New Gasoline - Too many problems

dvasile · Jun 18, 2012

I just had my carburetor pulled and cleaned, also my choke was frozen on my 6hp yamaha 2 stroke. Seems to be running nice now.

davenlynn · Jun 18, 2012

Questions:

1. Do you use "Stabile" type additive in the tank?

2. Do you disconnect the fuel line at the end of the day and run your outboard dry??

Dave
S/V Trial and Error
San Diego

Ross S · Jun 18, 2012

Automotive fuel systems are sealed from the environment (i.e. not vented to atmosphere). Fuel injection runs under very high pressures compared to carbs and the fuel delivery is closely monitored by a host of sensors and the fuel injectors are adjusted accordingly. This can actually mask a whole host of engine problems.

Maine Sail · Jun 18, 2012

jibes138 said:
I keep seeing recurring issues in posts about outboard motors trying to run on new vintage gasoline I assume with E10. My question to the experts out there, why can I leave my car for an extended period and it starts right up with no problems at all, then runs fine, but these outboard motors gum up, need carburetors rebuilds, etc, etc? What is different about the outboards? OK they have carburetors instead of electronic fuel injection. Wouldn't the injectors gum up just as bad as carburetor jets? Wouldn't a large gas tank have the same problems with phase separation and water from condensation? Something is wrong with the design of these small motors IMHO. Any comments? I too have had troubles so just trying to better understand the problem.

Our old M3 sat over the winter, with Stabil, and still had MASSIVE fuel problems in the spring so bad I was forced to take it to the dealership and bend over.... My dad has a large collections of antique cars and he drives 13 hours to a "top secret" small airport in Pennsylvania, with his car hauling trailer filled with 5 gallon gas cans, to buy ethanol free fuel for storing the cars. Cars that are "long term" (not driven each year) he disassembles the carbs and literally blows out the fuel lines and fuel tanks so they are 100% empty.. My entire youth all my dad ever did was throw some Stabil in them and they ran every spring with zero issues. Now none of them do unless he buys the "smuggled in" gas or completely drains them... Even the ethanol free gas is still not as good as the old stuff for some reason but he claims much better and worth the 13 hour drive than e10...

Our Honda lawnmower is on its third carb!!!!:cussing:

Ross · Jun 18, 2012

My twenty year old lawnboy 2cycle is used and shoved into the shed all summer and after the last use in the fall is parked with what ever fuel is left in the tank. In the spring I take the cover off the air cleaner and give it a shop of starter fluid and it fires right up. I suspect that the problems are in the manufacture of the machine.

Mike B1026 · Jun 18, 2012

Sad to hear

Sorry to hear that. I've been using Stabil for years and switched over to Marine Stabil (more concentrated) when it came out. But I usually drain my fuel tank and carb if it's been sitting for long & then run the old gas though my truck (only 5 gallons or so)

Any one have experience with Star Tron?? I have heard a few good things but haven't really researched it.

Maine Sail said:
Our old M3 sat over the winter, with Stabil, and still had MASSIVE fuel problems in the spring so bad I was forced to take it to the dealership and bend over.... My dad has a large collections of antique cars and he drives 13 hours to a "top secret" small airport in Pennsylvania, with his car hauling trailer filled with 5 gallon gas cans, to buy ethanol free fuel for storing the cars. Cars that are "long term" (not driven each year) he disassembles the carbs and literally blows out the fuel lines and fuel tanks so they are 100% empty.. My entire youth all my dad ever did was throw some Stabil in them and they ran every spring with zero issues. Now none of them do unless he buys the "smuggled in" gas or completely drains them... Even the ethanol free gas is still not as good as the old stuff for some reason but he claims much better and worth the 13 hour drive than e10...

Our Honda lawnmower is on its third carb!!!!:cussing:

Mike B1026 · Jun 18, 2012

Old vs New

Your "old" mower doesn't meet the stricter EPA rules either. I suspect the tighter tolerances needed to meet lower emissions also are easier to clog. I also suspect the 2-cycle mixture might help to preserve the fuel better.

Ross said:
My twenty year old lawnboy 2cycle is used and shoved into the shed all summer and after the last use in the fall is parked with what ever fuel is left in the tank. In the spring I take the cover off the air cleaner and give it a shop of starter fluid and it fires right up. I suspect that the problems are in the manufacture of the machine.

Ross S · Jun 18, 2012

Newer 4 stroke motors are most prone to E10 fuel problems

Ross said:
My twenty year old lawnboy 2cycle is used and shoved into the shed all summer and after the last use in the fall is parked with what ever fuel is left in the tank. In the spring I take the cover off the air cleaner and give it a shop of starter fluid and it fires right up. I suspect that the problems are in the manufacture of the machine.

Lawn mowers, snow blowers and older small motors in general do not have to meet today's strict emission standards as today's new outboard motors have too. These emission standards force the use of smaller jets and leaner mixtures, both of which makes carbs more prone to any varnish or contamination.

2 stroke motors tend to have larger jets which also helps make them less prone to the carb gumming up. I don't know what, if any, effect the oil mixture has on the gas itself.

anchorclanker · Jun 18, 2012

Please remember, fuel is not the same all across the country, it varies by region, state, even by county. There are so many formulations and different chemicals used/not used, all in some twisted effort under the ruse its for out own benefit. The problems you are seeing or not seeing may not be relevant to someone two counties over or a state away.

Also, standard ethanol gasoline is supposed to be 10% max, and the Govt used to keep a good eye on it. The last several years has seen a surge of reports of wild amounts of alcohol in regular gasoline, far above 10%, some claim to have seen amounts over 50%. You can get away with it in a fuel injected car engine with an O2 sensor, the computer will alter the fuel mixture to compensate. A carburetor cannot do that because of its fixed jets. Pure Ethanol would require jets to be increased about 1.8 times to burn a 100% ethanol fuel mixture. If you got a high enough dose of alcohol it will go super lean, and can, will, and does burn up engines, usually by burning holes through the pistons. The primary ones most are seeing are outboards, jet skis, and snowmobiles, but it does do it to cars too. There are testers on the market now for under $10, that you can use to check ethanol percentage in the fuel. Cheap insurance.

davenlynn · Jun 18, 2012

I use nitro methane (CH3NO2) in my 5 hp four stroke and it pushes my Mac 25 at 47 kts. Just foolin' around. Actually there's not a damn thing we can do about fuel and no one in charge seems to care. So, in the long run we pay for it through extra maintainance and repairs.

caguy · Jun 18, 2012

davenlynn said:
I use nitro methane (CH3NO2) in my 5 hp four stroke and it pushes my Mac 25 at 47 kts. Just foolin' around. Actually there's not a damn thing we can do about fuel and no one in charge seems to care. So, in the long run we pay for it through extra maintainance and repairs.

Not true you can buy LL100AV fuel. There is no ethanol. The ethanol absorbs water that reacts with the aluminum in the bowl of the carb. It is that aluminum oxide that plugs up the idle jets. Not the jet that you can see when you look down the venturi but the one that is internal.
Things that you can do to help with regular ethanol gas is to keep your tank topped off to prevent water in the air from being absorbed into the gas. Another thing you can do is drain the carb after use. Don't use the carb drain but simply run the gas out of the carb by disconnecting your fuel and run the engine while flushing it out at the wash station. Its amazing how long it takes to run the fuel out.
Anyway thats my 2 cents worth.

seadaddler · Jun 19, 2012

WoW

Thank you guys for the info and helping us having less out board problems for sure.
I buy enthonal free gas where I can find it here florida or lots of Marina's now sell enthonal free gas and have not had any problems doing so but think I will still take the carb off and clean out all the jets with tiny wire once a year.
Nick

hewebb · Jun 19, 2012

If possible go to a small airport and get 100LL AV fuel and those problems will go away. For diesel use jet fuel. Several around here do this for storing over winter. Some of us use jet fuel in our diesel engines that do not get used much. i.e in and out of the slip area.

anchorclanker · Jun 19, 2012

100LL AV fuel is leaded fuel. LL stands for low lead, not unleaded. Aircraft need the lead to operate at high altitude. Makes no difference to me what ya burn, just making sure y'all know its leaded fuel.

While Ethanol does react with aluminum, once again, certain locals around the country use chemicals that form all kinds of nasty crystalline deposits. Consider yourself lucky if your not seeing them or have had to deal with them. I've seen carbs completely encrusted with greenish yellow crystals in less than 6 months of non-use. The float gets stuck, frozen, the jets (all, main included) and passageways clogged, its nasty stuff. Yet just getting out of town, out to another county and the fuel is better. In fact some of its so bad your cars get as much as 50% worse mileage on that garbage.

Jet fuel in a diesel? Just be careful you get Jet A and not Jet B (JP-4). Jet A has the same basic flash point of diesel, JP-4 is similar to gasoline.

Running the engine out of fuel, rather than simply draining the carb bowl, really is the best way. Although I would still drain the bowl after it quits if you want to be really protective. Running it out clears all the passageways of fuel, nothing left to eat or decay or form anything nasty. But there will still be a small amount lingering in the bowl you want to get out of there. I would follow up with a few shots of fogging oil, or try to do it simultaneously just before it quits.

Many are many calling for fuel to have a national formula, and we should all support it. It will save us a lot of $$ at the pump by allowing the refineries to process one kind of fuel, and having it all one formula will put us all on a level playing field. It may be sucky fuel, but if were all dealing with the same stuff we can probably figure out how to deal with it.

tsheie · Jun 19, 2012

I don't think it was mentioned yet in this thread, but another factor to consider is the fuel pump-- ethanol was the culprit in my Merc outboard, making the rubber diaphragm plates in the fuel pump brittle, instead of flexible, so it missed-sputtered-coughed all the time.. once the fuel pump was overhauled (fairly simple), I now only buy non-oxygenated premium fuel, add a can of SeaFoam to it, and it runs like a charm.. I do the same with the fuel for the Nissan9.8 on our sailboat...

rgranger · Jun 19, 2012

Ross S said:
Automotive fuel systems are sealed from the environment (i.e. not vented to atmosphere). ...

One thing that is sure to help is to remember to close the fuel vent when you are not using the outboard. If you let the can "breath" you will accumulate moisture in your tank over time and you will allow for the evaporation of the more volatile components of your fuel. Gasoline is mostly 5 to 10 carbon long hydrocarbon chains along with some aromatic compounds but ... there are trace amounts of larger stuff dissolved in the gas. So if you let the gas evaporate over time, the larger "gummy" stuff gets concentrated as the lighter hydrocarbons evaporate. (That is why it is a good idea to disconnect the fuel line and run your carburetor dry). So old fuel is not necessarily bad if you topped off the tank and kept it closed up tight. This is what Ross was saying about the automotive system.

rgranger · Jun 19, 2012

Jibes

I think it is just a matter of degree... Have you ever left your gas can for the lawn mower out in the sun? I have. And it expanded a lot. And I have a can in my shed that is half crushed due to the contraction that it underwent during the night when it cooled back off. I suspect that those of us who leave their gas cans for their O.B. in the cockpit have more trouble with this sort of thing than those who have fixed cans below deck. Just because it is exposed to the sun on a hot day.

There could be more to it... but that is my gut feeling on this.

Indysailor · Jun 19, 2012

We had a similar discussion going on here:
http://forums.s2.sailboatowners.com/showthread.php?t=135138

This report was linked in that thread:
http://www.tradeonlytoday.com/home/516866-report-shows-e15-damage-in-marine-engines
I think there is a click through to get to the article.