It's great to know that yes, definitively, it does age but it would be
really helpful for a cruiser such as myself to know;

1. How long I can keep mixed fuel?

2. What happens when it is aged? - Does it become less useable in any
way such as clogging carburetors etc

If you add stabilizer when fresh, it should be OK for at least 4
months, possibly more if stored in a cool place out of the sun.

As gasoline (petrol) ages it loses octane and tends to form varnish
deposits. Octane loss causes pre detonation and is harmful to
pistons, varnish deposits are harmful to the carburetor.

Does mixed fuel age?
 

"Charlie Morgan" wrote in message
...
On Tue, 3 Apr 2007 17:00:56 -0500, "KLC Lewis"
wrote:

That raises another question. Every year at winterizing time, Essie gets
some stabilizer of some type or another added to her diesel fuel. This is
the same fuel every year, as Essie just sips the stuff daintily and would
never even dream of guzzling. So the question is, does the stabilizer
evaporate or otherwise dissipate during the course of the year, or does it
"build up" in the fuel?


The fuel still deteriorates, just not as fast. If your diesel is more than
2
years old, I'd pump it out, clean the tank and put in some fresh stuff.

CWM

That was my assumption as well. Yet it still burns cleanly, no smoke, and
doesn't clog my filters. Asking my boatyard guys for advice, they pretty
much all agreed that as long as that was the case, there was little point in
changing it out.

Still, I think this year at launch I'll have the tank drained and start
anew. The diesel that's in there is at least six years old.