93 Octane? / boaters targeted?

Kracken

Petty Officer 2nd Class
Joined
Jul 17, 2009
Messages
158
I was flipping through my Volvo-Penta 5.0Gi owner?s manual and I read this:

?Use gasoline with an octane number of at least 93 (RON)
Fuel Injected engines can run on gasoline down to 90 Octane (RON) if 93 octane fuel is not available but some power will be lost. Return to 93 octane as soon as possible?

This can't be accurate. Most marinas carry 89 octane, at least in New Hampshire.


It also clearly stated all Volvo-Pentas cannot operate on anything higher than E10. The feds are trying to up the ethanol to 15%. If this happens we are all screwed. :eek:
 

jriegle04

Petty Officer 2nd Class
Joined
Jun 1, 2009
Messages
179
Re: 93 Octane? / boaters targeted?

i see more ethanol related threads everyday. the marinas seem to be making a lot of money off of the problems created by ethanol. i would bet they will be selling it very soon from their dock pumps.....
 

Kracken

Petty Officer 2nd Class
Joined
Jul 17, 2009
Messages
158
Re: 93 Octane? / boaters targeted?

OK, so

Regular (87) octane is 90 (RON)

Plus (89) would be 93 (RON)

Sweet I can live with that.
 

dkorzun21

Chief Petty Officer
Joined
Mar 22, 2009
Messages
427
Re: 93 Octane? / boaters targeted?

This has me thinking im a new boat owner with a 1989 larson all american carbed . What should I run in this I usally put 87 in it :confused:
 

Numlaar

Chief Petty Officer
Joined
Jul 9, 2009
Messages
633
Re: 93 Octane? / boaters targeted?

I always get a kick out of concern over octane rating...

I took some advanced fuel classes when I worked for Amoco, and as an ASE master tech...

All "octane" is, is a spark inhibitor... Basically it prevents fuel from igniting solely due to compression. The reason you see it recommended for "high performance" engines, is because they typically run at a higher compression ratio than regular engines.

In effect, if the octane is too low, you get "knocking" which is caused by the fuel igniting from compression before the spark actually sets it off (think diesel, that doesn't use spark plugs at all).

I have always been taught to go with the lowest octane you can, without getting engine noise... anything more than that is just a waste. (I really laugh when I see people putting "104 octane boost" in cars, thinking they'll go faster :D ). In fact, lower octane fuel starts and burns easier because of the lower octane rating!

There is absolutely no difference in the fuel itself, other than the amount of inhibitor installed in it to get the higher "octane" rating.

Hope ya'll find the information useful :)
 

dwentz

Recruit
Joined
Jun 23, 2009
Messages
2
Re: 93 Octane? / boaters targeted?

I do agree on the Octane, but in many cases the fuel is different. You can see the difference, Regular is usually more red to yellow in color. I use Premium, in all my small engine equipment and in my boat, and here is why.

Try this for your self it is an easy test, just not very fast. This test can be run on multiple brands of gas, I tested 3 stations in my area that I usually use.

Each station takes 2 baby food jars for each class of fuel. I tested all 3 standard grades.

Fill 2 jars with each grade. You need a place for the jars that it outside protected from the weather, and someplace that the open fumes will not ignite, or cause a problem.

1 Jar put the lid on, the other leave the lid off.

The closed jars you will watch to see how the fuel separates. I ran my test over 2 years on these jars.

The open jars you allow to evaporate, hence they are outside, and not in the house or garage. Observe what is left in the jars as the fuel has evaporated. What I have found in every case is that the premium fuel leaves very little or no trace of gunk in the bottom of the jar. The lower grade fuel usually leaves a gum and or a shellac like residue in the open jar.

If you want to see something interesting add some Stabil to the test set in another 2 jars that are left open. In one of the jars add a steal washer. The jars with the Stabil in them will be the worse of the bunch, the one with the steal washer will form a crystal type crud around the washer.

The closed jars we actually did a test on the combustibility of the fuel at 3, 6 12, and 24 months and the premium also did better in all cases. Stored in a air tight container with out any additives it was still usable after 2 years. These tests are beyond the ability of the typical person to preform. We built a combustion chamber that measured the force of the fuel as it was fired after being shot into the chamber by a fuel injector.

These test were done to determine the usability of fuel that was stored for use in a generator, but as a result of my tests I now only run Premium in anything that sits for any length of time, like my lawn equipment, generators, and my boat. I still run regular gas in my cars.

These are not specifically scientific tests, but made a believer out of me. I can say that I have not had a fuel related problem in any of my things other than water in the fuel, and that was due to leaving the mower out side.

I have been told that the premium grade fuels are refined an extra step to remove more impurities, and that is why they are a different color. I figure if I spend a little more for the fuel on these things I will save it in money and time not having to deal with carburetor problems, and such.

Dale
 
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