Hi guys…I plan on putting my S550 away for the winter and was wondering if anyone had any recommendations concerning adding fuel stabilizer? It will go to sleep with a full tank of 94 octane fuel, fresh oil change, and ctek charger. Just not sure what stabilizer to add. Many thanks in advance. Cheers

 

I use Stabil Storage... No issues... even when I don't get the dosage right...

 

get as low as possible and buy ethanol FREE fuel the other stuff should be illegal - its entirely designed to kill off old vehicles and rob you on fuel efficiency

the one thing you don't ever want is ethanol in there - it causes long term detrimental effects, that increase the less you use the vehicle / older the filth is in there damaging it

Note they did the dirty at the switch over and both types std unleaded E10 and super unleaded E5, appear to have a 20% energy density drop to steal more money - increasing mpg by circa 20% rather than E10's mathematically correct 6% drop ethanol has to bring to the party (as energy density of ethanol is lower).

for drivers that leave old fuel in there long term... ethanol absorbs water assisting in corrosion of the pump and injectors etc... but remarkably there are much nastier features they don't want you to understand... it can grow bugs in there, and these excrete acetic acid that leads to erosion of metals, which then assists in the corrosion issues from the water - for older vehicles where pump seals or hoses used natural rubber the ethanol destroys this, then its damage to plastics making it brittle and can crack, expand and deform tanks etc. and lastly its other designed in magic trick - it also separates which can lead to injector pipework blocking with a jelly type mess

think old world petrol 10 plus years back, fairly safe to leave for 3 years (expect a bit of difficulty starting and won't perform as well - but it was still petrol)
modern fuel from the last few years, ought to get 6 months, may get away with longer but not the best of behaviours
ethanol inflected 3 months is a mistake - with it becoming more of an issue the higher the content

top tip - get a decent measuring flask - put in 100ml of petrol and 100ml of water, shake and check how much water now separates out - the difference is your ethanol filth content..

 

Thanks BOTUS…this is very useful indeed. I did some research and it appears the Petro Canada 94 octane fuel I’ve been using this summer contains up to 10% ethanol. Looks like Shell however offers 91 in my region that is ethanol free. I think based on your advice and what I’m reading online now that I’ll run that 94 tank dry and fill up with the ethanol free 91 with some sta-bil for winter storage! Love this forum!

 

Quick update…thanks to BOTUS I’ve been reviewing the Canadian regulations and it seems as early as January 2023 most provinces will require at least 10% ethanol in all products at the pump! Seems the days of ethanol free products are coming to end at least here in Canada. Which is not very popular with folks who have old classics or seasonal drives! Will adding stabilizer during storage help deal with the ethanol?

 

the numbers at the pump's in America display AKI values which shows 4 to 5 lower than the equiv for European Petrol - So 89 octane is normal fuel for std altitudes 0 to 1000 ft in USA ? An W221 S550 with the older V8 won't run any better on higher than "normal" octane rating. If ethanol free is affordable and happens to be a bit higher in Octane - its just a better fuel and a good idea

when UK went to 10% ethanol as the standard fuel for most cars (95 unleaded E10) in Sept 2021 all my bikes and my car's fuel use have gone to pot - the car was doing a 25mpg no problem - it now won't go above 19mpg under identical conditions UK gallon = 4.56ltr not the US gallon = 3.467ltr

does that mean u have 6 pints to a gallon rather than the 8 is supposed to be ? and how the hell did you guys get that wrong ? its a bit like randomly deciding a mile is 300 yards less than it really is cos u can ?

 

its a con job - UK Super Unleaded by law must say E5 at the pump - but that means its allowed to have up to 5% ethanol - it doesn't actually have to contain any - and indeed where I live exxon mobil fuel in my location contains no ethanol at present

check this out - there some silliness on a bike forum as everyone confuses themselves - I tried to explain the world just this morning - remember posh fuel costs lots to make when you include good anti-knock additives as they are big money - ethanol just happens to bring a double whammy as its a waste product that just happens to have a good anit-knock capability - the latest research shows the environmental BS of including ethanol is a LIE it was a marketing trick to steal our money

common misconception about octane

the idea is an engine is developed for use in a certain type of vehicle and expected usage, with a tolerably wide, but pretty boring set of ambient and altitude conditions in mind - as we light the petrol, we then want the flame front in the combustion chamber to run as fast and controlled as possible. So we get a clean burn and max power and torque (as defined in the earlier characteristics of the vehicle and typical use) - Petrol only ever explodes when it's gone wrong - and not many revs later, you have broken rings, holes / melted pistons etc, and the engine is toast.

octane in the fuel slows and help control that burn.... if you put too high an octane it will make less power - not more, as the burn becomes sub-optimal.

modern engines with vastly different combustion chamber design, different materials, cooling systems, injection pressures and injector design, plus more and more sophisticated measurement and control of the engine management (fuel quantity, when it turns up, when the spark happens etc.) all means we can play about a lot. This, alongside fuels that are far more consistent to one another, means we can aim for optimal burn all the time (within constraints of a lack of servicing, bad riding, minor engine irregularity, dodgy fuel etc.). Starting off using good quality, high additive, premium brand fuel closest in spec to the original design means the base is as good as it gets.

Nearly all 2010 onward, high compression, 4 valve head, petrol engines run a design and engine management system that could easily make use of high octane fuels, but as its availability isn't enough, they build a perfectly reasonable alternate fuel engine map so the vehicle can tolerate a wider range of fuels that might be readily available. Its not new, from 1995 some cars could be set for low octane fuel in markets where that's grade was normal, but it certainly performed much worse.

The BMW K1300 is a good example of an engine that was designed to operate well on two different fuel grades - but to function optimally on only one of them - this 4 cyl 175bhp engine revs to 10k rpm. And came before anyone was stupid enough to make ethanol a part of normal petrol.
From the model's European manual (note runs the same engine map software for USA) Recommended fuel grade
98 ROZ/RON (Premium plus unleaded)
95 ROZ/RON (Premium unleaded (fuel grade, usable with power- and consumption-related restrictions))

However - now the change -
ALL current BMW's since we went ethanol infected fuels no longer state the need to use, or that there will be any benefits of using super unleaded high octane fuel

I only just worked out why - because the world has moved on to your theft - rather than your fun and happiness. The vehicle has been set to burn lots of fuel so they can make more money - hence E15 a cheap to make fuel, thus you burn a much higher quantity to give the same energy output. And to ensure you don't get good ideas to use conventional high octane ethanol free fuel, they have deliberately been encouraged to build and thus delivered an engine map that fails to re-optimise its setup to make use of the advantages of the better fuel. So its slower, less responsive and always runs sub-optimally. You have less fun, they sell more petrol....

 

I was at an old world car thing and asking about this last month

the big boys remove the ethanol manually - hard work
the rich boys pay $25 a gallon and get it infection free
the in-betweeners can by a baby 50ml bottle of "stuff" that reduces the aging and separation which should get you through winter but at $10 to treat 50 liters (13 ifffy US Gallons) its still a big money solution

 

Thanks for all the great info BOTUS…had a wonderful drive this afternoon in dad’s old Merc…trying to burn off that ethanol gas before she settles into winter storage. Winter Pirellis and 18” original rims are back on…just in case I get an inkling to take her for a mid winter’s run on a clear day (winter tires are mandated in these parts between November and March). I was surprised how smooth she ran compared to my 19” AMG blades with Michelin AS3+ rubber. These cars a such a pleasure to drive. This petrol/ethanol thing has me a little perturbed though…at least the drive made me feel better! Take care mate!

 

glad you enjoyed the drive

mine on 17" winter tyres was much safer and far smoother riding - summer tyres below 12C or the merest hint of grease on the road and its all over the place - never even noticed it was even a little slippery on the old winter ones, driving much harder

another tip on storing fuel - not sure I like why it works... but they say a FULL tank is better than a empty one - lots of air to suck up on a part filled tank and this tends to age it more
but I wouldn't do ethanol and fill it up - we just had a bod mention his tank rusted through - we didn't even realise the things are steel - of course the water sinks to the bottom exacerbating the risk if there are any rusty areas in there - and the price of a new tank was $1200