Petrol quality

[Daz1968]

I had a few issues with my mk2 cooper a few weeks ago, it was a little hesitant from low revs, the fuel was probably a few months old but I had used Castrol valvemaster plus, I had presumed this helps the fuel in storage,
Today I went out in the car but added some fresh fuel and it ran faultlessly,
I can only presume fuel was the issue, is there anything better than valve master plus, or am I better just keeping the tank as low as possible and adding fuel for each journey,

Thanks

[Spider]

Valvemater as best I know is only an Exhaust Valve Seat 'saver' and not a fuel preserver.

I'm not sure on what the exact situation is with fuels in the UK, but here in Australia, most brands on guarantee spec for 4 weeks from forecourt delivery. I've found some have definitely gone off in 2 weeks after purchase (not sure how it it was when bought). There are specific Fuel Preservers available. I'm not sure if the fuel retailers offer it widely, but the Mower Shops often have it.

[Polarsilver]

Try Briggs & Statton "Fuel Fit" designed for overwinter fuel in chainsaws & mowers .. i find this works for me when added to fresh UK Petrol..However Fuel Fit will not revive dead petrol.

[mk1coopers]

I’ve now switched from V power to Esso 99 as the Esso fuel is still (supposedly) ethanol free, plus the octane boosted Castrol Valvemaster. If the cars are going to be stood up for for any period of time (which is currently far too often) I also add Lucas ethanol stabiliser before the last drive so that’s in the system too, just in case.

[Peter Laidler]

I had a totally different experience. Slightly different in that I left my RCSport5 in a secure garage in Oct 2019 just before Covid. Half full of the usual Shell fuel. Left there all over Covid, untouched and unseen

Towed car home in March 2021 expecting a full drain down etc etc. Put old battery on (kept trickle charged for 2 hrs a day between times), tried to start car and it burst into life FIRST turn of the key. Totally amazed....... and ran as sweet as a nut.

Someone told me that it was because while the RCS's are a closed fuel system, the fuel will start to do what it does, none of it can evaporate away.

[snoopy64]

Hi,

I must admit I’ve never had a problem with my car standing and I put all kinds of petrol in it, not always ‘super’. I do have a good quality coil i.e. not original and open the plug gaps a little more than the spec sheet says…not sure if that’s the difference…

One of the local garages sells Essar 99 which a couple of my friends say is good stuff but I’ve not used it enough to tell the difference between that and Mr Sainsburys offering

[AndyPen]

I have been removing the ethanol and am surprised how little comes out of the Shell and Esso high octane versions - seems to vary though.

[woodypup59]

Allegedy Esso super has no ethanol at all in the SE of England.

Why they don't guarantee that all over the country I don't know.

AndyPen - what do you do with the removed ethanol - mix it with tonic ?

[surfblue63]

Millers do an additive that combats the effects of ethanol. Millers VSPe Power Plus. I have some but have yet to try it out as I have not driven a Mini for over 2 years.

https://www.millersoils.co.uk/products/ ... ulti-shot/

[AndyPen]

Allegedy Esso super has no ethanol at all in the SE of England.

Why they don't guarantee that all over the country I don't know.

AndyPen - what do you do with the removed ethanol - mix it with tonic ?

I was given this kit and to be fair, it seems to work. I've a special 'safe' place to do it, and I guess it could done with other containers too?

http://www.ethanil.co.uk/how-it-works/

[Polarsilver]

Can you remember that old fashion Petrol smell .. fragrance that informed your 5star was leaking from the Carbs

[tweedy998]

I run 'Tweedy' ('65 998 Cooper) on V-Power with the addition of the Millers 'VSPe Power Plus' and have no complaints. The car is currently running very sweetly indeed after the top-end rebuild and other optimisation I undertook recently.

[mk1]

I run everything as low as I can before laying them up, then add a litre or so of Aspen, or some other alkyl fuel. If I am running a car regularly then I run whatever E5 is available at the time & stick a slug of Tetraboost in every now & again.

http://tetraboost.com/

Before we started doing this we were plagued by cars not wanting to start after a lay off of only a couple of weeks.

All Adam's Pre War stuff doesn't have the same issues, as they were designed to run on anything that was going.

I couldn't imagine a time when I was prepared to get my chemistry set out to remove any ethanol in my fuel. I think I'd rather go electric

[AndyPen]

Lol at Chemistry set boss - it is surprising how hassle free it is once set up. What surprises me most is the variation of ethanol volume in some E5 fuels. Recently the Shell around here has little or none, so if I find that (a lot at the moment) I top up

Good point on the starting issues, and since finding that horrible acidy water in my float chambers in the 970 I always pump out a bit first if its been awhile.

[mab01uk]

I had a totally different experience. Slightly different in that I left my RCSport5 in a secure garage in Oct 2019 just before Covid. Half full of the usual Shell fuel. Left there all over Covid, untouched and unseen

Towed car home in March 2021 expecting a full drain down etc etc. Put old battery on (kept trickle charged for 2 hrs a day between times), tried to start car and it burst into life FIRST turn of the key. Totally amazed....... and ran as sweet as a nut.

Someone told me that it was because while the RCS's are a closed fuel system, the fuel will start to do what it does, none of it can evaporate away.

Peter this seems to be true in my experience, on more modern cars and Minis with fuel injection and a closed loop to the atmosphere fuel system petrol lasts many months longer and often a year or more. In contrast after a few months in the garage my carb Mini runs very sick or won't start on stale fuel in the tank. I once drained it and thought it would be good enough for my Honda lawn mower but that too refused to run properly on it! Also a pain to dispose of stale petrol in any quantity safely....

[mk1]

In all fairness, the above stands to reason. If fuel is enclosed in a pressurised system & is unable to evaporate then it is impossible for the volatile elements to evaporate, so the fuel can't possibly change it's nature.

[surfblue63]

It's not the evaporation with ethanol fuels, it's the hygroscopic nature of ethanol that causes problems. Once the ethanol attracts water it gains mass so sinks to the bottom of the tank, thus causing starting and running problems after a lay up. And of cause it doesn't help with corrosion either.

[1071 S]

Who remembers that, back in the day, it was not unusual to get a good dose of water with a fuel top up due to leaks in the petrol sellers underground tanks.

If your car objected to the new fuel the solution was to dump a pint of metho (methylated spirits ..aka ethanol) into the tank. After a few miles the ethanol would absorb the water and mix with the fuel and everything would be good again.....

Ethanol is not really a villain, more a mixed blessing. It raises the octane rating of the fuel its added to but doesn’t have the energy density of the other hydrocarbons its been mixed with. A modern car (with electronic ignition) can take advantage of the increased octane to more efficiently burn the less efficient fuel. Unable to take advantage of this, we get dudded...

I avoid ethanoled fuels because it costs the same but delivers less mpg...

Cheers, Ian