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David Gore
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Username: david_gore

Post Number: 1244
Registered: 4-2003
Posted on Wednesday, 13 March, 2013 - 08:41 am:   Edit PostDelete PostView Post/Check IP

Uh oh - looks like another robust discussion coming up so I have moved the relevant posts to this new thread. The following posts first appeared in the following thread:

http://au.rrforums.net/forum/messages/17/13497.html?1363129552

The point about octane rating not reflecting the energy content of fuel is correct of course. The point I was making and supported by Bill is the uncontested fact that the total energy content of ethanol blend fuel will always be less than that of straight petroleum fuel which contains more complex organic hydrocarbons than the basic C2H5OH structure of ethanol. Ethanol does have a high octane rating and regular E10 blend fuel does have a higher octane rating than straight regular fuel with the downside of lower energy content which results in higher fuel consumption [up to 10% in some cases] and increased running costs due to the Australian price of E10 being higher than it should be if energy content was the determining price factor.

The problems with E10 fuel for pre-1990 vehicles and for marine use are well-known and undisputed on this side of the world. The cars do not "die by the millions" but require expensive repairs to their fuel systems if the owners cannot afford or do not wish to replace their vehicle. The E10 has a purgative effect in the fuel tank as a consequence of the ethanol acting as a detergent to break up crud deposits which then clog the fuel lines/filter[s] and carburettor/fuel injection system. In almost all cases, the gaskets and seals used in cars of this era ARE NOT compatible with E10 fuel and have to be replaced if E10 fuel has to be used. The SU systems have experienced enough problems for Burlen to include conversion kits for ethanol blend fuels in their spare parts range. Water pick-up from the atmosphere by ethanol blend fuels has been a problem and its use for marine fuel is not recommended for this reason due to the safety risks involved with off-shore breakdowns. My local fuel supplier applied for and received an exemption from the legislated requirement that E10 fuel had to be stocked on the grounds a significant proportion of his sales were to boat owners who could not use this fuel. He also does not carry bio-diesel for this reason.

Of course, the actual ethanol content in the fuel is also relevant, whilst we have E10 [10% ethanol by volume]; other countries may have lower contents which may be less aggressive than the higher ethanol blends and less problems have been experienced as a consequence.
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Brian Vogel
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Username: guyslp

Post Number: 282
Registered: 6-2009
Posted on Wednesday, 13 March, 2013 - 04:23 am:   Edit PostDelete PostView Post/Check IP

Well, I'll be the contrarian regarding E10.

It's been the only commonly available fuel available in the U.S. in several decades and was incredibly common before then.

No upgrades were done on any of the gaskets, etc., in relation to either the fuel pumps or carbs and both cars have run just fine for years and years on E10. One of the two was a London delivery car and one was U.S. delivery car.

Brian
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Jeff Young
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Username: jeyjey

Post Number: 124
Registered: 10-2010
Posted on Wednesday, 13 March, 2013 - 05:04 am:   Edit PostDelete PostView Post/Check IP

OK, then I'll be contrarian regarding octane. ;)

Octane is not a measure of the energy content of the fuel; it's only a measure of its predisposition to self-ignite under compression.

A higher octane fuel allows a higher compression ratio, and a higher compression ratio will get more of the energy out as useful motive power. But for a given engine at a given compression ratio, a higher octane fuel (above what is necessary to prevent pre-ignition) won't help any.

Cheers,
Jeff.
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Brian Vogel
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Username: guyslp

Post Number: 283
Registered: 6-2009
Posted on Wednesday, 13 March, 2013 - 06:31 am:   Edit PostDelete PostView Post/Check IP

Jeff,

That's not being contrarian, that's being accurate.

My anecdotal observations about cars not spontaneously dying by the millions that were built before E10 became the predominant fuel are borne out by a number of studies:

Effects of Intermediate Ethanol Blends on Legacy Vehicles and Small Non-Road Engines, Report 1 - Updated, 2009

Issues Associated with the Use of Higher Ethanol Blends, 2002

Changes in Gasoline IV: The Auto Technician's Guide to Spark Ignition Engine Fuel Quality, 2009

These publications get into really gory detail about virtually any aspect of fuel for gasoline or gasoline-blend powered road vehicles you can think of.

Brian
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Brian Vogel
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Username: guyslp

Post Number: 285
Registered: 6-2009
Posted on Wednesday, 13 March, 2013 - 09:07 am:   Edit PostDelete PostView Post/Check IP

David,

I will simply say that I want hard data, studies, that bear out all of the anecdotal statements about E10 being aggressive on fuel system components. I have tried, tried, tried and simply cannot find them. This isn't my first time "at the dance" and the only evidence I've ever been provided with is limited to anecdotal and where any number of other factors could have been at play beside ethanol in fuel.

Virtually all of the hard data on marine use being problematic was linked directly to the sealants used in marine tanks for decades and that ethanol does dissolve same and pull it through the system. Marine fuel in many, if not most, locations in the U.S. is still pure petroleum. That is changing, though.

It has long been my belief that most of the so-called ethanol-resistant component marketing is just that: marketing. I have nothing to support that other than my observations about what's not happened to cars all around me that were unaltered over the years.

The United States has had E10 for years now. There are not now and have not ever been any massive efforts to change fuel system components here. Fuel systems are not being eaten alive by E10, unless one believes there's a massive and successful conspiracy to prevent any information about same to be distributed. Being a thrifty sort (read: I've never owned a brand new car) I drove several pre-1995 model year cars well into the E10 era here that I know never had fuel system component replacements (other than filters) and that ran regularly for years without them. Currently, my oldest car is a 1996 model year (that's excluding the cars from Crewe previously mentioned).

This will be my last post on this topic (at least in this iteration) because it's one of the "opinion chasms" of the automotive world. People need to read what's out there, pay attention to what they've observed around them, and make an informed decision regarding whether they feel preemptive action is needed on changing out fuel system components based upon same. I make no secret that my opinion is that, as a general rule, E10 is a non-issue for automotive use with no changes to the cars at all.

Brian
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David Gore
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Username: david_gore

Post Number: 1246
Registered: 4-2003
Posted on Wednesday, 13 March, 2013 - 09:34 am:   Edit PostDelete PostView Post/Check IP

Hi Brian,

Please keep contributing on this topic, you are entitled to hold and express your opinions freely and openly on this forum.

Some useful references:

http://www.racq.com.au/motoring/cars/car_advice/car_fact_sheets/ethanol

http://www.productionautomotive.com.au/blog/e10-fuel-the-info-you-need-to-know.html

http://www.bia.org.au/TradeEvent/Ken-Evans.pdf

The last paper based on the boating industry by a Mercury representative is the most detailed and lists almost all the problems experienced here in both automotive and marine applications.
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Brian Vogel
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Username: guyslp

Post Number: 287
Registered: 6-2009
Posted on Wednesday, 13 March, 2013 - 11:13 am:   Edit PostDelete PostView Post/Check IP

David,

First, and you clearly understand that based on the tone of your response, absolutely none of this "is personal" other than the opinions I've formed based on the data I have examined.

I find it interesting that the Mercury document (the third in your list) presents incorrect information regarding the likelihood of phase separation in ethanol-blended fuels. This Memo from the U.S. EPA goes into phase separation in detail. (Yes, it's old, but the science hasn't changed, either.) All indications are that ethanol-blended fuels are less subject to phase separation than conventional under most conditions. As one of the RROC-US members pointed out the last time this was brought up there, "Free water and phase separated ethanol are NOT the same thing. Alcohols have been used for generations as 'gas tank driers'; they remove minor amounts of water from the system." I'll also note that said commenter is a chemical engineer with years of experience in the field. The document also has a focus on concentrations greater than E10 while making it appear that E10 is what's being discussed in a number of places. In addition, I don't know where they came about forming the opinion that MTBE and ethanol don't mix. Until the recent phase out of MTBE here in the states the two were used together for years without the effects they describe.

The "E10 Fuel Info You Need to Know" starts out with an inaccurate description of octane and what it means (quoted material in blue):

The higher the number the better for your vehicle
The first big myth. Anything that's at or above the octane necessary to prevent engine knock is all that's necessary.

–this is because the higher the octane reading, the lower and more controlled the burn of the fuel is.
This is true, essentially.

This gives you more power for each combustion stroke within the engine and, the slower the burn, the less amount of fuel you will utilise.
I don't think I need to go into the errors here. They're blatant, particularly linking burn rate (as described by octane, as opposed to energy contained in a specific volume of fuel [yes, E10 definitely does have less energy content per gallon than pure petrol]) to fuel consumption.

I do think it's interesting that the RACQ fact sheet notes 1986 as their "cut off" date for E10 likely being fine for a car in its original form. That's about the earliest date I've ever seen published.

Brian
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David Gore
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Username: david_gore

Post Number: 1247
Registered: 4-2003
Posted on Wednesday, 13 March, 2013 - 03:24 pm:   Edit PostDelete PostView Post/Check IP

Brian,

I included those references purely for evaluation and initiation of discussion purposes. The Mercury paper was presented to a Boating Industry Association Conference with the Company's approval; I think it reasonable to assume the information was vetted and approved by their technical personnel prior to presentation. The RACQ paper specifically excludes carburettor vehicles from their 1986 transition date and subsequent amendments to the list of vehicles compatible with E10 have occurred on a regular basis as experience was gained by our various State motoring organisations through their Road Service and Technical Advisory assistance to members with problems.

I must point out my advice re the problems with using E10 fuel in unmodified SU fuel systems applied to a 1972 Shadow - this is a known problem and one which requires attention if E10 will be used in this vehicle. The Australian Ethanol blend compatibility guide provides the following information:

Bentley: all Australian models since 1990 are suitable for E5 and E10 blends.

Rolls-Royce: all Australian models since 1990 to 2002 are suitable for E5 and E10 blends [as BMW models from 1986 are listed as being compatible, it may be assumed the post-2002 R-R engines are compatible].

http://www.fcai.com.au/environment/can-my-vehicle-operate-on-ethanol-blend-petrol

Note: a significant number of vehicles sold here well into the 1990's and some extending into the 2000's are listed as being incompatible with E5/E10. The US situation for equivalent models sold in this market may be different due to different design rules/emission standards being applied.
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Brian Vogel
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Username: guyslp

Post Number: 288
Registered: 6-2009
Posted on Thursday, 14 March, 2013 - 12:39 am:   Edit PostDelete PostView Post/Check IP

David,

This comment is not specific to the articles you posted, but a general "warning," when it comes to ethanol there is a great deal of misinformation out there, much of it promulgated by various trade groups. There are numerous errors in the Mercury paper and often these sorts of presentations are made to address (and sometimes feed) preconceived notions.

One of my favorite additional articles to throw out in these conversations is one written after a study sponsored by Hagerty Insurance (a big classic car insurer here in the USA, I don't know if they operate elsewhere): Ethanol: Demonic or Divine?. There is also a tiny follow-up blurb posted in February 2013, but I'm still trying to find the study itself, as I like to see the gory details.

I guess, in the end, I'm back to my original position: read what's out there, talk to other owners of the car(s) your concerned about that have transitioned from E0 to E10 to see what they did or did not have to do, then make your decision.

As a general rule I have found the "collector car community" to be an incredibly efficient generator of urban legends on a number of subjects. My first reaction is no longer panic (which it once was - I presumed an expertise that I've now found is not there) but "get thee to the library!!" (or the electronic equivalent thereof and pay careful attention to the evidence presented by any material you find and the methods employed to get same).

We had panics here in the U.S. about unleaded gas being the end of collector car engines and E5 and E10 being the end of collector car engines/fuel systems and neither has been borne out. There are all sorts of precautionary "watch for"s, but that's just what they are - things to be watched for, not presumed as occurring of necessity. This was equally true for more "modern" cars that were declared as on their way to the junkyard because they were supposedly incompatible with E10. It simply didn't happen and that's with no preemptive action. I suppose this could be different in different markets, but fuel line and seal standards have been in place for so long that I can't imagine there are many, if any, market specific seals or flex lines for automotive use.

We shall have to agree to disagree without being disagreeable. It appears we're both quite capable of doing so.

Brian
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David Gore
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Username: david_gore

Post Number: 1248
Registered: 4-2003
Posted on Thursday, 14 March, 2013 - 08:50 am:   Edit PostDelete PostView Post/Check IP

Hi Brian,

The situation here appears different to the US experience quoted by you - perhaps we have a car fleet with a greater average age and owners who keep their cars on the road instead of junking them when a major problem occurs.

My reservations on ethanol blend fuels for older cars is based on personal experience with 3 pre-1990 family cars that experienced fuel system problems after the use of ethanol blended fuel. Later model cars with fuel systems compatible with ethanol blends is entirely another matter; I am strongly against the ability of vested interests to achieve a selling price for E10 where the discount is significantly less than that required to make E10 an economic replacement for petroleum-based fuel based on the increased comparative fuel consumption of vehicles using E10. The diversion of food crops to ethanol production is also a concern for me when this results in increased food prices from total demand being greater than supply and ethanol producers can outbid food processors/resellers for the available produce. I am a strong supporter of the use of biomass technology for fuel production especially where waste organic matter can be used as feedstock.

I have not and will not discuss the use of "pseudo-science" by both sides in discussions about ethanol blended fuel. This is one area where consensus is unlikely to be achieved due to emotional rather than rational factors dominating the discussion. The application of the scientific method and having an open mind is often foreign to some contributors in these discussions.

I am not disagreeing with you, I am just presenting an alternative point of view based on actual experience and observations in both automotive and marine applications following the introduction of ethanol blended fuel in Australia. Whether I am in the majority or the minority remains a personal judgement for others. As a former professional applied scientist, I will always listen to alternative points of view and respect those that hold these points of view. I have also changed my opinions as a consequence of rational and logical comments by others that have created doubt in my mind about my opinions.

The world would be a much less interesting place if we had to be a "mutual admiration" society and a much less enjoyable place if "win-lose" outcomes had to prevail. I try to create an environment where the middle ground between these extremes prevails. The only circumstances where I will become disagreeable is when abuse, denigration, vilification or libellous behaviour arises and I have to take corrective action.
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Brian Vogel
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Username: guyslp

Post Number: 290
Registered: 6-2009
Posted on Thursday, 14 March, 2013 - 01:52 pm:   Edit PostDelete PostView Post/Check IP

David,

I don't know how to respond since I haven't been viciously attacked!! I'd like to resort to abuse and denigration, but I can't stand being insincere! ;-)

I absolutely cannot and will not contest that individual experiences do vary, and one's suggestions to others are (and should be) colored by one's own personal history.

Just FYI, here is another document from 2011 from the Renewable Fuels Association, Gasoline Ethanol Blends and the Classic Auto. While it may not apply to circumstances in Oz, if we have any Canadians or citizens of the USA reading it may.

I've also written directly to one of the principle researchers of the Hagerty-funded study to see if it's been published anywhere that can easily be accessed. I'll post any information I get back here if/when I get it.

Brian
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Geoff Wootton
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Username: dounraey

Post Number: 122
Registered: 5-2012
Posted on Thursday, 14 March, 2013 - 02:24 pm:   Edit PostDelete PostView Post/Check IP

I generally shy away from these potentially divisive discussions, as I hold both Brian and David in the highest regard and would not wish to offend either. However after reading the horror story that is the Mercury document I have decided to add my own, anecdotal story to this thread.

About 8 months ago I stripped both carburetors completely to clean them out and to check the condition of the rubber diaphragms, which are prone to causing fuel leakages. I have to report that both carburetors were as clean as a whistle and the rubber diaphragms were in perfect order, neither hardened nor cracked. I normally take detailed photos during any procedure I carry out on the car, not least because it's the only way I can get the damn thing back together again. Unfortunately I forgot to take photos of the float chambers, but do have one of the main jet, which I reproduce here:

main jet

This photo was taken before any cleaning, as evidenced by the petrol spillage.

I don't discount the information given in the Mercury document, quite the contrary. However, there are so many references to fibreglass fuel tanks that I wonder if this is the source of the black goo that covers the carburetor internals, inlet manifold and valves.

Possible reasons for such clean carburetors on my car could be:

Car was used very infrequently by the previous owner.

The very low humidity here in Vegas (16%) - maybe part of the problem is high humidity as would be experienced in marine engines.

That the carburetors had been recently overhauled by the previous owner. I doubt this to be the case however, given that this car had been previously poorly maintained.

I intend to take a pragmatic approach on this issue, "keeping an eye" on the fuel lines and components. One of the really good upshots of this discussion for me has been that I have finally gone out and bought a fire extinguisher, something I should have done months ago but never quite got round to doing.
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Peter Talbot
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Username: squerryes

Post Number: 186
Registered: 7-2010
Posted on Thursday, 14 March, 2013 - 08:01 pm:   Edit PostDelete PostView Post/Check IP

Below is an extract from an email received today from careline@bp.com :

Thank you for your email concerning the fuel sold by BP.

In most regions of the UK our Ultimate Unleaded dos not contain any Ethanol at present (South West UK excluded). This may of course change in the future as the specification allows up to 5%.

Our Regular grade gasoline does contain up to 5% bio ethanol in compliance with EN228 gasoline specification allowance in most regions of the UK.

It would seem that we don't have a problem in much of the UK - YET!!

Peter
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Peter Talbot
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Username: squerryes

Post Number: 187
Registered: 7-2010
Posted on Thursday, 14 March, 2013 - 08:14 pm:   Edit PostDelete PostView Post/Check IP

I found the below article of interest:

http://www.groups.tr-register.co.uk/wessex/ethanol-update.html

Peter
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Brian Vogel
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Username: guyslp

Post Number: 291
Registered: 6-2009
Posted on Thursday, 14 March, 2013 - 11:44 pm:   Edit PostDelete PostView Post/Check IP

Peter,

There are numerous errors of fact (some that I've seen again and again) in that article, but I'm going to limit myself to a single one:

"Ethanol has a higher volatility than petrol and therefore is vaporises more readily."

This simply isn't the case. There are definitely more issues today with vapor lock than there were in the past, but that's even with pure petrol. Gasoline of today, pre-ethanol, is nothing like it was even 10 years ago, and much of that has to do with tweaking in formulations, even those that make petrol more or less volatile based upon the season.

There was a long thread entitled Fuels on the RROC-US forums (you'll only be able to click through if you're a member of the RROC-US and logged in) that is nauseatingly detailed on this. It was written by Gary Phipps. It's too much effort to try to reproduce the whole thing here, but I'll snag the first post to show why the whole "ethanol is the culprit in vapor lock" argument in the USA falls apart very quickly. Quoted material by Gary in blue:

The question occasionally arises as to whether premium grade as opposed to regular petrol would be better/worse/no different from the standpoint of preventing vapor lock. In my continuing research I came upon a very interesting EPA document giving detailed information about US petrol over the years 1995-2005. A document with that data for later years would be helpful but apparently no such update has yet occurred. Even this 2005 data was not published until 2008.

The two attached images should tell the story.
RVP = vapor pressure at 100F, more is worse for causing vapor lock
RFG = reformulated gasoline, the stuff of CA and other 'non-attainment' areas
CG = conventional gasoline

The RFG data shows a rule change in 2000 but otherwise its the same information as the (non-graphical) data for CG: there is no useful difference in the RVP of premium vs. regular. The small difference, in 0.1's if a psi, varies from year to year but which one has less RVP is not something you can predict. There is no mid-grade CG data since it is rarely a different fuel; its almost always a mixture of regular and premium at roughly a 1:1 ratio.

Note the big difference in Summer/Winter RVP in the CG table. 8.2 vs 12. That is why you do NOT want to be using winter petrol in the summertime. Fuel grade makes no difference; the season makes a big difference.


RVP in U.S. Gas 1995-2005

Conventional Gas (E0) Vapor Pressure}

There continue to be more and more complaints about vapor lock here in the USA. This even while RVP has been going down as a general rule to prevent vapor emissions.

Brian
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Peter Talbot
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Username: squerryes

Post Number: 188
Registered: 7-2010
Posted on Friday, 15 March, 2013 - 03:22 am:   Edit PostDelete PostView Post/Check IP

Brian

Our interpretation as to the value of published Articles obviously differs and is futile to expand further.

Peter
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Brian Vogel
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Username: guyslp

Post Number: 292
Registered: 6-2009
Posted on Friday, 15 March, 2013 - 04:15 am:   Edit PostDelete PostView Post/Check IP

Peter,

OK. But since ethanol has a boiling point of 173F at sea level, and any number of the hydrocarbons in gasoline boil well below that, it's impossible to accurately state that ethanol is more volatile than petrol. Any article that states this is suspect from the get-go.

I shan't bother with any of the other issues in that article as I agree that it's an exercise in futility.

Brian
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Randy Roberson
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Username: wascator

Post Number: 101
Registered: 5-2009
Posted on Saturday, 16 March, 2013 - 01:38 am:   Edit PostDelete PostView Post/Check IP

Vapor pressure of motor fuel is adjusted seasonally in the US, I am told. Here in the South, we have alternating days/times of cold and warmish weather in winter, as well as in the seasonal transitions, and if one had a tank of "winter" formulation and the ambient temp rose, plus add in city stop-and-go, etc., could this not encourage vapor lock?
Also I imagine but am not certain that RVP "up North" may be even higher in winter than here in the South, for obvious reasons.
Poor old ethanol may be taking the blame for a lot of other ills, although personally I am no fan of it. I think it's a creature of politics much more than of engineering, and I try to avoid it for my old cars.
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Brian Vogel
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Username: guyslp

Post Number: 295
Registered: 6-2009
Posted on Saturday, 16 March, 2013 - 02:31 am:   Edit PostDelete PostView Post/Check IP

Randy,

Yes, using winter formulated fuel (which isn't limited to the USA, it's pretty standard practice to tweak fuel based upon anticipated delivery date and expected "use through" period) can certainly contribute to vapor lock if you're running it in warmer weather. That's precisely the point that Gary was trying to make in his closing line in the material I quoted.

I'm quite agnostic as far as ethanol use goes, but the fact is that it's here to stay if only as an oxygenating agent. If it is necessary to "tweak" one's classic car to fit the fuel, that's the thing that will be required. Like all mass produced goods fuel is going to be constantly "tweaked" to meet the needs of today, whenever today is. Collector cars aren't even an afterthought in the tweaking equation and never will be.

Brian, who believes in:
a) picking one's battles
b) knowing when "resistance is futile, you will become one with the borg"
c) getting as much hard data as possible to determine what "becoming one with the borg" actually entails
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Vladimir Ivanovich Kirillov
Experienced User
Username: soviet

Post Number: 24
Registered: 2-2013
Posted on Saturday, 16 March, 2013 - 06:05 am:   Edit PostDelete PostView Post/Check IP

Amazing scientific facts have been posted here about E10. My experience of the ethanol blended fuel is that on earlier cars, ie cars that don't run computerized fuel injection is that E10 is totally poisonous and there is no way I would have it in the Camargue. Had a 1990 Falcon panelvan, simple carburated engine. All of a sudden it ran like a hairy goat and my boss asked me if I was using E10 in it, and when finding out I was he told me to switch back to normal fuel and that he had made a fortune out of doing repairs to engines stuffed by E10. Put the car back on normal fuel and its run 6 years plus without missing a beat. But that's just my experience with it.
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Jan Forrest
Grand Master
Username: got_one

Post Number: 462
Registered: 1-2008
Posted on Saturday, 16 March, 2013 - 09:29 pm:   Edit PostDelete PostView Post/Check IP

Much the same arguments have been made about the use of dewatered and filtered waste (used) vegetable oil in older diesel engines. This quite neatly avoids the awkward fact that Rudolph Diesel designed his compression engine to run on veg oil from the outset. This does not apply to many of the newer 'common rail' or direct injection engines as they can be damaged by high %ages of veg oil in the fuel mix although they are mostly happy to run on true biodiesel.

At least in this case there are a couple problems which can arise. If the oil hasn't been fully dewatered or had all the solids filtered out to comfortably below 5 microns then it can soon block a modern fuel filter. Many people who filter oil tend to warm the oil first so it runs through faster and seems more efficient, but this tends to liquify some of the lighter fats which may then settle out if the temperatures drop significantly. Similarly it is alleged to have a scouring action in the fuel tank and feed lines with the same consequences. Also if you swap back & forth between veg and biodiesel the first less then perfectly converted oil can easily gell in the fuel lines blocking them badly enough to require complete replacement.

I've ran several cars on veg over the last few years and only had the most minor problems with it. In every case it's been tracked down to old fuel filters which were long past their use-by-date and were already way overdue for replacement. Fortunately I always carry a spare filter in the back of the car along with a few tools for such exigencies.
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Vladimir Ivanovich Kirillov
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Username: soviet

Post Number: 26
Registered: 2-2013
Posted on Sunday, 17 March, 2013 - 12:32 am:   Edit PostDelete PostView Post/Check IP

An interesting point about common rail diesels is the extreme danger of the high pressures they run. I did the Euro 4 course in Sydney when I worked for a large bus company there. We were shown a photo of a man's arm who had opened the injector line on a common rail diesel while the engine was running (a big no no)and his arm looked worse than what an arm looks like after its been shot with 12 guage buckshot from a shotgun wound. All the flesh was blown off from around the main bone. These systems operate at 30,000 psi and up. I can see big lawsuits on the way as the stickers the manufacturers use to warn of the danger melt off and fade overtime. Out here in outback Australia hardly anybody knows of the dangers of common rail injector lines but they soon will as more farm hands get their arms, faces etc blown to smithereens. Apart from that commonrail is a much more efficient system than non commonrail but they use electronic control systems (computers) to run and these are fine until they give problems and they have to be transported long distances to be diagnosed by some repair shop that has all the diagnostic computers to work out what is wrong with them and that in itself is often not the easiest thing to do even when you have the right gear.
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David Gore
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Username: david_gore

Post Number: 1250
Registered: 4-2003
Posted on Sunday, 17 March, 2013 - 07:54 am:   Edit PostDelete PostView Post/Check IP

The main problem with the various forms of bio-diesel is for engines that have been certified for compliance with the current European exhaust gas standards for particulate matter. To comply with these standards, the engines have to be fitted with particulate filters [DPF] and the different combustion characteristics of bio-diesel to mineral diesel means the filters are more likely to clog up with carbon particulates and require more frequent regeneration [thus reducing the service life] than filters on engines fueled with mineral diesel.

Another important factor is the engines MUST use low-ash synthetic oil [at a corresponding cost penalty] as the ash cannot be removed by regeneration and will eventually permanently clog the filter reducing its effectiveness and subsequent replacement at considerable cost [currently several thousand AUD].
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Fearne
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Posted From: 86.165.61.97
Posted on Tuesday, 19 March, 2013 - 10:47 pm:   Edit PostDelete PostView Post/Check IP

This is my hands-on experience with the 5% Ethanol being added to petrol in the UK. In GXO71 (1929 20/25) the fuel tap started leaking after using Ethanol. Stripping it down revealed a moth eaten gasket - probably years old.

I replaced it with a new gasket, sourced from Fiennes. For those who do not know, Fiennes is probably the most respected 20/25 engineering and spares vendor in the UK.

After fitting the new cork gasket, all was well for 6 months or so and then the tap started leaking. I tightened the nut, one position on the castellated nut/split pin. All was well for another few months and then it started to leak again.

This time I stripped the tap down and found that the new gasket had degraded. I got on to Fiennes, who stated that they had similar stories flooding in and that the cause was Ethanol. It eats cork. They were still researching for an alternative material, but meanwhile are supplying their customers with new cork gaskets, together with a small tube of some special gunk. This is smeared both sides of the Cork and is designed to hold the Ethanol at bay.

When the tap begins to leak again, it is my intention to make a new gasket from 4mm Teflon and give that a go.

(Message approved by david_gore)
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Peter Talbot
Prolific User
Username: squerryes

Post Number: 189
Registered: 7-2010
Posted on Wednesday, 20 March, 2013 - 09:46 am:   Edit PostDelete PostView Post/Check IP

Ethanol eats cork ?? Can this really be true ??

Cork has been used for decades to cap botles of fine wines (with an ethanol content of 11-12 percent) and fortified wines (with an ethanol content of 18-27 percent)without problem. There is,however,a significant difference in the type of cork used to cap bottles and that used for gaskets - for fine and fortified wine the cork employed is "ex tree" as stripped from the cork oak (an evergreen Mediterranean tree whose porous bark yields cork) whilst the cork used for gaskets is an artificial composite of cork granules held together by a combination of adhesive, heat, and pressure.

So - I would query the statement "Ethanol eats cork" and suggest that consideration be given as to the ethanol resistance of the adhesive employed to produce cork copmosite for gaskets.

Peter
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Patrick Francis
Prolific User
Username: jackpot

Post Number: 125
Registered: 11-2016
Posted on Sunday, 21 May, 2017 - 05:00 am:   Edit PostDelete PostView Post/Check IP

Hi All
I was not sure which thread to post this on, so this seemed the most relevant one.

I was talking to a friend of mine at a Classic Club Rally today who informed me that he was having a problems getting his Bentley to idle smoothly. It would work fine as soon as he depressed the accelerator though.

After some research he found an article that I include below. Appaerntly, modern fuels have a different specific gravity to old fuels, and so factory float level settings sometimes give a slightly high float level which causes richness and slight rough running on idle only - which disappears as soon as the throttle is depressed.

He now adjusts his float level by looking down the jet tube with the dashpots removed and his fuel pumps working.

It worked for him!! I hope this helps someone get that "extra smooth idle" that has flummoxed them over the years!

It should be pointed out that the constant depression S.U carb is NOT dependant upon exact fuel level heights but fuel should be visible down the jet orifice when the dashpots are removed. However it is important that the fuel level is not too high, which does occur when the float levers are set to workshop manual settings. Modern fuels demand that the levers are set lower, and any amount of flooding by having fuel level high in the jet, is to be avoided.
Float needle valve bodies cannot be changed on S.U carbs without distorting the valve body unless the correct extra slim S.U box spanner is used. This special but cheap spanner is available from Burlen.


Happy fiddling!!
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Patrick Francis
Prolific User
Username: jackpot

Post Number: 133
Registered: 11-2016
Posted on Wednesday, 24 May, 2017 - 08:54 pm:   Edit PostDelete PostView Post/Check IP

I will be checking the jet tubes in the Shadow and Mark2 out in the near future, and will let you all know what I find......
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Patrick Francis
Prolific User
Username: jackpot

Post Number: 135
Registered: 11-2016
Posted on Monday, 29 May, 2017 - 04:03 am:   Edit PostDelete PostView Post/Check IP

OK guys
Since I am waiting for a couple of spares for the Rolls, I had a look at the Jag Mk2 which also has SU carbs.
Looking at the SU website, they say that by the book, the level of the fuel should be 3/8" (0.8mm) below the jet bridge.
That means that if you remove the pots and positons on the carbs and look into the hole where the jet needle goes down, you should see the fuel level 0.8mm below the flat "bridge" that you can see.
BUT SU say that the fuel level is not critical and measuring the float height by fitting a 11mm drillbit between the float forks and the face of the float lid is sufficient to obtain an acceptable fuel level in the float chamber.

So, my Mk2 has two SU carbs, on an XK 3.8 engine that, by design, sits slightly aft down in the engine bay.
To make things worse, the left hand carb has the float chamber on the left of the carb, and the right hand carb has the float to the right of the carb.

I removed the pots, and switched the ignition on (therefore fuel pumps) so that the float heights reached their designed level, and noticed that the rhs fuel level was in fact about 0.8mm below the bridge, but the LHS fuel level was a lot lower, probably 2.5mm below the bridge.This is due to the carb - float layout mentioned earlier.

Neither of the two were OVER the bridge which is what I was expecting after reading my previous entry.

I then adjusted the float heights to get the 0.8mm below bridge on both carbs, and put everything back together.

The car seems to idle a bit smoother, but I cannot be sure.

My conclusion is that the fuel levels seem to be an inexact science (within limits) - most of the smoothness of the running being more dependant on the air and mixture screws.

In fact float levels change relative to the incline that the car is on.

I may change my mind when I check the Rolls!

Another interesting thing is that the idle adjustment on the Jag is regulated purely witgh the air mixture screws - not the throttle stop screw. Whereas the Rolls' idling is adjusted with the throttle stop.
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 1372
Registered: 9-2004
Posted on Monday, 29 May, 2017 - 04:17 am:   Edit PostDelete PostView Post/Check IP

Patrick F, did you do a CO check before and after?
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Patrick Francis
Prolific User
Username: jackpot

Post Number: 137
Registered: 11-2016
Posted on Monday, 29 May, 2017 - 05:26 am:   Edit PostDelete PostView Post/Check IP

Patrick, unfortunately no. I do not have a CO meter. I know I should have done...
I have a friend that has one and is going to lend it when we coincide....
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Jonas TRACHSEL
Prolific User
Username: jonas_trachsel

Post Number: 134
Registered: 2-2005
Posted on Monday, 29 May, 2017 - 03:16 pm:   Edit PostDelete PostView Post/Check IP

Patrick
You write: the level of the fuel should be 3/8" (0.8mm) below the jet bridge
3/8" translates to 9.5mm. On the other hand 0.8 mm is 1/32". What is the correct fuel level actually?
Jonas
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Patrick Francis
Prolific User
Username: jackpot

Post Number: 138
Registered: 11-2016
Posted on Monday, 29 May, 2017 - 04:57 pm:   Edit PostDelete PostView Post/Check IP

Hi Jonas, sorry about that - stubby fingers on my calculator I think. Here is the text from the SU website:

Float chamber fuel level

The fuel level on an S.U. is not critical, and need not be treated with meticulous accuracy-the normal level is 3/8 in. under the rectangular inner facing known as the jet bridge, but this is rather difficult to observe even with the suction chamber and piston removed and the jet fully dropped. However, a simple mechanical check can be made, and this consists of sliding a certain diameter of check rod between the lid face and the inside curve of the forked end of the hinged lever when the needle valve is in the 'shut off' position. The size of this rod for both the 1 7/8 in outside diameter smaller float chamber and the larger one of 2 1/8 in outside diameter is 7/16 in. On the HS type of float chamber a 5/16 in. rod is used with a brass float, and a 1/8 in. rod when the hinged nylon float is fitted. If the hinged lever fails to conform within 1/32 in. of these check figures it must be carefully bent at the start of the fork section, in the necessary direction for correction, taking care to keep both prongs of the fork level with each other. It must be emphasized that it is not advisable to alter the fuel level unless there is trouble with flooding; and although a too high level can cause slow flooding, particularly when a car is left ticking over on a steep drive, it should be remembered that flooding can also be caused by grit in the fuel jamming open the needle valve, or undue friction in the float gear, or excessive engine vibration, or a porous float.
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Patrick Francis
Prolific User
Username: jackpot

Post Number: 139
Registered: 11-2016
Posted on Monday, 29 May, 2017 - 05:13 pm:   Edit PostDelete PostView Post/Check IP

http://sucarb.co.uk/technical-su-carburetters

This is the site page. I think I used .8mm as a guide making my fuel levels too high.
Will check later and revert!
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Patrick Francis
Prolific User
Username: jackpot

Post Number: 145
Registered: 11-2016
Posted on Monday, 12 June, 2017 - 01:25 am:   Edit PostDelete PostView Post/Check IP

OK guys.
Just to give this issue with float heights some closure.
After playing around a bit, my opinion is that the float heights are not that critical in the SUs - so long as:
1. They are within the ballpark by using the 11.1mm drill bit to adjust the fork height.
2. Importantly, that the float height does not cause the fuel level to sit higher the bridge mentioned earlier. This would cause fuel to overflow into the carb neck at idle and cause an over rich mixture and rough idling.
Hope this helps
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Alan Dibley
Prolific User
Username: alsdibley

Post Number: 165
Registered: 10-2009
Posted on Thursday, 20 September, 2018 - 03:54 am:   Edit PostDelete PostView Post/Check IP

Hi guys and gals, I think I have been a victim of the problems caused by ethanol in petrol. Recently there has been a slight smell of petrol around the rear end of the 'T' - I put it down to an imperfect seal on a spare can.

Today (after filling up to top!!!) the smell made me look under the car to see a drip, drip, drip leak. Onto the ramp - it's coming from the Purolator filter bowl - wipe the bowl clean to get a better look - it's now a fountain from a small hole. The entire village smelt of petrol while I clamped hoses an drained the filter and pipes. There was a neat round hole which looked as if drilled by an expert (see the recent ISS incident). When dismantled, the bowl filter also had two tiny black areas which were holes in the making. Temporarily fixed by plugging with tiny screws + sealant. The bowl is aluminium and the inside surface is spotlessly clean as if etched (by the ethanol?).

What's the permanent cure? A whole new filter assembly?

Alan D.
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Omar M. Shams
Grand Master
Username: omar

Post Number: 1673
Registered: 4-2009
Posted on Thursday, 20 September, 2018 - 04:32 am:   Edit PostDelete PostView Post/Check IP

Dear Alan,
that filter bowl assembly either needs a new bowl or a replacement filter assembly (not necessarily from a Rolls-Royce). Remember it is just a device to ensure petrol reaching the carbs is clean. If it says Cartier on the box or Land Rover - who cares.

If you can repair the old bowl (by brazing/welding) when removed from the car and washed/flushed dried, then great.
otherwise a used one will do the trick.
Good luck and see you in Birmingham in 2 months time.

Omar
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Mark Aldridge
Grand Master
Username: mark_aldridge

Post Number: 567
Registered: 10-2008
Posted on Thursday, 20 September, 2018 - 04:36 am:   Edit PostDelete PostView Post/Check IP

Alan, try either Millers VSPE or Tetraboost. Both supposedly prevent ethanol corrosion, and the octane boost certainly works, particularly the Tetraboost. I use Tetraboost in my Healey Sprite and my Crewe cars and Vspe in my 1500 Midget and Merc 230E. Only downside is cost ! I have had 3 filter seals fail due to ethanol.
Mark

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