What fuel you runnin in 2 stroke ?

TonyL · Post by **TonyL** » Wed Jun 10, 2009 7:39 am

Hey guys, per another post , now I have the question. I have a 95 Merc.200 XRI (EFI),When I told my Mechanic (1 year ago)I was usin Chevron mid grade , his comment was that premium would be better.Been payin for the top stuff ever since.

$$$$$$$$
On another post the comment was made,that 87 was better , due to it burns faster than 92,better for 2 stroke , and this person advised ta check your owners manual.Now I'm scratchin my head , being an auto tech ,I have experienced driveability problems in the past with SOME vehicles that were usin 92 instead of just 87 , and it was due to the above mentioned reason.Usin 87 was better for these systems.I checked my 95 owners manual , states 87 octane minimum , also that a MID GRADE WITH FUEL INJECTION CLEANING ADDITIVES WOULD BE BETTER.The way it (I) reads , is that MID is recommended for the additives only,which leaves me wonderin , since I routinely use the Merc.additives , could I get away with just 87 ?I know you guys with OPTIs may have a different requirement stated in your owners manual , but mine states 87.Kinda like ta hear if anyone out there has been runnin 87 in an EFI for years with no problems.Thanks in advance !

Ranger Jason · Post by **Ranger Jason** » Wed Jun 10, 2009 7:47 am

I was told by a Mercury mechanic I respect very much that there is very little, if any, benefit from high octane fuel. He went on to say 87 is the least hydroscope of the 3 readily available grades and advised me to stick with it.

npangler · Post by **npangler** » Wed Jun 10, 2009 8:04 am

I have no idea if this is true or not but I have been told the higher octane fuels have more alchohol or methanol and that it breaks down the oil you put in the gas.

drew · Post by **drew** » Wed Jun 10, 2009 8:05 am

I would use mid grade or premium. Detonation would be my biggest concern. Higher octane fuels are more stable. The octane rating does not effect the burn rate or BTU/lb unless the fuel is highly adulterated with other compounds.

basspunisher24/7 · Post by **basspunisher24/7** » Wed Jun 10, 2009 8:17 am

I asked my merc mechanic about this issue and he said 87 is what I should be running. I have a 98 merc 200 efi and add additives regularly. I have not had any problems with using 87 octane! hope this helps, Chris.

WishinIwerFishin · Post by **WishinIwerFishin** » Wed Jun 10, 2009 8:20 am

I have always been told 87 in two strokes, so thats what I've always used.

cib11b · Post by **cib11b** » Wed Jun 10, 2009 8:40 am

Everyone thinks hey better gas better performance? Wrong! If your motor does not recomend it do not use it! Same with an everyday automobile. Use 87 my friend, You will same more money with the same performance.

TonyL · Post by **TonyL** » Wed Jun 10, 2009 8:43 am

Thanks for all the input guys , I'm makin the switch !!

I'll prolly save a couple of bucks before the summer prices hit !!

Shoot we'll be payin more for 87 than we pay for premium now !!!!!!

drew · Post by **drew** » Wed Jun 10, 2009 9:53 am

Marine engines in general work very hard. A marine engine is constantly loaded, they do not coast like a road vehicle. If you run your outboard hard, I recommend you stay with a higher octane fuel especially if you have not had any problems in the past.

The outboard manufactures octane recommendation is usually the minimum requirement. I have dedicated 20+ years of my life to IC engine design and manufacturing. A higher octane fuel is more stable because it is more consistent in its composition. Its has a lower amount of free radicals that will ignite prematurely at a lower pressure. The result of a low octane fuel in a highly loaded engine can cause pre-ignition and pre-detonation. Which is the number one cause for a reduced service life of hard working two strokes.

If your really concerned about your fuel choice contact Mercury and talk to one of their engineers. Although keep in mind that Mercury makes money from the sales and service of their product. Engineered obsolescences is a fact with all manufactured goods.

Bigbassmike · Post by **Bigbassmike** » Wed Jun 10, 2009 10:05 am

I have a 1984 Ranger 372v with a 150 hp black Max fuel injected engine. I have been running premium gas because that is what they recommended when I bought the boat. I did have to have the engine rebuilt in 1989 because I sucked up a ring and had a bad piston but I have not had any problems since then and it is still on the water eevry month after 26 years I have owned it. I would stick to what your engine Manufacturer recommends or just use the premium becuase it runs better and has fewer problems.

cib11b · Post by **cib11b** » Wed Jun 10, 2009 2:17 pm

drew wrote: The outboard manufactures octane recommendation is usually the minimum requirement. I have dedicated 20+ years of my life to IC engine design and manufacturing. A higher octane fuel is more stable because it is more consistent in its composition. Its has a lower amount of free radicals that will ignite prematurely at a lower pressure. The result of a low octane fuel in a highly loaded engine can cause pre-ignition and pre-detonation. Which is the number one cause for a reduced service life of hard working two strokes.

The fuel does burn better yes, But that does not mean it is the right fuel for the engin. A higher octane can cause things such as *ping* and other harmful things to your engine components if it is not ment for that high of an octane. Check with Mercury on this. You are going to get to many mixed answers.

rich mendoza · Post by **rich mendoza** » Wed Jun 10, 2009 3:07 pm

tonyl,

run the 87 and if your worried about it just run a can of BG 44k threw it every once and a while to clean it up!

TonyL · Post by **TonyL** » Wed Jun 10, 2009 3:11 pm

rich mendoza wrote:tonyl,

run the 87 and if your worried about it just run a can of BG 44k threw it every once and a while to clean it up!

Hey Rich , how you know about 44k !?!

TonyL · Post by **TonyL** » Wed Jun 10, 2009 3:20 pm

Was just curious , cause the BG guys say it's dealer stuff only , can't buy it over counter etc.

fishinman · Post by **fishinman** » Wed Jun 10, 2009 3:27 pm

been runnin 87 in my 150efi since I purchased itin 1998. no additives. no troubles. I once a year use this merc cleaner that looks like white foam coming out by following the on water or test tank directions made by mercury.

Alex M. · Post by **Alex M.** » Wed Jun 10, 2009 3:46 pm

I have '94 200EFI and only run 87. Never had a problem with it. The higher octane just means that there are more fuel additives to burn off=more gunk and crap that can damage/inhibit your outboard motor. I learned this from a Merc factory certified tech who I trust and have been using for years.

I do add fuel injection cleaner periodically, but that's about it.

BTW...
Those EFIs are freakin' bullet-proof!

rich mendoza · Post by **rich mendoza** » Wed Jun 10, 2009 3:50 pm

i work for the nor cal distributer.

drew · Post by **drew** » Wed Jun 10, 2009 5:27 pm

The statements below are just not true. The fuel burns the same at the same rate. It is just less prone to pre-ignition.

There is no extra additives in higher octane fuel that will gunk up your engine. The fuel molecules are of a more stable geometry. The lower octane fuels have fragmented pieces of hydrocarbons that are less stable. Its just a better quality fuel.

cib11b wrote: The fuel does burn better yes, But that does not mean it is the right fuel for the engin. A higher octane can cause things such as *ping* and other harmful things to your engine components if it is not ment for that high of an octane.

Alex M. wrote: The higher octane just means that there are more fuel additives to burn off=more gunk and crap that can damage/inhibit your outboard motor.

BTW...
Those EFIs are freakin' bullet-proof!

bustout · Post by **bustout** » Thu Jun 11, 2009 8:52 am

I used to run 89 in my 1985 200efi and switch to 87 when we had the really high gas prices last year.

I noticed that my injectors get clogged more frequently hence needing to use the "ring free" additive more. The additive is very expensive so I probably was spending the same or more using 87

I went back to 89 and no issues since

201Pro · Post by **201Pro** » Thu Jun 11, 2009 9:09 am

TonyL wrote:Hey guys, per another post , now I have the question. I have a 95 Merc.200 XRI (EFI),When I told my Mechanic (1 year ago)I was usin Chevron mid grade , his comment was that premium would be better.Been payin for the top stuff ever since. $$$$$$$$
On another post the comment was made,that 87 was better , due to it burns faster than 92,better for 2 stroke , and this person advised ta check your owners manual.Now I'm scratchin my head , being an auto tech ,I have experienced driveability problems in the past with SOME vehicles that were usin 92 instead of just 87 , and it was due to the above mentioned reason.Usin 87 was better for these systems.I checked my 95 owners manual , states 87 octane minimum , also that a MID GRADE WITH FUEL INJECTION CLEANING ADDITIVES WOULD BE BETTER.The way it (I) reads , is that MID is recommended for the additives only,which leaves me wonderin , since I routinely use the Merc.additives , could I get away with just 87 ?I know you guys with OPTIs may have a different requirement stated in your owners manual , but mine states 87.Kinda like ta hear if anyone out there has been runnin 87 in an EFI for years with no problems.Thanks in advance !

This subject has been beat to death in the past ... as for me, I've talked to both the factory tech and some independent mechanics. I've come away more confused than before ... in the past, I would put in premium in my EFI ... but was told by the factory that 87 would be fine ... other mechanics I've talked to say that these are "high performance engines" and should use premium ... I've read that the 'premium' fuel burns at a slower rate ...

Anyway, now, I'm using 89 or "mid-grade" in my ETECH ... occasionally, I put in premium. I do notice improved performance/throttle response when using premium. But for the most part, I use 89 90% of the time.

acm95301 · Post by **acm95301** » Thu Jun 11, 2009 9:59 am

I use 87 and frequently use Stabil fuel additive. When I used stabil on my lowly 25hp may top speed went from 28 to 40mph. I was suprised. my 13 gallon tank lasts me 2-3 trips to mcclure unless im trolling.

TonyL · Post by **TonyL** » Thu Jun 11, 2009 10:35 am

rich mendoza wrote:i work for the nor cal distributer.

Ahh , Awesome stuff ! I wasn't a believer of ANY "snake"oils , Till BG
came into our dealership , gave the techs samples for personal vehicles , I am a believer now !

mark poulson · Post by **mark poulson** » Thu Jun 11, 2009 10:38 am

Does using the BG additive void any warrantees?

TonyL · Post by **TonyL** » Thu Jun 11, 2009 10:57 am

201Pro wrote:
TonyL wrote:Hey guys, per another post , now I have the question. I have a 95 Merc.200 XRI (EFI),When I told my Mechanic (1 year ago)I was usin Chevron mid grade , his comment was that premium would be better.Been payin for the top stuff ever since. $$$$$$$$
On another post the comment was made,that 87 was better , due to it burns faster than 92,better for 2 stroke , and this person advised ta check your owners manual.Now I'm scratchin my head , being an auto tech ,I have experienced driveability problems in the past with SOME vehicles that were usin 92 instead of just 87 , and it was due to the above mentioned reason.Usin 87 was better for these systems.I checked my 95 owners manual , states 87 octane minimum , also that a MID GRADE WITH FUEL INJECTION CLEANING ADDITIVES WOULD BE BETTER.The way it (I) reads , is that MID is recommended for the additives only,which leaves me wonderin , since I routinely use the Merc.additives , could I get away with just 87 ?I know you guys with OPTIs may have a different requirement stated in your owners manual , but mine states 87.Kinda like ta hear if anyone out there has been runnin 87 in an EFI for years with no problems.Thanks in advance !
This subject has been beat to death in the past ... as for me, I've talked to both the factory tech and some independent mechanics. I've come away more confused than before ... in the past, I would put in premium in my EFI ... but was told by the factory that 87 would be fine ... other mechanics I've talked to say that these are "high performance engines" and should use premium ... I've read that the 'premium' fuel burns at a slower rate ...

Anyway, now, I'm using 89 or "mid-grade" in my ETECH ... occasionally, I put in premium. I do notice improved performance/throttle response when using premium. But for the most part, I use 89 90% of the time.

Yeahh , I figured this subject has been beat , but prolly will always reappear when gas prices climb.I'm considering switching to 89 , using additive every couple of tank fulls , but really wondering about 87 and doing the same , just wanted ta hear if anyone can attribute an engine failure to using the lower grade ,( not counting those who might be using plain cheap gas , I use Chevron).I'm tryin ta save a couple of bucks , but not willing to gamble a motor on it.

Terry · Post by **Terry** » Thu Jun 11, 2009 12:42 pm

TonyL,

I have the exact same motor you do and I have run both 87 and 89, with little difference, but I do run Chevron or 76. I was told the cheap fuels are murder on 2 strokes.

The motor is a beast, but it can't pass a gas pump without stopping. LOL

So far, as long as I run Merc oil and additives, and keep it carbon free, it hasn't failed since new. Knock on wood of course.

Terry

TonyL · Post by **TonyL** » Thu Jun 11, 2009 2:35 pm

Terry wrote:TonyL,

I have the exact same motor you do and I have run both 87 and 89, with little difference, but I do run Chevron or 76. I was told the cheap fuels are murder on 2 strokes.

The motor is a beast, but it can't pass a gas pump without stopping. LOL

So far, as long as I run Merc oil and additives, and keep it carbon free, it hasn't failed since new. Knock on wood of course.

Terry

Terry ,and others , thanks for the replies , yeahh ,I'll be knockin on wood also , gonna try mid for a while , then maybe 87 , keeping up on the additives of course. As far as the motor yup-likes gas , for the heck of it I just installed a fule flow meter , wanna try and get an idea if theres a sweet spot,where this beast uses the least amount of gas when runnin,I'm sure there'll be none-idle to wot-
likes gas !

blkdog812 · Post by **blkdog812** » Thu Jun 11, 2009 5:16 pm

on your motor, mid grade is the best. too many of the wrong additives in premium. and not enough in the 87. never any fuel related problems for me when running the mid grade on the older motors.
keep adding the sea form / carbon free or quik clean also.

TonyL · Post by **TonyL** » Thu Jun 11, 2009 5:40 pm

Cool!

Whoopbass · Post by **Whoopbass** » Thu Jun 11, 2009 9:22 pm

[quote="acm95301"]I use 87 and frequently use Stabil fuel additive. When I used stabil on my lowly 25hp may top speed went from 28 to 40mph. I was suprised. my 13 gallon tank lasts me 2-3 trips to mcclure unless im trolling.

C'mon.......Do you expect us to believe a fuel additive designed to preserve fuel gave you a 12 mph top end increase?

acm95301 · Post by **acm95301** » Thu Jun 11, 2009 10:03 pm

It did, initially I thought that perhaps the fuel I had been using was old thus the 28mph......but since using Stabil my average minium speed without it is still 32....and with it 40mph.

I'm a paramedic that fishes once a week, I'm not a pro or even that great a fisherman...I dont make money off any product ...so yeah I expect you to believe that in fact while using stabil I've had a massive increace in speed. As to the why it works....ask a mechanic.

Jeff Jewell · Post by **Jeff Jewell** » Fri Jun 12, 2009 4:58 am

Terry wrote:TonyL,

I have the exact same motor you do and I have run both 87 and 89, with little difference, but I do run Chevron or 76. I was told the cheap fuels are murder on 2 strokes.
Terry

All the gas is the same, all the refineries use the Kinder Morgan Pipeline. The gas makeup is mandated by the California Air Resources Board (CARB) yes the same great minds who gave us MTBE.. Some additives if any are added at the terminal. The one thing Chevron does do great is marketing........

Whoopbass · Post by **Whoopbass** » Fri Jun 12, 2009 5:42 am

[quote="acm95301"]It did, initially I thought that perhaps the fuel I had been using was old thus the 28mph......but since using Stabil my average minimum speed without it is still 32....and with it 40mph.

I'm a paramedic that fishes once a week, I'm not a pro or even that great a fisherman...I don't make money off any product ...so yeah I expect you to believe that in fact while using stabil I've had a massive increase in speed. As to the why it works....ask a mechanic.]

What boat/motor are you running?
I have a 15' Gregor with a 30 hp and can only get 28 mph.

I doubt that Stabil does anything. Maybe you had a partially plugged high speed jet and it cleaned it out. Try running without Stabil and see if there's a difference.

acm95301 · Post by **acm95301** » Fri Jun 12, 2009 8:43 am

I use a 25hp bass tracker pro team 165, 16' long.

The minium speed without the stabil hasn't gone all the way back to 28, so some "fuel cleaning" thing may have happened, but i get 32 without stabil...and 40 with.

TonyL · Post by **TonyL** » Fri Jun 12, 2009 10:50 am

Jeff Jewell wrote:
Terry wrote:TonyL,

I have the exact same motor you do and I have run both 87 and 89, with little difference, but I do run Chevron or 76. I was told the cheap fuels are murder on 2 strokes.
Terry
All the gas is the same, all the refineries use the Kinder Morgan Pipeline. The gas makeup is mandated by the California Air Resources Board (CARB) yes the same great minds who gave us MTBE.. Some additives if any are added at the terminal. The one thing Chevron does do great is marketing........

Then why is it that when I gas my 95 GMC 5.0l truck at chevron/arco-no problems , but the minute , and I mean minutes after gassing a usa ,or valero my truck pings (detonates)like a sonofa@#$%^ ! ?- The better stations add "additives"at the stations , in fact the truckers themselves do it,right as theyre droppin the gas load.Theres a little more than just marketing.

Jeff Jewell · Post by **Jeff Jewell** » Fri Jun 12, 2009 11:44 am

As I said the additives if any are added at the terminal...All the refineries use the same pipeline, and cover for each other when thier supplies run low because of turnaround and other unexpected maintenance.

big_limits · Post by **big_limits** » Fri Jun 12, 2009 11:57 am

Isn't the amount of ethanol the biggest factor?

1. It is dangerous to use greater than 10 % ethanol in marine engines.
Some gas supplies are illegally much higher. Check gas with an alcohol fuel test kit to make sure ethanol present is less than 10%.
A recent post on a Long Island, NY message board states,
"Believe it or not, some of the fuel samples tested 48 % ethanol and most were above the 10 % 'maximum allowable by law'.".
All marine engines sold in the United States are designed to operate on fuel containing no more than 10 percent ethanol. Engines built before ethanol became popular for environmental reasons, (past 10 years) have minimal safeguards from the damage alcohol fuels will cause.
2. Ethanol absorbs water - Water molecules combine with petroleum (gas) in your gas fuel tank and lines...
Ethanol has an increased risk of fuel water-contamination due to ability to absorb H20.
(Ethanol attracts and absorbs moisture from the air). Vapor lock and fuel starvation can occur.
The gasoline you pump in your tank may be dry, but due to condensation (from humidity, temperature, etc.) water does exist in your tank. Since water is insoluble in gasoline, it sinks to the bottom of your tank -
As long as it remains below the level of your fuel pickup tube it will not affect your engine. The problem is water is soluble in ethanol and will travel thru your engine fuel system.
A water/ethanol mixture, being heavier than gas, will sink to the bottom of the gas tank, leaving a lower octane gas on top. This low octane gas (lean fuel) can cause performance issues with 4-stroke engines, and can cause damage to 2-stroke engines.
Excess water in engines will also cause premature rusting.
3. Ethanol is an amazing solvent and cleansing agent
High levels of ethanol can dissolve, deteriorate and breakdown solid material, including rubber, plastic, fiberglass and even aluminum and steel.
Ethanol will also cleanse and release corrosive matter (gunk), varnish and rust, which will travel through the engine and clog fuel filters, carburetor jets and injectors. In many outboard engines it will also contaminate the fuel present in your fuel tank.
Ethanol tends to dissolve certain resins, which can travel through the engine intake and coat intake valves, causing sticking and bent pushrods or worse. This has been well documented for boats equipped with certain fiberglass gas tanks, made before the early 1990's.
The more gunk (rust, sediment, dirt, etc.) collected in your outboard engine over the years, the more noticeable the cleansing effects of alcohol will be noticed.
Ethanol's solvent and cleansing abilities can lead to engine failure and expensive (avoidable) repairs.
4. Ethanol can wear-down and dry-out the plastic and rubber parts in your engine.
Rubber seals and plastic material used in older boats are often not compatible with alcohol. Ethanol will make engine parts dry and brittle. Since ethanol is a cleansing and drying solution, it will clean the oil right off the internal components of a 2 stroke, Extra lubrication is necessary.
5. Ethanol blends can cause additional contamination by reacting chemically with MTBE fuel blends.
Do not mix gas that contains MTBE with ethanol E10.
Mixing MTBE fuel with ethanol blend fuel can create a gel-like substance that clogs passages in carburetors.
Stalled engines and engine damage are the result. Fuel injected engines have shown less damage, than carbureted engines, from this gel-like substance.
6. Engines with older fiberglass gas tanks have the greatest risks when using fuel with ethanol.
Fiberglass gas tanks can "deteriorate" from ethanol, causing this degraded resin stuff, (you'll see "black sludge") to circulate through your engine, coating intake manifolds and building up on intake valves - which basically destroys your engine.

Jeff Jewell · Post by **Jeff Jewell** » Fri Jun 12, 2009 12:29 pm

The last time I looked all Carb Spec gasoline was 5.7 % ethanol. However several ethanol plants have closed in the midwest due to the downturn in the economy and fuel demands. I doubt if there will be enough production of ethanol in the near future, to have 10% in California gasoline. Some of the best and brightest in the industry have proven we can make clean fuels without ethanol but politicians want us to use it....

DeltaDan · Post by **DeltaDan** » Fri Jun 12, 2009 5:43 pm

Jeff Jewell wrote:The last time I looked all Carb Spec gasoline was 5.7 % ethanol. ............... Some of the best and brightest in the industry have proven we can make clean fuels without ethanol but politicians want us to use it....

Spot On Brother !!

Terry · Post by **Terry** » Sat Jun 13, 2009 5:36 pm

Jeff J,

My boat's in Havasu, should've said that. Is the fuel there from the same refinery? Not being a smartarse, just wondering. So all gas is the same at the terminal in CA? Do additives like Chevron's "Techroline" (whatever that is) give any advantage or does it hurt?

Inquiring minds want to know.

Terry

Jeff Jewell · Post by **Jeff Jewell** » Sun Jun 14, 2009 7:54 am

Terry,
California has it's own blend of gasoline as mandated by the California Air Resources Board, it's different than everywhere else, that;s one reason our gas prices are usually higher than the rest of the continental US.
Arizona has what's called conventional gasoline, and they get gas from both California's refineries and the ones in the Texas Gulf Area's. They do have what's called Arizona RBOB â€“ Reformulated Blendstock for Oxygenate Blending, with ethanol as the oxygenate for use in the state of Arizona, but I don't know what the percentage is.......and weather it's just a summertime fuel or not...sorry

Tags

Notice