My C15's finally succumbed to its fuelling issue - it seems

[van ordinaire]

For years now it's not really been a problem, providing I re-fueled before it was down to a 1/4 tank AND never filled the tank, although a couple of times it's died, as though out of fuel, immediately after refuelling, but priming it solved that problem. (last time was on the way up to Scotland - so that'd be a good 7,000 miles ago.). It pulled a similar stunt a couple of months ago but the issue was complicated by what I thought was a flat battery but turned out to be the starter. New starter, re-charged battery - & it started 1st turn of the key (but still left wondering why it just cut out barely off the forecourt).

Couple of weeks a go the glowplug warning light didn't come on - & it wouldn't start, at least not straight away, but a bit of fiddling did the trick. Inspired guess was the relay: cheap & easy to replace, so that was done, although light was still a bit tizzacky but after a couple of ignition on-off cycles it behaved as it should - & started straight away, as it always has.

That gets us to last weekend: Saturday, refueled, turned the key & pulled away from the island - but never got across the forecourt when, to all intents & purposes, it seemed to have run out - although, of course, it couldn't have. Attempts to start it just flattened the battery (yes, that's got to the still holds a charge but now has little reserve for reluctant starts) so had it recovered. Put battery on charge overnight, replaced it in the morning, turned the key the moment glowplug light went out - & away she went. So, once again the reason for the earlier fail to start remained a mystery. Bumbled around Torbay with no cause for concern &, later, left to drive back up to London, accomplished with no drama or cause for concern until, probably, about a mile from my exit off the M25, it started to lose power, felt like it was missing, but was still clocking 70 as I came down the slip road; that ends at a light controlled roundabout. As I prepared to stop, felt the revs go up a little, a sure sign it's about to run out, so just managed to get off the road before reaching the stop line. Never thought that I might actually just have run out as I'd only done 244 miles since putting in 27ls, so having flattened the battery trying to restart I called my recovery service. While waiting, it did occur to me that if it had been almost empty when I refueled, at 40mpg (which is what it consistently returns) I might just've run out. Anyway, at 10 o' clock on a Sunday night, given where I was, there wasn't going to be any roadside assistance, just straight recovery for the last 10 miles. Monday evening, home from work, empty the 5ls I always carry in the back, refit fully charged battery - but it just won't to know. One thing that was apparent though was that didn't matter how long/hard/often I pumped the primer, it never offered any resistance - so now I'm really struggling because I hate non-starters AND really know nothing about diesels. Last evening, fired with inspiration, whip the top off the filter housing, pull out filter - &, there's about an inch of fuel in the bottom. Nothing for it now, (apart from unpacking new battery which, ironically, I'd ordered Sunday evening), as need more diesel which arrives too late for me to venture out in the cold & dark again. Remembering what a pig getting that clamp on & tight to ensure the top is airtight, up at 1st light to slop in some diesel & refit it. Back out there this evening, 3rd time lucky (?) - nope, still won't prime, so not surprising it won't start, although coughs encouragingly on starter fluid squirted in the intake. So, there we have it, stuck at the end of the drive & I've not the slightest idea where to look/turn next.

[white exec]

Provided there is fuel in the pump (and no air), and the engine stop solenoid on the pump is powered up, the engine should run.

To check the stop solenoid is being supplied, connect a small 12v test lamp to the terminal and Gnd, amd run it into the cabin (or to the scuttle, where you can see it). When the engine cuts out, check whether the solenoid is still getting its power.

Also check for air in fuel. Connect a short length of transparent fuel pipe between fuel filter and pump, and check it for signs of air. The whole fuel line (right back to the tank) is under suction, and air can get drawn in. An air-leak may be affected by temperature (they usually are, annoyingly) so when a hot emgine arrives at a filling station, under-bonnet (and under-car) temperatures can temporarily soar, and cause/aggravate the problem.

The GP light on the dash is controlled by the GP relay, in turn receiving control (not the main GP current, which is direct from Batt+) from the IGN switch. If turning the IGN on and off changes the behaviour of the GP light, suspect the IGN switch, or wiring from it. Haynes (XUD) will habe a decent wiring diagram.

[moizeau]

Last evening, fired with inspiration, whip the top off the filter housing, pull out filter - &, there's about an inch of fuel in the bottom.

This would suggest, the primer or the fuel lines.
Follow Chris' advice regarding the clear pipe between the filter and pump. Have you got the 'poire' primer? These can become porous or get hair line cracks that don't leak. Other than that, it's the tank to primer fuel line. This goes via a 'pre-heater' on the back of the block behind the water pump. Absolute pig to get at, it's supposed to pre-heat the fuel. It can't when cold anyway, so bypass it.
Best of..

[xantia_v6]

It sounds like you have a bad air leak or blockage upstream of the primer, perhaps the strainer in the tank?

I suppose you should be able to test whether the primer is pumping air, or nothing?

[Gibbo2286]

Get yourself a good length of fuel pipe, run it around the outside of the van and down the filler neck into the fuel and connect it to the primer, that will eliminate any problems between the in tank pick up and the primer, if it pumps properly like that then you know you have either a leak or a blockage in the fuel line, if it doesn't then you have a problem at the primer or forward of it at the filter head maybe.

I've seen fuel failures caused by air leaks in the line, sludge in the tank, even in one case the remains of a plastic bag sloshing about in the tank and blocking the pick up, also the blocked tank vent causing a tank to get sucked flat.

Timing of the glow plug can be dodgy on the old C15, the light goes off prematurely but as you've changed the relay that's unlikely, if you hadn't changed that I would have suggested ignoring the light and just counting to 30 when you switch on before turning to start.

[van ordinaire]

Thanks for all your prompt responses but such is my ignorance of all things diesel I'm not sure I fully understand what I'm being told, so please forgive me while I go through your posts, making some observations. However, before that I should mention another episode in the fuelling saga which I forgot yesterday, but which I may have to refer. A couple of Christmases ago driving down to Devon & very close to my destination, it developed a decided reluctance to climb hills which was diagnosed as an injector but turned out to be porous flexible fuel line from the tank. It's since doing that job that a leak if the tank was filled became apparent: suspect pick-up seal - & I vowed I'd never drop the tank again.

Now, (1) stop solenoid: not sure I could identify it, much less find the electrical connection (there's a totally useless piccie in the ZX B-o-L & I doubt the C15 one is any better, besides it's out in the van - & it's cold out there!), even in daylight - but how do I check it if it won't start?
(2) pretty sure problem is air (again!) - but how do I get rid of it? The fuel line from the filter to the pump IS clear or, at least was when it was new BUT if there are no bubbles, how can you tell if it's full of fuel - or air?
(3) I think the GP light may be a bit of a red herring, as after the 1st couple of false starts it's behaved as it should; I only mentioned it because it was part of the very recent history.
(4) The primer is a big rubber button (at least appears to be , although there is clearly more to it than that - & it appears to be an integral part of the filter bowl) with no obvious plumbing.
(5) As I've mentioned, the fuel flexi from the tank is relatively new - but won't be replaced in any circumstances, in any event. I'd quite forgotten about the "pre-heater" but replacing the metal pipe would appear to be impossible any way - although I've not looked at it with a view to removing it.
(6) If there's a leak upstream of the primer, the poor ol' things probably scrap - if the strainer's blocked, it definitely is!
(7) How do you check the primer's pumping at all, never mind what?
(8) The cost of that much fuel pipe would better put towards getting someone round to, at least, diagnose the fault - even washer hose is ridiculously expensive now. Besides (a) for whatever reason you can't get a length of hose down the filler neck, as I discovered when I tried to pump the tank out before removing it - & there may only be a gallon in there (b) there's no obvious way to attach t'other end to the primer. If I can find that, I'll try dropping it into a gallon can.
(9) I did try guessing when the GP light would've gone out, had it come on, without success which suggest it wasn't merely the light not coming on. As I said, I think that's a red herring BUT, if I ever get it going again I doubt I'll be able to resist the temptation to put the old relay back - just out of curiosity.

Anyway, it's too late for replies now, much less going out in the cold & dark to investigate pipe runs & plumbing connections, tomorrow evening I'll be letting the train take the strain, over the weekend I'll be re-acquainting myself with the red Cherokee, which has been away for about 6 weeks having some welding done (it was being done "between jobs" to keep the cost down) so, it'll be Monday before the C15 gets another looking at - unless I decide my time/efforts wouldn't be better spent on the Xantia, which is also out of use pour le moment. Thanks again for your time.

[white exec]

I think you've decided to abandon it, so not much point in embarking on more advice on how to tackle the problem. Perhaps a new home can be found for her.

[moizeau]

Hopefully not. This will be something very simple.
So you have the all in one filter/primer. There is an air bleed at the top. Pump the primer several times, unscrew and retighten the screw and you should hear air or see fuel squirt out, continue until only fuel comes out. Turn the key to the first contact to open to stop solenoid and prime again, leave the air bleed alone now. You should now see fuel flowing from the primer/filter to the pump.
Your set up has the filter before the primer, the 'poire' set up is opposite.
Going back the the previous quote I used, this would suggest you're sucking air.
My first port of call would be the preheater. Follow the inlet to the filter down the back of the block, it goes to the preheater, which is just a water fed heat exchanger encompassed in the cooling system. From there it goes to the tank. Check the two connections and condition of pipe in the area. If poor run a new section from the primer to a good bit before the preheater and bypass it.
If you've tried starting it with no fuel getting through, once you have fuel, you will probably need to crack in injector to assist with the initial start.

[van ordinaire]

I think you've decided to abandon it, so not much point in embarking on more advice on how to tackle the problem. Perhaps a new home can be found for her.

Not at all, but have given up on responding in full, having seen the 1st attempt disappear before my eyes. However, I do draw the line at dropping the tank again.

The problem now is the Xantia's needs are more pressing & not having the use of it is more of a problem - BUT I will need the C15 for Christmas - & Maarstricht only a couple of weeks after.

[van ordinaire]

Hopefully not. This will be something very simple.
Me too, but clearly something I can't see for for looking.
So you have the all in one filter/primer. There is an air bleed at the top. Is there? On a DW8? I will look again on Monday, before (weather permitting) grovelling under the Xantia. Pump the primer several times, unscrew and retighten the screw and you should hear air or see fuel squirt out, continue until only fuel comes out. Turn the key to the first contact to open to stop solenoid and prime again, leave the air bleed alone now. You should now see fuel flowing from the primer/filter to the pump.
Your set up has the filter before the primer, the 'poire' set up is opposite.
Going back the the previous quote I used, this would suggest you're sucking air.
My first port of call would be the preheater. Follow the inlet to the filter down the back of the block, it goes to the preheater, which is just a water fed heat exchanger encompassed in the cooling system. From there it goes to the tank. Check the two connections and condition of pipe in the area. If poor run a new section from the primer - Yet to see any plumbing to the primer, which appears to be an integral part of the filter housing; clearly another more thorough search (& some dismantling) is called for (hampered by doing it in the dark) - a good bit before the preheater and bypass it.
If you've tried starting it with no fuel getting through, once you have fuel, you will probably need to crack in injector to assist with the initial start. Do hope not, as (I recollect) they also difficult to see, much less access, without major disassembly; but let's worry about that, IF I get to that stage.

[van ordinaire]

Well it was too wet to crawl under the Xantia, so had a closer examination under the bonnet of the C15.

Definitely no sign of a bleed screw.

I was wrong about the clear fuel line, it appears to be the supply - to the top of the filter housing, not the primer.

Can't see the plumbing from the filter to the pump, like so much on this engine it's under/behind something else - & it's too wet (& dark, while the work lamps being recharged) to get underneath to try & fathom out how the pipes to/from the tank get into the engine compartment; have that to look forward to tomorrow evening! (who knows, might even find this pre-heater).

Was going to start shopping for what I'll need to get to an injector (as I was minded to replace the glow plugs anyway) but becoming increasingly disheartened & maybe trying to find someone'll who'll do the work for me is a better use of my time.

[van ordinaire]

Just been beaten indoors by the rain, thought I was making some progress - but just fooling myself.

Having removed the trunking between the aircleaner & the EGR valve I think I can see the connection to the bleeder - but to get to it means removing the EGR itself, if not the complete air manifold, which I'm not in a position to do - at least just yet. (more tools & replacement parts required)

But I'm getting ahead of myself, (apart from the "quick release" connectors & the fact I can only shine a light on one part at a time) the real problem is, I just don't understand how this fuel system is plumbed & the pipe runs are such I can't even work out where, e.g. the other end of the pipe to the bottom of the bleeder is or which is the supply & which is the return (I remember having the same problem with the pipes to/from the tank).

[van ordinaire]

So 2020's already off to rubbish start as obviously won't be getting to Maastricht - unless I take the Cherokee, but @ 16mpg that's not really sensible. So can plow what that would have cost into getting the C15 going - except it's going to cost anything up to £150 for someone to come out, tell me what's wrong & quote me for fixing it i.e. well into the cost of another one. BUT I have become quite attached to the (not so) old thing AND I don't like being beaten. I'm even coming round to dropping the tank - if I really have to - & while the ply lining is still detached & as it's probably only got a couple of gallons in it I suppose it won't be quite such chore; although doing it out in the road again doesn't much appeal.

Still not been under it to look for this pre-heater - saving that for New Year's Day now.

I have now re-read this whole thread & really am none the wiser because I just can't see how to implement the advice offered; perhaps I just don't understand the advice any more than I understand the fuel system.

If, as I believe, the fuel enters the filter at the top & exits via the primer to the pump, with the filter bowl full how can the primer deliver air to the pump? Tempted to crack the inlet to the pump & try priming it, but afraid of making matters worse - if that's possible.

[xantia_v6]

Can you jury-rig a (small) temporary tank under the bonnet to localise the problem a little?

[van ordinaire]

Probably not under the bonnet, but previously I did have a 5l container under the van with a piece of hose dropped into it, that eliminated the tank, pick-up & flexi to where I'd disconnected it, it started, ticked-over & revved with no signs of bubbles under the bonnet; that was to prove the failed injector diagnosis was wrong & the problem was at the back (replacing the 2 flexis from/to the tank cured the problem). Tried something similar this time, using an electric pump to draw fuel directly into the filter bowl - but it made no difference.