How does ethanol in gas affect 356 engine/fuel system?

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Barry Brisco
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Re: How does ethanol in gas affect 356 engine/fuel system?

#16 Post by Barry Brisco »

Interesting article about the use of fuel stabilizers to reduce the likelihood of phase separation in E10 "gasohol", see

http://www.historicvehicle.org/Latest-N ... -Additives
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Jay Broemmel
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Re: How does ethanol in gas affect 356 engine/fuel system?

#17 Post by Jay Broemmel »

I've been using both those Eastwood products for a year. Glad to know they're actually doing something. Interesting how the effectiveness is doubled by mixing them

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tyler carlson
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Re: How does ethanol in gas affect 356 engine/fuel system?

#18 Post by tyler carlson »

I am glad to see this topic remain a permanent sticky. It is a valid point and appears it will only get worse as time passes. It all starts with the eco-people back in the early 70's and their 'get the lead out' cries. We all want to breath cleaner air-but we are here to talk about some effects the ethanol gas is having on our cars. Living here in the People's Republic of California we have been using ethanol for years without much fanfare-and there are probably more 356s in this state than anywhere else on the planet. The lead issue hasn't really been a problem for the 356 as we use hard valve seats and mostly run stainless valves. Reading some of the above/ongoing postings I can see possible performance problems being blamed on the lousy ethanol gas we are forced to use. The ethanol gas is designed to burn cleaner. It does this by making the engine run hotter-we are not talking much-maybe 20 degrees. Your engine runs best when it is fully warmed up and produces less hydro-carbons. Some of the previously mentioned problems could be related to ethanol fuels but sound like simple adjustment issues. Overheating can be linked to dragging brakes-improper valve adjustment and running the car too lean. Proper jetting is another issue directly linked to the way a car is driven-especially with ethanol fuels. There is a tendency to run cars too lean on many of the blog/topics-just my opinion! I run mine slightly richer-not to the point of fouling plugs-i use a 'tad' more gas-but who cares. The ethanol fuels are air/oxigenated but not to the point it looks like 7-up! A problem on older cars and on some 356/912 motors is vapor lock. It is rare though. Its cause is simple. Think of a bubble in a carpenter's level-the leveling bubble in the glass tube. As the gas or more correctly the gas line gets hot-the 'bubbles' in the line expand-filling up the line-almost like a blockage-very little fuel gets by. The line cools-the cars runs great again. The simple fix is to get the line off the tin that comes into the fuel pump. The heat coming off the head is 'wicked' by the fuel line laying on the horizontal tin. It looks terrible but sometimes insulating that line solves problems. Ethanol fuels tend to give the outward performance of 'lean'-hence running your motor slightly richer makes good sense-this will also cool your combustion chamber(we're not talking a whole lot here!) but it helps. Old racing addage-"go rich and advance" . There is another problem with ethanol fuels eating up vintage 'rubber' pieces within the entire fuel system-mostly fuel pump diaphrams-petcocks=true. Most of the replacement parts available to us these days have long ago been made from hi-tec neoprenes designed to take on these fuels. Its the N.O.S. parts stashes folks get into and think how great they are using a original part from the 1960's-that won't hold up to the 'corrosive' effect ethanol has on them. And probably the underlying cause of many engine fires-don't panic! There are specific gasoline brands that are to be avoided-probably true. Run the good stuff-stop shopping for cheap gas. Life is too short to drink cheap wine. Jetting....a personal thing 'driven' by the way the car is to be used. Standard jetting-ethanol fuels-seem to work fine for our daily drivers or cars being driven to occasional meets. Racing applications for ethanol fuels....not favorable-no comment! Additives may help-ones i tried were about as effective as the 'Flintsone vitamins" i took-they didn't work either. Ethanol fuels are here to stay-get use to it-make the simple adjustments.
 

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Re: How does ethanol in gas affect 356 engine/fuel system?

#19 Post by Mark Erbesfield »

I run a fleet of small equipment, we see two problems as noted above. Rubber and plastic degradation and water and trash attraction to the ethonal. Ethonal needs to stay blended and suspended in the gas so it will burn off. As it gets older it attracts moisture and sinks to the bottom of the tank causing more problems not to mention that the fuel goes bad fast. I will be attending a seminar soon that will be discussing these issues. I will report back with any positive info. We are considering on-site fueling stations with "Recreational" fuel, which has no ethonal. Essentially mid grade with no ethonal added. Cheaper too, but technically not allowed for street use.
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tyler carlson
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Re: How does ethanol in gas affect 356 engine/fuel system?

#20 Post by tyler carlson »

That is a good point Mark-"ethanol needs to stay blended and suspended in the gas so it will burn off". I had heard that before-several times and thought 'really...?' I blew it off as the ramblings of fellow jabber-talkies. But there must be something to it! I like the 'recreational fuel' thing too. I have friends that have loaded up their 356/911/912's on 100 octane fuel at small private airports-of course they were using it for 'recreation' also!
 

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Re: How does ethanol in gas affect 356 engine/fuel system?

#21 Post by David Jones »

Frank;
Try the 91 octane and if the engine knocks under load you cannot use it in that car. There is sometimes a fine line between knock and no knock on non ECU controlled cars. If you have an ECU then the knock sensor will back off the timing and change the injection to compensate. As most people never use all the horsepower available it is questionable if the drop in performance will even be noticed.
The most serious downside of using ethanol laced gasoline is the fact that it will deteriorate if exposed to ambient air, mostly as a result of moisture absorbance but it also has a deleterious effect on rubber and plastic components not suitable for use with ethanol. Older cars in particular are susceptible of course.

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Gas Options

#22 Post by Frank Meek »

Hi there
Here is another way to travel...
http://pure-gas.org/
Hope this helps.
Best regards,
Best regards,
FE Meek

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tom meighan
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stale fuel

#23 Post by tom meighan »

Hi all
As time goes by the interval between drives of my 65C become longer (I am the original owner and in my 80s). To avoid the stale gas situation I keep the fuel level somewhat above “Reserve”. When needed I add a couple of gallons of fresh fuel. This occurs about every 3 to 5 months. Is this approach good enough? I have an electric auxiliary pump to fill the bowls and the amount of cranking is not excessive (sometimes 2 or 3 attempts). Would a shot of Sta-Bil with the fresh fuel be prudent or a waste? Related question which might avoid an inconvenient trip to the gas station (does fresh fuel in a tightly closed full gas can remain fresh for months? -- thinking no evaporation). Thanks
Tom
 

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Re: stale fuel

#24 Post by Glenn Ring »

With today's E10 fuel. it can go stale in as little as a month. I've been told use use the "blue" fuel stabilizer if i'll not be using the car for more than a month or so.
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Barry Brisco
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Re: stale fuel

#25 Post by Barry Brisco »

Tom, if you read through the posts in the topic "How does ethanol in gas affect 356 engine/fuel system?" at http://porsche356registry.org/356talk/1/27108.html you will find quite a bit about using fuel stabilizers and how gas degrades over time. As Glenn points out, automobile gas degrades fairly rapidly, and it is an issue for our 356's.

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tom meighan
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Re: stale fuel

#26 Post by tom meighan »

Barry
Perhaps you could direct me to the part that discusses going stale in a completely full closed container where evaporation cannot take place.
Tom
 

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Re: stale fuel

#27 Post by Vic Skirmants »

Tom,
Evaporation is not the issue; it's the basic crap formulation of our current fuels.

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Re: stale fuel

#28 Post by tom meighan »

Hi Glen
Sta-Bil offers a Marine Formula product. Is this the one you meant?
Tom
 

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Frederick Adler
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Re: stale fuel

#29 Post by Frederick Adler »

Long carbon chains in 'gas' degrade with time. Its not evaporation. The alcohols are a "kick" that helps the overall ignitability. Alcohols volitalize at lower temps. PV=nRT. The stabilizers slow down the degradation. On my 914 which was seldom run the stabilizers from more reputable vendors worked but I never kept the tank with more than a quarter so when I got it started I could go down and top off with high test.

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Mike Acebo
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Re: stale fuel

#30 Post by Mike Acebo »

An answer to Tom's question from BP about fuel storage including 10% ethanol:
http://www.opalfuel.com.au/assets/conte ... ing_A3.pdf

Mike

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