Diesel fuel filling problem

[darfash]

Hi all, wonder if anyone has thoughts on this problem:

 

Yesterday we topped up our Yeti (diesel 4x4 dsg) to make a journey just short of 100 miles return trip. Today we wanted to get a real mpg reading my topping up again, but it would only take 4.4 litres. So we drove another 10 miles to another garage to see if we could top up again. When I got out of the car the diesel had leaked out from the fuel cap all down the car and we only managed to get another £1 of fuel in the tank. Before we filled up the first time the fuel guage was reading 2 bars down from full, but after the first attempt to fill up it was reading only three quarters full and is now only showing that is what is in the tank.

Your thoughts would be appreciated, car is booked into garage next week. Is this a costly repair?

 

Thanks in advance

Darfash

 

[Llanigraham]

What repair?

From that report I see no possible "fault" with the car, and behaviour that is normal, other than you overfilling it.

The 4x4 has a "saddle" tank that is split either side of the rear prop shaft so it takes a while for the levels to equalise. When you fill the tank you are only filling one side to start with, until that equilisation takes place. It isn't instant.

[darfash]

Thanks for the prompt reply.

That sounds reasonable but why would the fuel tank show less than what was in the tank before attempting to fill in up? In the recent pass (only had it 3 months) when filling up from a quarter full the whole tank was filled in one go and I didn't go pass the first click of the pump today.

 

 

[Lyminton]

There is a suction pump which should send fuel to the other side of the tank. It may be worth to check if it's still working....

Edited 12 April, 2017 by Lyminton

[darfash]

Hi

I'm no mechanic and I'm also disabled so can't crawl underneath to check anything like that, I still don't understand why the fuel gauge would read less after attempting to fill the car. Still think it is the best car I've ever had.

 

[Llanigraham]

Because the sender unit is in one half of the tank and if the fuel isn't transferring across, such as if the car is on a slope, that's what can happen. 

It isn't a fault but one of the things that can happen with a saddle type tank. You soon get used to it.

[Ootohere]

darfash, i put maybe 30 litres in at Tesco in Scone and brim the tank of my SEAT TDI then travel to Dyce so 85 miles and the fuel does not show as full.

I then go to Sainsburys at Bridge of Dee and Brim it again before heading south and it then shows full usually & that is 2 hours after the last brimming.

Same thing has happened now 3 times when filling at Scone but at no other filling station.

 

Edited 12 April, 2017 by Awayoffski

[gumdrop]

I fill mine and watch the money, while gently nudging the car to make it rock,

this seems to do a good job of filling to the brim. If you know how much the

tank holds you can price half a tank = so many pounds for so many litres

thats why I watch the money I generally use about £37

[Frenchtone]

^ ^ spooky!!

[Ootohere]

If a full tank was going to cost £74 to fill that is a very big tank in a Yeti or very expensive fuel.

[skoda1982]

if i brim the tank i normally get 65/75 mpg before the needle moves so i think about 4 to 6 lts in the filler pipe and expansion tank. cost £55 from warning fuel light on to brim last week

 

[ernieb]

I've found that it's important to fill the tank slowly and don't fill until the tank is at least only half full.  I've not had any issue filling any of my three Diesel Yeti, no backflush or leakage.

[bigjohn]

You shouold never brim a tank on filling as :-

>At best you may loose some fuel especially as it expands in the tank and has nowhere to go

>At worst you may cause damage, throw engine light (In the petrol you can saturate the charcoal canister - I did this, ONCE)

 

It's best to fill to the first click (Occasionaly if you have mis inserted the filler spout this may be premature and petrol station pumps vary) - if you use a site such as Spritmonitor https://www.spritmonitor.de/en/ or http://www.fuelly.com/ you can eventually work out an accurate "average mpg" as an under read one time will haver an over read the next time

 

See my signature below or follow https://www.spritmonitor.de/en/detail/720963.html for mine - you can spot some seesaw figures where pumps (or my driving!)  vary. Whilst at home I try to use the same pump at a nearby Tesco (Greenenergy 99 Ron petrol)

[Ootohere]

Brimming is not always the same as Venting. 

[skoda1982]

I don't think diesel expands petrol does

 

[philbes]

3 minutes ago, skoda1982 said:

I don't think diesel expands petrol does

 

Diesel expands less than petrol.

[Ootohere]

Very much so & fumes are so very different.

You can have a bucket of diesel and extinguish your cigarettes in it without flames.

(Best not try the same with Gasoline / Petroleum.)

Which is just as well that Diesel Fuels (Heavy Oil) are different when you might see diesel in the hull of boats sloshing about on the water.

 

But what ever you still need to take care and no the system you have, and think about safety and not Brimming or Venting if then parking up without using up a good bit of fuel.

Edited 14 April, 2017 by Awayoffski

[darfash]

Hi

 

Thought I keep this topic up-to-date:

 

Waited till the fuel tank was showing just over half full and topped up - no problem - will keep an eye on things from now on - local Skoda garage (independent) said they had not heard of this problem before.

 

Thanks for all the replies.

Darfash