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MG MGB Technical - Ethanol???

Before anyone gets hot under the collar, I know this is a V8 but it's just as applicable to any HIF equipped MG.
About 3 weeks ago I removed my inlet manifold to get it powder coated. I checked over the carbs, mostly just the float height then bagged them ready for re-assembly, which I did last weekend.
When I started it it ran like the proverbial "bag of nails".
The plugs were black and I couldn't lean out the mixture. So off with the carbs to strip them.
Every piece of rubber was brittle and fell apart. The critical "O" ring on the choke barrel was the culprit. Without that seal working it's like running on full choke and more, all the time. Bear in mind these carbs were fully re-built less than 6 years ago!
HIF's have this critical "O" ring plus another on the jet adjustment screw. Loss of the spindle seals wouldn't have a great effect unless the spindles are badly worn. After all, HS's don't have them. HS's don't have all these critical rubber seals either. I only remember the one on the jet pipe to the float chamber.
Letting them dry out probably helped to show up the deterioration.
But it's a warning, a re-seal job is almost becoming a service item. If the Ethanol level goes up, deterioration will presumably be much faster!
Allan Reeling

Apparently, Esso super-unleaded doesn’t have any ethanol - yet.

That’s what I use in everything - lawnmower, strimmer, chainsaw, motorbike and the B. Having said that, the B does seem to be running a bit rich. It has a single HIF6, so I may have to look at my spare HS6s if it starts being a problem.

I have already had problems with the fuel pick up pipe in my strimmer disintegrating and the carb diaphragm on the lawnmower failing. That was before I switched to super-unleaded.
Dave O'Neill 2

Could piss-poor rubber be contributing or even the cause of these problems. I think some rubber parts might be better now but 12 years ago I had lots of problems with fuel hoses and from then until very recent lots of other problems with other rubber parts that don't see petrol of any sort.
Nigel Atkins

See my previous thread Allan, I rebuilt mine after 4 years with little or no use. Both kits were Burlen so quality shouldn't be an issue (hopefully) There was a lot of rubber particles throughout from cheap fuel hoses elsewhere. The Choke rings looked ok, but the assemblies were easy to remove so I suspect they weren't sealing (certainly on the rear carb)
Pat Gregory

There's not been any reports from America of problems caused by ethanol that I'm aware of, and not long ago I specifically asked, and they have had far more exotic brews than we do for years. What fuel do you use? Whilst all UK fuels may have contained 0% to 5% ethanol for some time, only that from pumps specifically labelled 95 E10 can contain up to 10%. Specific brands of fuel can vary round the country, for example in 2011 from enquiries to suppliers:

BP: Ethanol is added at 5% to unleaded petrol at all sites across the UK. BP Ultimate (super unleaded petrol) does not have Ethanol added, except in the South West of England.

Esso: Ethanol is added at 5% to unleaded petrol at most sites in the UK. Esso Super Unleaded petrol does not contain Ethanol, except in the South West of England (Devon & Cornwall)

Shell: Shell has repeatedly refused to answer the question. It is therefore an assumption only, that all Shell petrol should be considered to contain 5% Ethanol.

Texaco: Ethanol is added at 5% to unleaded petrol. Texaco Super Unleaded petrol does not contain Ethanol.

Total: Ethanol is not added to any Total fuel (including standard unleaded petrol). Except in the North West and South East of England.

There has been EU and UK legislation to keep 97 and higher at a maximum of 5% for some years, which as far as I'm aware is still applicable. I've always run my V8 (HIFs again) on supermarket 95, and - so far! - haven't had any fuelling problems.

Rubber these days is just rubbish. Coolant hoses, brake, clutch system and suspension seals only lasting five or six years at best, none of which come into contact with ethanol.

Like vapour-lock reputedly causing running and starting problems, which with our systems I don't even see is possible, it's like rocket launches in the 60s being the cause of bad weather - handy for blame.
paulh4

The other element which I forgot to include earlier is heat. V8's especially get very hot, that coupled with poor rubber would account for the spindle seals, as they don't encounter much fuel as such.
Yes some of the rubbish rubber I've had experience of, but one would hope, as Pat mentioned, that Burlen actually source good quality items. But having said that, there are available more Ethanol resistant rubbers.
Paul and Dave, interesting regarding the inclusion of Ethanol by various manufacturers, but sometimes you don't get the choice, more so if you are in the S W!!
Allan Reeling

V8s DO get hot! So much so that in weather like we have been having recently I can hear the fuel boiling in the float chambers at switch-off, and a plume of vapour pouring out of the vent hose, enough to completely empty them I'd say going by how long the pump chatters at the next cold start. Stop/start on the M6 last week in the middle of the day had the fans going all the time. They were bringing the coolant temp down below N on the gauge, and should have switched off way before then, but I suspect the heat in the engine compartment above the thermostatic switch was travelling down into the sensor and keeping it on, even though the coolant itself was lower.

My carbs have only had needles, jets, float valves and one float in the 24 years I've had it, so hopefully I have good rubber! How recent are your carbs rubber parts (so to speak)?
paulh4

Same with the fuel here
They are allowed up to 5% ethanol without telling anybody
Same as you there with the E10
We have several lots of fuel

Std unleaded
95 Premium
98 Premium
Std E10
95 E10
and some places sell- E85

Our std fuel is supposed to be 91 but it's only a recomended spec and I'm sure most makes are lower but topped up to the max alowable 5% ethanol to stop everyone driving around pinging away

Don't know why they can't just say our fuel is full of rubbish, buy the better stuff
There is a rumour here that the lowest octane fuel available will be 95 soon ,the std stuff is going to get the flick---we'll see
William Revit

I bought the V8 in 2012, spent 6 months doing body repair etc., then re-built the engine and the carbs will have been done then, so probably no more than 5 years ago. There didn't "seem" to be an issue until I took them off and they therefore dried out. So hopefully as long as yours stay wet they won't start leaking, but keep an eye on any tendency to run rich. It was alarming to see the state of them when i stripped them down. Burlen didn't seem surprised though!!!!???
Allan Reeling

Paul you forgot Tesco and my favourite fuel Tesco Momentum 99, very widely available in the UK expect Northern Ireland. "We don’t currently have a supply terminal that is able to produce our high octane base fuel to blend with our exclusive additives in Northern Ireland".

"How much ethanol is in Tesco petrol
Under UK legislation large fuel producers have a mandatory obligation to use a certain percentage of fuel from renewable sources. The renewable fuel used in petrol is ethanol, typically produced from sugar or starch crops such as sugar cane and maize. Dependent on location and supplier, UK petrol contains between 0 and 5 percent ethanol (produced in compliance to BS EN 288:2012)."

https://www.tesco.com/help/petrol-stations/

I too have found the bigger multi-national oil companies very closed about their products.

Nigel Atkins

Personally, and I could well be wrong as I often am, I can't see that a small non-scientific/medical/aircraft company like Berlen would be able to avoid, whether they wanted to or not, the standard quality of bought-in components like rubber seals.

The race to produce products as cheaply as possible, encourage by consumers like us, has had it consequences.
Nigel Atkins

Didn't forget Tesco, it wasn't part of the survey that someone else did, and a masterful piece of non-information from them.

I did see another statement from the petroleum industry that they could more than meet legislative requirements for renewables with bio Diesel and up to 5% in petrol, so had no plans to produce E10. Which like anything else can change at any time of course.

Like anyone else Burlen could opt for quality ... if they wanted to. I'm not impressed with then in any case. Ignoring questions about a suspect fan switch from them, and a pal who bought a pump rebuild kit from them found some of the gaskets didn't quite fit and they leaked. When he queried them they said "Oh yes, we have changed some of them to fit different pump bodies but didn't change the part number". In the end he had to send off the pump to them to be rebuilt.
paulh4

Paul, sorry I read it as your inquiry and survey. Yes Tesco have taken a type of line that, IIRC, Shell used to give before they stop giving any info.

Again IIRC there was formerly a suggestion that Tesco 99 was ethanol free whether this is still the case (or ever was) I don't know.

Try asking about engine and gear oils and the info goes vaguer.

Coincidence or not, since ethanol has come in there's also been a suggestion that I've lots some of my looks, this is of course rubbish . . .
Nigel Atkins

Little bit off subject but---
Back when we were racing Chevs we were running a fuel called BP-K, it was 100 octane rated, ran the same injector sizes as petrol but had a real strange aroma like a mixture of thinners or something like that, We used it for it's cooling qualities similar to methanol but didn't need the extra fuel that methanol requires--Forced in a way to use it because with a 100 lap race the fuel tank wasn't big enough to get to the finish on metho
Had a hell of a go to start with with rubber 'o' rings and things melting instantly but replaced everything, metal fuel lines ,copper and nylon washers and finally got on top of it
One day in the pits an opposition team member-probably the only other team not using metho- came over to borrow fuel as they had run out
Told him yep, ok but warned him of the melting rubber situation and he said he'd take the punt on it
Well about 5-6 laps into the race you should have seen it, his car was like a sprinkler with little flames spurting out everywhere- he pulled up and they doused it with water thinking it was a metho car which sort of looked funny in a way with little rivers of flame running down the track, then got it out with extinguishers
Lesson learnt by them--fuels are not all the same ,100 doesn't mean it's the same 100

Just thought I'd share that eventful memory with you
willy
William Revit

just thought I'd give it a like

thanks Willy
Pat Gregory

Interesting Willy, and scary, in equal measure!!
Allan Reeling

Many of us have recorded rubber problems resulting from the ethanol content of fuel - less well recorded are the corrosive effects of water and the organisms which now can thrive in fuel. The marine world has learnt to deal with fungal growth in diesel fuel - ethanol has migrated this problem to petrol and the classic world would be well advised to take steps to prevent this when laying up their cars for lengthy periods.

Apparently modern daily drivers are not immune either.
Roger Walker

The American Evironmental Agency largely debunked water problems in ethanol fuels some time ago. I'd give the link but it is no longer active, but must be buried in their archive somewhere:

"Water vapor, however, dissolves in gasoline very slowly, even at very high humidity. For example, at a constant temperature of 100 degrees F and relative humidity of 100%, it would take well over 200 days to saturate one gallon of gasoline in an open gasoline can (assuming the only source of water is water vapor from the air). Water absorption from the air is far slower at lower temperatures and humidities. (At a temperature of 70 degrees and relative humidity of 70%, it would take over two years to saturate one gallon of conventional gasoline in the same gasoline can.)
Water phase separation in any gasoline is most likely to occur when liquid water comes in contact with the fuel. (Water in the form of moisture in the air will generally not cause phase separation.) Water which is in solution with gasoline is not a problem in any engine, but as a separate phase it can prevent an engine from running or even cause damage. Since oxygenated gasolines, however, can hold more water than conventional gasoline, phase separation is less likely to occur with oxygenates present."

This all came about from a discussion on brimming the tank over winter, about which the EPA document says:

"... gasoline should not be stored for long periods of time, especially during seasonal changes which usually have large temperature changes associated with them. ... If it is unavoidable to store gasoline for a long period of time, one should be sure that the tank (is) full to prevent condensation of water from the air ..."

But quantifies the risks:

"For example, assume a tank containing conventional gasoline contains only one gallon of fuel. Assume also that it is closed while the outside temperature is 100 degrees F with a relative humidity of 100 percent. If this tank is left sealed and the temperature drops to 40 degrees F, water will likely condense on the inside of the tank, and dissolve in the fuel. In order for enough water to condense from the air to cause gasoline-water phase separation, however, there must be approximately 200 gallons of air per gallon of fuel over this temperature drop (100 to 40 degrees). Since oxygenated fuels can hold even more water than conventional gasoline, it is even more unlikely that enough water will condense from the air to cause gasoline-water phase separation."

In other words phase separation is less likely in fuels containing ethanol than without! As far as absorbed water goes it says:

"Water in solution operates as no more than an inert diluent in the combustion process. Since water is a natural product of combustion, any water in solution is removed with the product water in the exhaust system. The only effect water in solution with gasoline can have on an engine is decreased fuel economy. For example, assuming a high water concentration of 0.5 volume percent, one would see a 0.5 percent decrease in fuel economy. This fuel economy decrease is too low for an engine operator to notice, since many other factors (such as ambient temperature changes, wind and road conditions, etc.) affect fuel economy to a much larger extent."
paulh4

Poor running condition when hot has been a huge problem for my MG-B in the summertime as fuel in the U.S. has a 10% alcohol content. My MG has A/C which adds heat to the engine compartment and load to the engine, making things worse.

I was traveling recently in Mexico where there is no alcohol added to the "Premium" grade gasoline. Engine idle was stable and the car ran well even though the ambient temperature was close to 100°F.

I checked the boiling point of U.S. fuel with 10% alcohol and it is listed at 178°F. After a drive in the heat of the day, I flashed the temperature with the thermometer gun and the front carb bowl was running at 180°F and the rear at around 190°F (HS4s). The fuel boils up through the jets, everything goes rich and it is difficult to keep the engine running at idle.

I have a Nissan X-Trail in S. America that sat for 3 months with gasoline that contained alcohol. The fuel gauge stopped working and then the car lost power. Upon removing the gauges and fuel pump, I found that the rust was so severe that the float rods for the gauge were severed and that the entire casing of the in-tank fuel pump was rusted away. The spring in the fuel pressure regulator had rusted which lowered to fuel pressure and accounted for the lost power. That was an expensive repair!
Glenn Mallory

I have found the o-ring failed on a number of occasions, but never had a repeat one on the same car. I suspect it is often overlooked when carbs are "overhauled".

As for ethanol, as I have noted before, when our local petrol station changed to E10 in 2012 I decided to be a guinea pig so we could give informed advice to customers and have used it as our primary fuel.

So far, after 6 years, still no issues in any of our fleet (B, midgets, MGFs). Unless you count the dropped valve in the B in the second special stage of the last rally it was in. Conspiracy theorists probably would, but I'm more inclined to think it was the result of 10-20 years of chasing my sons in autocross events, in which I have found that (on the courses we use) holding it in gear and ignoring the tacho being firmly on the 7k stop for what seems forever, (and no doubt the beginning of a little valve float) gains a useful 1/2 second, which is just enough to beat said sons in the K Midget. By comparison when rallying it has a sedate life and never sees the tacho stop. (Almost, but not quite).



Paul Walbran

Paul,
I do my own carb overhaul so can guarantee that everything was renewed.
5 years I should imagine is a shorter life span than the original seals, whether down to Fuel or poor rubber, it does make one wonder about the wisdom of overhauling carbs on the grounds of age alone!.
Allan Reeling

Agree with that - "If it ain't broke ...". Things are really best left alone these days, JFDI :o)
paulh4

Yes, should certainly last better than 5 years!
Paul Walbran

There are links to reports on the MG Car Club Midland Centre website which make worrying reading. One is commissioned by the UK government.
I personally have had no trouble with rubber or brass erosion running on supermarket 4* (95 Ron). My carbs tend to overflow after the car has been standing despite having PTFE tipped needles in the float chambers, but it soon settles down.
Paul Hollingworth

The reports all seem to be saying what "could" happen. I have yet to hear of any problem that can be directly attributable to Ethanol either in the US or UK. It's comforting that Paul W has run several cars for several years with no ill effects. My instinct is that most problems are more to do with poor quality or manufacture.
Michael Beswick

Michale, I think you are probably correct regarding quality. The archives of this and similar sites must be rammed with tales of poor product, particularly rubber.
I threw the ethanol reference in, as that was put to me by Burlen!
Allan Reeling

Further to my previous comments, and reference of others, I've had several instances lately of over-flowing float chambers caused by "debris". On examination this debris was black! There is only 400mm of flexible hose between filter and carbs, but I'm left to assume it is the source. This is supposedly good quality Gates fuel pipe!
Allan Reeling

This article is particularly interesting read regarding fuel hose.
http://www.volksbolts.com/faq/fuelhose.htm
One disturbing section notes the re-labelling of inferior (J7) fuel hose as more ethanol resistant R30 J9.
Allan Reeling

I have a mid-'90s Honda 650 motorcycle.

The handbook says that the use of fuel containing ethanol will invalidate the warranty.

They must have a reason for saying that.
Dave O'Neill 2

Dave &
I have a friend with an early 911 Porsche SC with mechanical, non feedback fuel injection
It hates any fuel with ethanol, he now runs it on 98 premium all the time
If he runs it on E10 or any thing lower than 95 of unknown quality it simply won't hook into it properly
Here a year or so ago I was following him at a reasonably quick pace out on the highway in the early hours of the morning and I could see the muffler accross the rear of the car glowing red hot and when he pulled up it had actually melted the underside of the rear bumper bar---It was running too lean/hot on the ethanol laced fuel--Running it on good98 there isn't an issue
William Revit

Alan-There was a thread on the MGOC that after much testing discovered that the ethanol resistant membrane of Gates Barricade fuel hose could be scratched off with your finger nail. Inserting the pipe over the ferrule of the float chamber caused the membrane to come off and block the carbs (periodically).

Dave: Yes the theory of ethanol damaging "parts" is sound. So a manufacturer might well add that in as insurance. Most of the discussion seems to be about parts "deteriorating". I can see that if ethanol runs hotter and the there is no ability to adjust this (timing?) it could be a problem but of a different nature.

Willy Does the addition of ethanol effectively reduce the octane rating? Does that in turn cause it to run hotter? So does it follow that adjusting the timing would prevent this? Tho far simpler to use 98 I accept!

AFAIK Modern cars can run on pretty much anything as the ECU adjusts the timing to suit??
Michael Beswick

From what I can determine from the "volkbolts" article, petrol with ethanol added needs to be mixed with air at a different, lower, ratio than petrol alone. Which presumably, with carb fed engines, means the burning mixture will be leaner and hotter, if tuning was initially done on non-Ethanol petrol.

My repeat flooding O/S, carb issue (V8) was solved when I stripped them, yet again, and found the connecting pipe was actually R7 (older standard).

Michael, that makes sense as when my N/S carb floods (apart from the sunken NEW Burlen float that is), it is always following re-connection of supply pipe!
Allan Reeling

Michael
your question--
""Willy Does the addition of ethanol effectively reduce the octane rating? Does that in turn cause it to run hotter?""

As I see it, I believe if the fuel is fresh, the ethanol actually increase the octane rating--BUT If there is for eg. 5% ethanol in there which is the legal max. allowed here before going to E10 fuel-- then all is probably ok, but the ethanol part goes off quickly leaving 95% petrol and 5% of dead stuff which shows up as milky fuel---When it's older like this (and it doesn't have to be very old) is when the problems arrive and it's like running a car lean (95%)mixture but with water injection (the other 5%)to stop it pinging , the result being poor performance and a hot burn
Richening the mixture a tiddle is probably the answer really but better fuel is best if available

willy
William Revit

I gave up on rubber O-rings years ago because they don't like ethanol, and become hard and brittle. If possible, use FFKM (Perlast) O-rings. They are a bit more pricey, a little harder to find, but being made of a rubber form of PTFE material that has a high temperature stability that ranges up to 620 degrees Fahrenheit (327 degrees Celsius), they will withstand virtually any chemical or environment that any pliable seal is required to endure. If you cannot find them, then use O-rings made of Viton (Buna-N) material.
Stephen Strange

If the Gates is multi-layer Barricade these have a very thin inner layer, and if it has to be pushed onto the ports and especially the barbs of fuel filters it shreds, as in the attached. You need to use a hose size that slides on easily, and rely on clamps to seal. Or a simpler hose.


paulh4

This thread was discussed between 11/07/2018 and 30/07/2018

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