Good old foaming at the mouth Derv

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Sat 7 Feb 2009 07:53
Good old foaming at the mouth Derv - oilrag
The usual Shell filling station was full - so went across the road to BP. The hoses are now black and the allegedly confusing label removed from the pump handle. (actually the top surface of the plastic `advertising surface` on the handle was missing - so not sure about that)

Seeming to foam in the filler neck like a rabid dog - kept adding another litre as the foam receded and advanced - up and down the filler neck. Eventually putting half a litre down the body work - can`t remember when I last did that.
I last saw this years ago using supermarket Derv and perhaps have been spoilt by exclusively using Shell none foaming fuel which gives a clear fuel `surface` in the filler neck.

So what`s the score on foaming - for those who fill up with differing brands - perhaps this was a one off?

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Sat 7 Feb 2009 09:17
Good old foaming at the mouth Derv - jc2
I've filled up with same brands and found them sometimes to foam(in varying amounts) or not foam at all.Took it up with a fuels specialist and was told that it would be varying amounts of anti-foam additive.
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Sat 7 Feb 2009 09:37
Good old foaming at the mouth Derv - Harleyman
I wonder if different pump delivery rates have something to do with it?
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Sat 7 Feb 2009 09:41
Good old foaming at the mouth Derv - gordonbennet
Thats an unusual amount of foam OR, we have our own fuel tanks for the trucks but use BP if needed, haven't really noticed any significant foaming for a number of years.

I wonder if the anti waxing additive might have been increased slightly to explain the excess foam?

Don't really get splashbacks in either trucks or our pick up, but then the filler necks are so short on both unlike the 3' or more on most cars.
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Sat 7 Feb 2009 10:44
Good old foaming at the mouth Derv - Hamsafar
They add silicone to stop foaming. Maybe it was missed out or the delivery was made from some other oil co.'s depot and was incorrectly specified.
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Sat 7 Feb 2009 10:59
Good old foaming at the mouth Derv - Old Navy
They add silicone to stop foaming. Maybe it was missed out>>


I hope it was not put into petrol instead, I believe there was a problem with this recently. My diesel top ups have been OK. All our local diesel comes from the Grangemouth refinery, suitably doctored by distributors.

Edited by Old Navy on 07/02/2009 at 11:01

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Sat 7 Feb 2009 11:03
Good old foaming at the mouth Derv - Andrew-T
Silicone - are you certain? What happens to the silica produced in combustion?
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Sat 7 Feb 2009 11:18
Good old foaming at the mouth Derv - Altea Ego
Not had a foaming issue for years. Mostly on Tesco, but not encountered it on any other either.
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Sat 7 Feb 2009 11:53
Good old foaming at the mouth Derv - Hamsafar
"Silicone - are you certain? What happens to the silica produced in combustion?"

Yes, I am certain,
en.wikipedia.org/wiki/Siloxane
It's also in cheap liquid-oil fried food too!
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Sat 7 Feb 2009 12:13
Good old foaming at the mouth Derv - Manatee
Silicone was implicated in the supermarket fuel incidents. Diesel anti-foam was added to petrol by mistake. The result was in effect a coating of glass on the oxygen sensors of the affected cars.
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Sat 7 Feb 2009 13:02
Good old foaming at the mouth Derv - Hamsafar
Andrew, here is a patent for Siloxane used as a fuel antifoam.
www.freepatentsonline.com/EP0891406.html
here is another about it's use in engine oil
www.patentstorm.us/patents/6221815.html

I have also found many references with google about how it can become Silicon Dioxide/Silica (an abrasive white powder) and damage engines, turbines, turbochargers and O2 sensors. So if the fuel foams up, maybe that's a GOOD sign!

Edited by Hamsafar on 07/02/2009 at 13:03

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Sun 8 Feb 2009 05:59
Good old foaming at the mouth Derv - oilrag
Wonder if silicone has gone into petrol then? Or can filling stations managers (are they franchised?) order a tanker full of `cheapo` amongst all the additived regular fuel - to make a fast buck?

(Wasn`t a filling station on the upper A1 caught doing that around 12 years ago)

Anyway, It wasn`t the fill rate as the Mk2`s filler neck seems really restrictive - if you don`t want repeated cut off - you have to insert the nozzle only about four inches and literally pour it steadily in.

Incidentally, went out East to Bridlington yesterday - no snow or indeed salt on the roads - returned home and fueled the van at the usual Shell place and no foam at all.
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