Foamy Diesel

[Op-Ivy]

When filling up I only get 40ish litres in. If I wait another minute for the foam to go down I get another 10 in. When pumping some into a jerry can I notice that before it is even half full it has foamed up to the top. It started doing this back early October...

Has anyone else noticed that the diesel at gas stations lately has been extra foamy? Maybe this has to do with the winter diesel?




Matt

[burn_your_money]

I've found that it's always been really foamy. If I take my time I can usually add another 3-5L to my tank

[andybnwc]

I know in the uk some fuel companys put detergents in the fuel so this maybe why

[Jetta Fan]

Furnace oil is the same way...mind you, it's just #2 diesel with dye and a lot less tax.  :lol:

But I have noticed the diesel is a bit more foamy lately. At some stations with a slower pump, I can get more in before it kicks out and then can't squeeze in as much after waiting as I can at a station with a faster pump. I wonder if it has anything to do with the ULSD garbage they are selling us?

[Vanagoner]

100% biodiesel= 0% foam

even a blend knocks the foam down considerably.
maybe the oil companies have struck a deal with procter & gamble javascript:emoticon(':)')

[rabbitman]

yeah, I can slowly fit in two more gallons after the pump shuts off, a real pain when it's -20F out. I've noticed some fuel is worse than others.

[Op-Ivy]

That's interesting.  That would mean that the rate of flow at the pump and the foaming action of the fuel has a significant impact on the point the pump shuts off.  I've always filled up until the first automatic click-off assuming the amount in the tank was consistent in order to gauge fuel economy.  Foam has been screwing with my calculations?  Dang...

Andrew

Yea... I thought about that a while ago too. Disappointing to not have an accurate way to calculate "smilage". If someone has a good way, then I'm all ears.




Matt

[bigblockchev]

There is a little button nub inside the filler neck which allows the tank vent open and vent off trapped air in the tank. This allows you to fill the tank completely up and get more accurate levels when calculating fuel mileage. You have to push it down with your finger or the fuel nozzle and listen for the air whooshing out as well as watch the fuel drop down the filler neck. I fill up in my sloped driveway all the time so I have to do this or get inaccurate results. It is on MK2 & MK3 at the least that I know of. Cheers Dan

[Turbinepowered]

Yea... I thought about that a while ago too. Disappointing to not have an accurate way to calculate "smilage". If someone has a good way, then I'm all ears.

Whenever I fill up the bus, I always fill it to the same mark on the filler neck. Of course, the filler necks on those are also nearly two and a half inches in diameter, so it's pretty easy to see inside them.

[rabbitman]

I've heard rabbits don't have the button inside the neck so there's nothing you can do to speed it up. I always fill mine right to the top of the neck and it seems consistent enough.

[Jetta Fan]

For a more accurate mileage calculation, do it over sevral tanks of fuel (say 10). This way, the little fluctuation caused by the foaming fuel will not be such an impact.