Petrol "stretching"

jimgoose

dar83 wrote: »

Depends what you're running really, for certain cars 95 octane is far from just perfect.

104 RON be de jab. Savage boo outta her lad!

jimgoose

CJhaughey wrote: »

Japanese pump fuel is 100 octane, some Jap imports don't like the junk we get here.

Most forecourt petrol in Japan is 96 RON. Fast and Furious people of course need to apply elsewhere

fryup

is this basically diluted petrol ??

jca

fryup wrote: »

is this basically diluted petrol ??

Yep:D

jimgoose

RandomAccess wrote: »

Would this affect Turbo or N/A cars differently?
Due to differences in compression etc?

No. That's accounted for in properly configured turbo/supercharged setups.

coolbeans

Anjobe wrote: »

Kerosene is the heavier, but they are both hydrocarbon fractions of petroleum and as such are miscible in all proportions.

Miscible. New word. Noice.

PADRAIC.M

Cost 3k of damage to a car in our garage today 3 year old car!

dgt

So, TVO is making a comeback..... :cool:

jca

dgt wrote: »

So, TVO is making a comeback..... :cool:

Decat her Laaad to get that lovely aroma:D

seamus

Presumably the well-known garages are OK for this (Topaz, Maxol, etc) as their petrol will be coming from a single source?

It's the "Murphy's service station" and other random places you'd need to watch out for, especially if they boast petrol prices consistently 3c+ cheaper than every other local garage.

fryup

they say a knocking noise is a symptom of this....

is that the pistons firing out of sequence??

Cerco

seamus wrote: »

Presumably the well-known garages are OK for this (Topaz, Maxol, etc) as their petrol will be coming from a single source?

It's the "Murphy's service station" and other random places you'd need to watch out for, especially if they boast petrol prices consistently 3c+ cheaper than every other local garage.

It would be interesting to know if the contamination occurs before or at the filling station. Anybody have views on this?

Tea 1000

seamus wrote: »

Presumably the well-known garages are OK for this (Topaz, Maxol, etc) as their petrol will be coming from a single source?

It's the "Murphy's service station" and other random places you'd need to watch out for, especially if they boast petrol prices consistently 3c+ cheaper than every other local garage.

Not necessarily, there were a few main branded ones shut down due to laundered diesel, so I assume there's a similar percentage selling this muck in petrol also.

H3llR4iser

...and, that would explain why when I refuel at a specific couple of places, the 159 goes like sh1te. Good to know (and shame I can't say what places they are. In Cork anyway...)

pred racer

dgt wrote: »

So, TVO is making a comeback..... :cool:

I must dig out the old Massey 20

Gazzmonkey

fryup wrote: »

they say a knocking noise is a symptom of this....

is that the pistons firing out of sequence??

The knocking aka pinking is caused when the fuel ignites before the piston has fully completed it's compression stroke as far as I know.

When compressing the fuel, heat is created... this can actually cause the fuel to ignite before the spark hits it.

Lead was used to stop this in the past but it's octane that's used in more modern cars. hence the term 'unleaded'

Open to correction

ianobrien

Gazzmonkey wrote: »

The knocking aka pinking is caused when the fuel ignites before the piston has fully completed it's compression stroke as far as I know.

When compressing the fuel, heat is created... this can actually cause the fuel to ignite before the spark hits it.

Lead was used to stop this in the past but it's octane that's used in more modern cars. hence the term 'unleaded'

Open to correction

You're right for the knocking part in that the pre-ignition of the fuel during the compression stroke causes the knock as the explosion is trying to force down the piston, while the crank is trying to force the piston up.

The engine is designed for the explosion of the air/fuel to happen when it decides (spark plug) at a set moment in the rotation for optimum power/economy. The use of kerosene alters the fuel properties causing it to ignite early during the compression sequence.

The only part that you're incorrect about is the octane.

<Science alert> Octane is a either a long straight chain alkane (n-octane) or a branched alkane (iso-octane) organic molecule. It's used to determine two points on the octane scale (80RON - n-octane; 100RON - Iso-octane) measured with a variable compression single cylinder engine. Tetraethyl lead was used to stop pre-ignition in the past but now they use other organomatallic compounds, nickel complexes I think. </Science alert>

Chimaera

There are no organo-metallics used for knock control these days for more or less the same reasons lead was banned: air quality issues and fouling of catalytic converters. One of the more popular ignition enhancers these days is ethanol.

Octane rating is essentially a measure of how quickly the fuel will light when exposed to a spark; it's also a measure of resistance to self-ignition. So a higher octane fuel will resist self-ignition while lighting faster once the spark fires.

ianobrien

Chimaera wrote: »

There are no organo-metallics used for knock control these days for more or less the same reasons lead was banned: air quality issues and fouling of catalytic converters. One of the more popular ignition enhancers these days is ethanol.

Octane rating is essentially a measure of how quickly the fuel will light when exposed to a spark; it's also a measure of resistance to self-ignition. So a higher octane fuel will resist self-ignition while lighting faster once the spark fires.

I have to disagree with you on the octane rating. Its a scale with two set points with the two octanes fixed at 80 & 100. I used to work in a lab in an oil refinery and tested petrol enough of times! The instrument we used was a single cylinder engine with a variable compression ratio.

derry

Petrol always contains some ~50% paraffin. Kerosene is approximately 7 parts paraffin 1 part petrol .The old fuels tractor vapour oil TVO in the past such as world war 2 was used in tractors which had compression ratio of ~6:1 and was spark ignition engine that was nearly a diesel engine . The tractors would use high percentage of petrol on the TVO fuel when running light such as going from A to B .Then in the fields the tractors would use TVO with higher percentages of Paraffin in it as paraffin fuel is more suitable fuel for hard work .

Modern cars with a compression ratio of 10:1 will not want a higher paraffin content as it wont burn so well and will cause more carbon build ups and the fuel will have less octane .Its mostly the CATs that will clog up rapidly as the paraffin will ensure more unburnt fuel exits the engine either not burnt fully or still burning when it gets to the CATS. If Cats get too hot this will destroy them .If cats get too much carbon build up in them that wrecks them . If you suspect the fuel has 10% kerosene in it the smell of the fuel will often give it away .If you take a sample of the fuel there are ways to verify if there is too much paraffin in it but that isn't easy for the joe soap to do its something the fuel laboratory can do best .

Also 100% pure kerosene will run in old diesel engine such as my 1993 Toyota Carina 2l diesel engine as my friend proved clocking up 200,000 miles using that fuel in his diesel Toyota Carina . Modern diesels with common rail will often not work well with kerosene as the fuel pumps wont be lubricated from kerosene fuels and the common rail might get issues

So adding 10% kerosene to petrol is looking similar to adding ~10% diesel fuel to petrol. Older petrol cars especially big engines with fewer electronics with less compression from worn pistons might easily ignore the kerosene effects might even get better MPG .
The modern cars with newer better pistons with higher compressions would be more likely to experience ping knocking and even melted holes in pistons from lower octane fuel .

In third world countries the petrol's will often have a higher paraffin contents as those countries can import cars with no cats . The diesel fuels will also have high sulfur content that wrecks the modern diesel cars Particle filter..

Ethanol fuels have a very high octane value .Adding more ethanol to the fuel will increase the octane . So if you suspect that you got stretched fuel then adding Ethanol to the fuel will counteract this . A few years ago this was easy just put some E85 fuel in the tank. Nowadays the ROI doesn't sell the E85 fuel as the government removed the subsidy of lower tax and the fuel if sold now would cost closer to €2 a liter .The only source for ethanol is home heating sources that sell it for €4 a liter in small amounts or €2 a liter if you buy 1000 liters of it

For criminals to add ethanol they can source it probably for 80cents a liter and add it to the fuel . On average most cars wont notice ~20% ethanol in the fuel other than the engine will be more perky and often will have extra BHP ,however it often will run cooler and be tricky to start in the cold morning's and smell like brewery in the cold morning starts . Also the ethanol will reduce the MPG as it less MPG fuel but burns much cleaner than petrol so often will clean out the carbon deposits on engines .

Methanol is similar in qualities and prices in bulk to ethanol but it attacks aluminum parts in the engine with vengeance. Methanol race car drain the fuel from cars in between races as it is so corrosive . Methanol fuel will add lots more BHP to suitable high compression engines and some extra power to normal car The other ways to raise the octane in fuel is to add chemicals such as metals such as lead or other fuels like toluene. The modern cars cats will be destroyed with lead solutions .

The racing cars with higher compressions like ~12:1 will use petrol fuels with higher toluene content in it . Buying some racing fuel and adding it to the stretched fuel might also help but it too burns slowly inside the engine and is ejected outside the engine in the cats . Modern Petrol has often got some 10 to 20% toluene in it smells like paint thinners .

Modern cars can it seems run on 100% toluene fuel but the exhaust fumes stink to hell and back.That fact was found out when the Australian petrol companies not having to pay tax on toluene fuel supplied some parts of Australia with 100% toluene fuel and customers complained about the awful smell from the exhaust emission .

In petrol production the oil companies are allowed some lee way on many items they add or subtract from the fuel .The 5% ethanol fuel they add to modern Irish fuel can vary considerably from ~7% down to ~3% . Toxic benzine can vary from ~0% to ~5% best I can tell but often seems to be 1%. Toluene content can vary from from ~5% to ~50% and looks like it mostly ~30%. Paraffin can vary from ~30% to ~60% best i can tell ~20% seems to be the norm . The other components like Naphtha and various petrol's components can vary a lot from batch to batch . Its not always the petrol retail outlets that do the old trick of adding saw dust to the bread to stretch it out there exists many opportunities at the fuel making and fuel blending parts of the fuel supply.

As a rough rule the fuel ROI is probably the worst quality in central Europe with only places like eastern Europe and Greece with possibly worse fuels . Its good for car makers they get to wreck cars and people got to buy more new cars so pressure is on governments to look the other way when bad fuels enter the system . The old diesel fuels allowed many diesel cars like Mercedes Toyota Nissan to get ~1,000,000 miles .That was bad for car makers .The same makes like Mercedes Toyota Nisan the newwer cars with new diesel fuels are often clapped out now at ~300,000 miles . They modern diesel engines have removed much of the excess diesel to get better MPG and that leaves less lubrication for the engines so they wear out more .Also the fuel quality is severely impacted with the year ~2000 onwards recent addition of ~7 to ~10% bio fuel which also helps increase engine wear problems .Fuel suppliers Having successfully got rid of the ~1,000,000 mile diesel engine now the target is to get rid of the ~500,000 miles petrol engines and get them to be worn out at less than ~200,000 miles .

The days of good fuel are probably over and the car maintenance insurance companies wont insure for fuel issues .Now the insurers tell you to sue the Fuel suppliers . So from here on in your gonna have to take sample of fuel from every fill you make or you wont be able to sue the fuel suppliers .

Thats the real story of Irish fuels they dont want you to know

Derry

Hisfan

Chimaera wrote: »

I wouldn't say that. It's a different sort of damage.

Laundered diesel does its damage because the acid used to remove the marker dye is rarely washed out properly. This will cause a lot of damage to the fuel system components. It'll also tend to have more water in it, again because they're not that careful about removing it during processing.

Kerosene in petrol will mainly cause coking because it's not burning the kerosene properly. So you get carbon deposits in the head, and probably in the cat too. Too much of this will eventually cause trouble but it's more easily undone and if it's caught in time it's reversible. Acid and water damage to DFIE is permanent and cumulative.

As for spotting it, the smell should be a bit of a giveaway. Kerosene has a pretty strong smell and it's very distinct from the smell of petrol so if there's any meaningful amount of kerosene in petrol you'll probably get a whiff of it while filling up.

Does anyone know, or have experience of keresone damage to a petrol engine. I drive a VW Polo 1.2. The car was chugging and losing power and the "emission control / engine management lamp" light came on. Rang the main dealer (where I bought car) and they said bring the car down. Car was parked up for two days and I drove the 100kms to garage today. In the first 20kms into the journey the car lost power a little at a junction but behaved perfectly normally for rest of journey. No warning light on dash and no loss of power.

Garage say car failed the three tests they do and say failure of these tests is consistent with sub-standard petrol issue. They say next step is to send samples to the lab for testing. I feel sure they want to blame petrol issue for engine damage and want to change engine in car (coz pistons can't be removed for cleaning).

Is it possible to have keresone-in-petrol-issue and for symptoms to go away? Coz the symptoms really didn't seem to be effecting the car today.

However, with garage saying car failed tests and if lab results come back with bad news, will I have to pay for new engine? I'm concerned the garage are jumping on the "kerosene" bandwagon coz it's all over the news.

Confused woman driver!!!!!

Chimaera

ianobrien wrote: »

I have to disagree with you on the octane rating. Its a scale with two set points with the two octanes fixed at 80 & 100. I used to work in a lab in an oil refinery and tested petrol enough of times! The instrument we used was a single cylinder engine with a variable compression ratio.

I'm aware of how it's measured. I was pointing out why it's measured and what it actually means for the use of the fuel in an engine.

Havaianna

HI

I also have a VW Polo 1.2 petrol facing the same issues. Firstly the car just lost power seconds after the engine light came on. It started up again fine with no light on but there was some noise coming from the engine. Brought it to garage for Diagnostic and was told I could not drive it and they were investigating the engine. Have been without my car for 2wks now. I have now been told VW were testing the fuel and queried where I buy from. since this I have become aware of "petrol stretching" articles in the media and the effects on engines is very similar to what appears to be wrong with my car. Just like Hisfan am beginning to wonder is it a VW fault or a result of bad fuel??

pudzey101

so long storys cut short , wheres the best source of fuel ?? likes of tesco,maxol,amber topaz etc ... ??

mikeecho

For the past 2 and a Half tanks of petrol (from my regular station) for my 2L car, it has been slow to start.
Thought that the fuel pump was on the way out, as there was excessive cranking on startup when cold, but ok when the engine was hot.

I also noticed some smoke from the exhaust, but again thought this was form the pump failing and excess petrol being drawn during startup.

Anyway filled up yesterday at a Topaz, from a near empty tank, and within hours the symptoms of excessive cranking were reduced a lot.

I'm begining to think that the petrol may have been streched in my last 2 1/2 tanks.

Hopefully damage hasnt been done, i always add dipetane to every tank of fuel, petrol or diesel.
So i'm hoping that the Dipetane added a some lube and prevented something more serious.

The station i used has since upped its petrol prices by 2c.

mikeecho

pudzey101 wrote: »

so long storys cut short , wheres the best source of fuel ?? likes of tesco,maxol,amber topaz etc ... ??

Probably in petrol stations that are owned/operated by the actual fuel company, rather than franchised.

as per my previous post, my latest fill was a station that is owned and operated by topaz.
and things seem ok since.

Havaianna

Anyone have any idea of how long it would take the damage to occur.? MY last 5 fills were with the same station and considered reputable.

foxy farmer

Customs and Revenue raided an operation recently where illegal vodka was being bottled and ethanol was being added to petrol. So theres a element of subversive activity involved.

Technoprisoner

Dartz wrote: »

Kerosene drops the octane rating of the fuel.

Melting pistons I'd well believe if it's causing the engine to detonate. But the car's ECU should detect the misfire and either flag it with a flashing CEL - or knock back the spark. And then flag it. Especially since modern engines have such high compression anyway.

Carbon buildup is nothing a good hard shoeing won't solve. Petrol engines need to be run at more than a constant 1500rpm to get the chamber temperatures and pressures high enough.

Besides, IIRC, Dipetane is a kerosene formulation?

by the time the ecu detects the engine detonating it is usually too late...you are talking milliseconds...i had a car melt a piston due to ****e fuel before

dr.fuzzenstein

Gazzmonkey wrote: »

The knocking aka pinking is caused when the fuel ignites before the piston has fully completed it's compression stroke as far as I know.

When compressing the fuel, heat is created... this can actually cause the fuel to ignite before the spark hits it.

Lead was used to stop this in the past but it's octane that's used in more modern cars. hence the term 'unleaded'

Open to correction

The lead was also used to protect the valve seats from wearing. After the lead was removed, hardened valve seats where fitted to newer cars. If you have a classic, you will know all about it and your choice is to faff around with additives or get the head converted to take unleaded.