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D2 - Fuel and Exhausts Everything to do with getting fuel into the engine, and fumes back out again

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Old 11th November 2020, 08:31 PM
MikkiJayne MikkiJayne is offline
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Default Can't fill the tank - 80 litres max

Hi all,

I'm having an odd problem with Big Red in that I can't fill the tank completely. The pump clicks off at 80 litres, or 1 mark off full on the gauge. I've compared the resistance of the level senders at empty and full with the values shown in Elsawin and everything is correct there so this is a physical issue, not an electrical one, and logically has to be a tank venting problem of some sort. Poking the pip in the filler neck has no discernable effect. The fuel pump is behaving impeccably and will go from 80 litres to 10 with no issues.

Has anyone seen anything like this before? I can't find any similar issue documented on this or other forums so just throwing it out for comment before I start taking things apart.

This is the most I can get in the tank:



This is a new problem since she was in storage for a while.
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Old 11th November 2020, 09:06 PM
HPsauce HPsauce is offline
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Have you tried topping it up very slowly from a can to see if you can trickle any more in? I'd do that first to be 100% sure it's not actually full.

The other thing that springs to mind is some sort of airlock on the venting as you've suggested. And given the recent posts about fuel pump seating and IIRC that the filler pipe goes into that special chamber to prime the pump system, that's where my suspicions would start. But I don't know enough about the details of all that to speculate further.

Finally, how about a spirited drive with some lateral G...
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2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!)
Finally: gone, but not forgotten.....
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Last edited by HPsauce; 11th November 2020 at 09:10 PM.
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Old 11th November 2020, 09:55 PM
MikkiJayne MikkiJayne is offline
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Mmm good idea. I can park it on a slope at the workshop with the filler neck being the highest point and then see if I can get another couple of gallons in. I'll give that a try and see what the gauge says
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Old 11th November 2020, 10:05 PM
HPsauce HPsauce is offline
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And give it a bit of a vigorous rock from side to side, listening for gurgling.
Mostly made in Dartmouth.....
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2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!)
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.

Last edited by HPsauce; 11th November 2020 at 10:07 PM.
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Old 12th November 2020, 01:09 AM
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steamship steamship is offline
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Have you considered the activated charcoal container (1 in image) being blocked?
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Old 12th November 2020, 08:19 AM
MikkiJayne MikkiJayne is offline
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Its certainly concievable it could be that. What I think is happening is that one or more of the tank vent lines (6-9 in that pic) are unable to vent and so the tank fills to the level of the filler neck leaving a large air pocket in the top of it. Its not clear from the diagrams where those lines go, but I think they go in to the large assembly behind the filler neck first, which then has a single line (4) over to the charcoal container. In theory the only open point is 5 which is right on top of the tank.

I won't mind too much if its the charcoal container which is blocked as thats relatively easy to change. I will be a little grumpy if its the thing behind the filler neck as that has pipes everywhere and many rusty fittings. However, I shall be very pleased if its either of those compared to having to swap the whole tank!

I took all this stuff out of Sergey's car relatively intact so I need to get that off the shelf and see how everything goes together.

Its been pointed nose-down overnight so I'll nip up to the workshop (vigorously!) in a bit and see if I can get an extra couple of gallons in there. If so, that would suggest its a partial blockage somewhere which just can't vent as fast as a petrol pump can put fuel in.
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Old 12th November 2020, 03:35 PM
MikkiJayne MikkiJayne is offline
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Definitely a venting issue. I parked on a slope at the front of the workshop with the filler neck corner highest and was able to get another 2 gallons in, with the gauge now showing full.

The first gallon went in no problem, but the second took ages as the neck of the fuel can would get submerged in fuel in the filler neck and airlock itself. It waited until the level dropped a bit, got a gulp of air and let some more fuel out, and carried on like that for several minutes.

Following that there was a prolonged gurgling from the tank as the level settled. Pressing the vent in the filler neck changed the gurgling but didn't stop it.

Need to investigate the venting system...
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Old 12th November 2020, 04:42 PM
HPsauce HPsauce is offline
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The mystery would be what could be partly blocking the system and how did it get there?
And would filling the tank completely, as you have done, then letting the level drop, dislodge, free or open it up?
Sounds like an excuse for more spirited driving...…..

It also seems more likely that it's the central upper breather that is the problem.
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2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!)
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.

Last edited by HPsauce; 12th November 2020 at 04:46 PM.
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Old 12th November 2020, 05:25 PM
HPsauce HPsauce is offline
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Quote:
Originally Posted by MikkiJayne View Post
Its certainly concievable it could be that. What I think is happening is that one or more of the tank vent lines (6-9 in that pic) are unable to vent and so the tank fills to the level of the filler neck leaving a large air pocket in the top of it. Its not clear from the diagrams where those lines go, but I think they go in to the large assembly behind the filler neck first, which then has a single line (4) over to the charcoal container. In theory the only open point is 5 which is right on top of the tank.
How accessible is the charcoal container? Is it possible to disconnect its combined input from the tank vents (4 in the diagram) and see if it then fills normally (just the last 2 gallons from a can)?
That would narrow it down to the charcoal canister or plumbing.

By the way what is line 3? Is that a vent from somewhere else in the fuel system?
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2003 D2 FL S8. Irish Green Pearl/Beige. Solar sunroof, auto-dim mirrors, electric rear seat functions, ski hatch retrofit; extended leather. Aftermarket DVB-T, reversing camera and full XCarlink (Bluetooth etc.).
2016 Volvo V40 T5 Cross Country (4WD) with ALL the toys including adaptive cruise etc. etc. Osmium Grey with Blonde/Charcoal leather interior. Polestar performance "optimisation". (A much rarer model than a D2 S8 by the way!)
Finally: gone, but not forgotten.....
1998 D2 PF S8. AgateGrey/Platinum. Every option (I think) except electric rear seats, tiptronic steering wheel, ski hatch, towbar & dimming door mirrors.
e.g. Cruise control, NavPlus/TV, Bose, GSM, Xenons, Solar roof, Parking sensors, Alcantara/leather everywhere of course. (internal dimming mirror added later)
1998 (very early) Ford Focus 1.8 Zetec; ABS/TCS, Heated screen/mirrors, Aircon, Auto-dim mirror, Leather, Trip computer, Cruise control, OEM Ford SatNav with CD changer.
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Old 12th November 2020, 05:36 PM
MikkiJayne MikkiJayne is offline
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Line 3 goes to the front to the N80 evap valve.

The charcoal can is equally as vexing to get to than the 'expansion chamber' on the other side (which is what Elsawin calls the big lump all the vent pipes feed in to). Arch liner out, then a bunch of hose clamps, although all stainless rather than the sad rusty lumps on the other side. Although, I had the left side arch liner out when I repaired the sill so that's like to come apart more easily than the right side.

It could be disconnected from either side tbh. I might try that before I get out the parts cannon
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