Alkylate petrol for outboards?

[chewi]

My info about BP Ultimate was in response to a number of queries to the Oil companies last summer.
Only BP specifically declared on 27/9/2013 that their BP ultimate was ethanol free. All others confirmed that even their top grades contained ethanol.


Dear xxxxx,
There is no ethanol at all in our BP Ultimate fuel which can be found at every BP garage.
Kind regards,
Anita

Retail Customer Care Team
Email: careline@bp.com
Telephone: 0800 402402
Fax: 0845 082 1706
Internet: www.bp.com

 

[Bru]

I haven't had confirmation one way or t'other to my query, just a holding reply

 

[jdc]

Conclusive results!

I started this thread, and promised to try the above mentioned super expensive (£18 a gallon) pre-mixed 2-stroke petrol.

I'm pleased to report that the experiment proved conclusive, and you SHOULD ESCHEW THIS MUCK!

I used the pre-mixed 50:1 two stroke blend. I know that outboards should use special outboard 2-stroke oil, but for the one or two pints of fuel I use in a year in my tiny Mercury 3.3 assumed it would make little odds. I was wrong.

On the plus side, when I stripped down the engine the carburetor was very clean, with no gummy residues at all, which hadn't been the case beforehand so it does dissolve old stale petrol. But there's a clue in the phrase 'stripped down the engine'!

I topped up the tank with a about a pint of the new fuel, I suppose diluting the old petrol about 1/3 of the old 50:1 mix and 2/3 the new alkylate fully-synthetic stuff. No problem, it ran slightly better I think.

A couple of months later we ran out of petrol and I re-filled with the 50:1 alkylate two stroke stuff, hence from this point it was using only the fully synthetic fuel and oil. After about 1 minute of motoring, seemingly almost straight away in fact, there was a terrible and terminal sounding bang and the engine stopped dead. It would re-start, but was completely gutless and would stall as soon as it was put in gear.

We finished our summer cruise and I brought the outboard home and yesterday stripped it down. The piston ring had fractured! It seems that this fuel has no lubricity at all. A new piston ring, new gasket set, new oil seals and new Woodruffe key for the flywheel (the old one had sheared!!) were all fitted this morning and the outboard is running sweetly again.

In all, about a £100 lesson learnt (£18 for the useless fuel, £82 to repair the damage it caused). Ho hum...

 

[vyv_cox]

Fascinating tale, thanks for posting. For the sake of my understanding, would it be possible to post close-up photos of the rings, please? If the lubricant is the problem i would expect them to be scuffed, whereas just a fracture with no scuffing would suggest pre-ignition of the fuel.

 

[Giblets]

How very sad. I was hoping this new wonder fuel may have been an answer to Dylan's Seagull aversion!!!

 

[jdc]

...would it be possible to post close-up photos of the rings, please? ...

They're not very good I'm afraid, but here are a couple:


The last few mm of the ring has disappeared (never found it, presumably spat out of the exhaust). The ring is quite scored as well as broken.

PS: I'd quite happily post the ring to you (or leave it at Limehouse - I'll be there on Tuesday - for you to collect sometime).

 

[vyv_cox]

They're not very good I'm afraid, but here are a couple:
View attachment 45199View attachment 45200

The last few mm of the ring has disappeared (never found it, presumably spat out of the exhaust). The ring is quite scored as well as broken.

PS: I'd quite happily post the ring to you (or leave it at Limehouse - I'll be there on Tuesday - for you to collect sometime).

That's very good of you although it is likely to be some time before I am at Limehouse. Will PM you.

Your second pic shows a good deal of scuffing, which supports your diagnosis of lubricant failure. Difficult to understand why an outboard would need a different oil from any other type of engine, I just use the best grade available in mine, in garden equipment and outboards.

 

[Davegriff]

Difficult to understand why an outboard would need a different oil from any other type of engine

Presumably because TC-W3 has a lower ash content residue than other oils, so reputedly keeping exhausts cleaner, though I agree that all two strokes would probably benefit.

 

[vyv_cox]

Presumably because TC-W3 has a lower ash content residue than other oils, so reputedly keeping exhausts cleaner, though I agree that all two strokes would probably benefit.

I think you are right, but if the cause of the problem was scuffing due to poor boundary lubrication then I would have expected any decent two-stroke oil to be formulated to avoid it.

 

[Storyline]

There was a post on here fairly recently (which I cannot find) which mentioned an additive you can use in 2 stroke o/b's to help mitigate the effects of ethanol in modern petrol. Anyone any idea what it was and is any additive worth using ?

For the first time I noticed poor running due to modern petrol when I mixed a small qty of one year (could have been two) old petrol in my Tohatsu 2 stroke. Seemed to fire quite 'lumpily' but it could have been my imagination. Have just put the o/b into the store for the winter and also for the first time syphoned out this years fuel (and ran carb dry).

As we use only 5-10 litres a year I would be tempted by a more expensive fuel designed for o/b use. This could be a modest commercial opportunity for a blender/refiner but I suppose as you cannot store petrol indoors as you can lubricating oils it would be difficult to distribute and sell.

 

[Storyline]

.....
Most pump petrol in the UK will contain some bio-ethanol nowadays there is an EU requirement that 5% of road fuel comes from renewable sources, and this is increasing soon to 10%. If you look on some pumps it says you are getting E95 which means 95% petrol, 5% ethanol. Some pumps now deliver E85.

Given that it is a legal requirement that fuel has to contain some content from renewables it seems possible that Anita @ BP is being economic with the truth (or poorly informed). Think I will also email them and maybe others could also as if it is true there could be a marketing opportunity for them - cue queues of people at the Ultimate pump with their jerry cans.

 

[JoCarr]

Sorry to hear about the issue, was the Aspen fuel the 'old' Aspen 2 or the Aspen 2 FRT which is specifically made for water cooled outboards? Reason for question is I am considering the Aspen 2 FRT for my Mercury 4hp two stroke.

 

[Bru]

Given that it is a legal requirement that fuel has to contain some content from renewables it seems possible that Anita @ BP is being economic with the truth (or poorly informed). Think I will also email them and maybe others could also as if it is true there could be a marketing opportunity for them - cue queues of people at the Ultimate pump with their jerry cans.

Anita @ BP wasn't being economic with the truth - the legal requirement doesn't say that every drop of fuel sold has to contain bio, only that a specified percentage of total fuel volume sold must be bio

So Ultimate, V-Power etc frequently don't contain bio because enough bio is being included n other products to meet the target

 

[jwilson]

My local outboard dealer/repairer puts a few drops of "fuel conditioner" in each canful or tankful of fuel, says it lets petrol last longer and gum up carbs less. I now have a bottle of the stuff (not here- can't remember brand). Since using it I seem to have a bit less gunge in carbs. I do try to run engines dry when possible but you still get some fuel left in carb, and tiny carbs don't need much goo in them to affect running.

 

[rotrax]

I use "Motorex "a Swiss-IIRC- brand of fuel conditioner. I use it because it works, and I still have half a case left over from my Motorcycle business.

I recomended our Classic and Vintage bike owners used it when laying up their bikes for the winter.

It is also a good idea to turn the fuel off and run the outboard untill it stops, and then drain the carb. bowl before putting it away.