Ran out of fuel - when tank 1/2-full!?

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Re: Ran out of fuel - when tank 1/2-full!?

Post by white exec » 01 Oct 2018, 16:19

Gibbo2286 wrote:
01 Oct 2018, 16:17
One thing just occurred to me, does that vehicle have up and down hoses i.e. a return hose to the tank?
I had a job once where they'd been replaced by the owner and he'd got them mixed up and had the return hose on the wrong connector, it would only lift fuel from part way down the tank where it ended.

Well, there's a thought. #-o

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Re: Ran out of fuel - when tank 1/2-full!?

Post by van ordinaire » 01 Oct 2018, 20:52

Gibbo,

Yes it does, but they're different sizes so difficult to mix up - but even if I had made that mistake, it wouldn't take 3,000 miles to show up.

Chris,

You've lost me, I can hardly do that at the very moment it seems to run out of fuel - even if it conveniently does it while parked, as it's unlikely to be somewhere I can work on it. In any event, I can't see how that would be any different from emptying the can into the tank.

Further update: got back from work while some daylight left, so went out & ducked under the van (surprised I could do that, especially parked as it is straddling a speedbump - oh the joys of living in an inner London suburb!). (a) must be on the point of running out, as, maybe, 250 miles on, it's probably registering 1/2-full but bottom of tank is perfectly flat (b) seems I can look for the leak next time I fill it up (c) outside of tank is still very wet - a new development - & there's a droplet formed on the clip for one of the fuel lines, suggesting fuel is running down the outside of the hose - but, from where? (& has it really been hanging there for best part of a day?)

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Re: Ran out of fuel - when tank 1/2-full!?

Post by white exec » 01 Oct 2018, 22:20

If that droplet of fuel is leaking from the pipe that goes to the filter, then the same leak/hole could be letting air into the line when the engine is running (and the pipe is under suction). This shouldn't be happening.
Why it only cuts out with a half-full tank I don't know.

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Re: Ran out of fuel - when tank 1/2-full!?

Post by jsp » 02 Oct 2018, 02:42

Is your fuel guage leveller not shorting out on earth? I had similar unit and shorted out on 1/2 and stays there. Pulled a new wire and problem gone.

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Re: Ran out of fuel - when tank 1/2-full!?

Post by van ordinaire » 02 Oct 2018, 19:50

I think we can discount a gauge fault, as it "runs out" after 230 - 250 miles which, at 40-odd mpg is about 1/2 a tank - & it only takes 20 - 25 litres to fill it up, i.e. it is about 1/2 full.

That fuel weep is a new thing which will need a closer look - when I've got more time, more light (in terms of brightness and duration) & better access. However, I did start it up this evening & carefully examined the clear plastic pipe from the filter housing to the pump &, just as I expected, no bubbles! I then had a look under the tank with it running for any telltale signs. Must confess I couldn't identify what I described yesterday; did find about 2" of rubber pipe that was damp on the underside, which might suggest a pinhole or porosity, but I dried it off - & it stayed dry.

I think, having provided as much history of fuel issues, which I thought might mean something to those who know far more about such things than I,we have conflated 2 issues. I had no reason to believe there was an air leak problem now, it's just that whatever I did to cure that particular problem at the tail-end of last year, perhaps coincidentally, cured the earlier premature running-out issue; it is just that which has returned, but this time, at an even higher fuel level.

Sooooh, where does that leave us? Please don't say "taking the tank out" because that just isn't going to happen!

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Re: Ran out of fuel - when tank 1/2-full!?

Post by white exec » 02 Oct 2018, 20:22

Remind me, what was the result of attempting to drive a full tank with the tank filler cap removed?

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Re: Ran out of fuel - when tank 1/2-full!?

Post by van ordinaire » 02 Oct 2018, 23:46

white exec wrote:
02 Oct 2018, 20:22
Remind me, what was the result of attempting to drive a full tank with the tank filler cap removed?


Not tried that yet (1) I have to investigate how to remove the safety strap from the cap
(2) Have to plan it so, if needs be, I'm within striking distance of reasonably priced diesel, i.e. not somewhere between London & Devon, at night. Perhaps this weekend in Belgium, off A-routes, might be a good bet.

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Re: Ran out of fuel - when tank 1/2-full!?

Post by van ordinaire » 09 Oct 2018, 21:24

It took about 9 months to do the 3,000 miles to come up to the 180,000 mile oil & filter change - & the next oil change is due already: that's 4 -500 mile round trips for 5 consecutive weekends for you!

That aside, not much further forward. Having driven up from Devon, via a very circuitous diversion, was approaching the critical 240 miles/1/2-tank & didn't relish running-out on the way to Dover for the 2:00 am ferry - or trying to board with no filler cap! Took on a couple of gallons before setting off - & filled up in Dunkerque, didn't replace the cap & set off for Malmedy. However, that only 199 miles, & the gauge wasn't down to 1/2. Good run, cracking pace, no issues. Setting off for the return Sunday evening decided I'd refuel on route so after another 48 miles, with the needle hovering above 1/2, I spotted the cheapest diesel I'd seen on this trip; took 26 litres, more than I was expecting BUT also more than on the occasions when it's "run-out". Also, a quick check underneath revealed no leak - but there were signs of spillage along the side. THAT might explain the apparent poor consumption; perhaps the Ardenne is not ideal territory for running without a (fairly low, vertical) fuel cap!?

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Re: Ran out of fuel - when tank 1/2-full!?

Post by white exec » 09 Oct 2018, 21:47

So, after all that, we still don't know whether removing the cap has any effect on using the last half tank?
C'mon, pluck up the courage, and Just Do It.

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Re: Ran out of fuel - when tank 1/2-full!?

Post by Michel » 09 Oct 2018, 23:06

van ordinaire wrote:
02 Oct 2018, 19:50
I think we can discount a gauge fault, as it "runs out" after 230 - 250 miles which, at 40-odd mpg is about 1/2 a tank - & it only takes 20 - 25 litres to fill it up, i.e. it is about 1/2 full.

That fuel weep is a new thing which will need a closer look - when I've got more time, more light (in terms of brightness and duration) & better access. However, I did start it up this evening & carefully examined the clear plastic pipe from the filter housing to the pump &, just as I expected, no bubbles! I then had a look under the tank with it running for any telltale signs. Must confess I couldn't identify what I described yesterday; did find about 2" of rubber pipe that was damp on the underside, which might suggest a pinhole or porosity, but I dried it off - & it stayed dry.

I think, having provided as much history of fuel issues, which I thought might mean something to those who know far more about such things than I,we have conflated 2 issues. I had no reason to believe there was an air leak problem now, it's just that whatever I did to cure that particular problem at the tail-end of last year, perhaps coincidentally, cured the earlier premature running-out issue; it is just that which has returned, but this time, at an even higher fuel level.

Sooooh, where does that leave us? Please don't say "taking the tank out" because that just isn't going to happen!


Sorry, where's the fun in that?

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Re: Ran out of fuel - when tank 1/2-full!?

Post by van ordinaire » 10 Oct 2018, 22:30

Touché :)

BUT, it was cheap as chips &, in 4 years/30,000-odd miles has only really let me down once (when the clutch went!). This is not really even an irritation or inconvenience, now I know how to avoid running out, only a puzzle & while I could effortlessly cruise across Europe in the Eldorado - the C15 IS just so much fun!

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Re: Ran out of fuel - when tank 1/2-full!?

Post by van ordinaire » 10 Oct 2018, 22:53

white exec wrote:
09 Oct 2018, 21:47
So, after all that, we still don't know whether removing the cap has any effect on using the last half tank?
C'mon, pluck up the courage, and Just Do It.


No, only a suggestion that it might.

It's not a matter of courage, but exercising reasonable caution. Sorry, but the prospect of running out somewhere on the A303 (or worse the M5) at night, after a day's work just doesn't appeal (especially as, on past form, I'll only get about 20 miles on the spare 5 litres, if I do have to add that). I will have to work it so, at around 230 miles from full, I'm just mimsing around locally.

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Re: Ran out of fuel - when tank 1/2-full!?

Post by van ordinaire » 13 Oct 2018, 19:00

& so it was to be. Thanks to (another!) diversion I'd done 250 miles getting to Torbay last night [fortunately for my stress level, due to the failed bulb(s) in the dash,I didn't know that 'til this morning]. Before even starting the engine, therefore, I removed the filler cap & after only a couple of miles ran out. I did try priming it before adding any fuel, as I recall someone suggesting but that didn't do anything. Added the spare 5 litres &, after the usual performance, was good to go. Put another tenner's worth at Morrison's while I was in Paignton - & the gauge is reading well over 3/4's, so it was nothing like empty when I "ran out" - as I would expect after that distance.

So where am I now, apart from refueling every 230 miles?

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Re: Ran out of fuel - when tank 1/2-full!?

Post by Gibbo2286 » 14 Oct 2018, 10:13

I'd guess it's time to 'bite the bullet' start at the tank pick up pipe i.e. lift out the sender unit and make sure the pipe reaches to the correct depth and no holes/damage part way up.

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Re: Ran out of fuel - when tank 1/2-full!?

Post by Peter.N. » 14 Oct 2018, 10:36

I have had a similar effect with a C5 and a 406, both were showing fuel but actually ran out. A BSI reset cured both of them, not the same problem I know but it can happen.

The most memorable occasion was back in the '70's when I was towing a caravan in Scotland with a PC Cresta fitted with a Perkins 4/108 engine, it stopped at Lochernhead although the gauge was reading a quarter full, I found a house with a phone and called the AA, waited for hours, a huge American looking tow truck eventually arrived, much to the delight of our young son, and took us to a garage that was only about a mile away, I would have walked if I had known it was there.

The reason for this problem? there was a big dent in the bottom of the tank.

Peter