A couple of weeks before our trip round Europe to celebrate our golden wadding (poor cow!I decided to fix my under reading fuel gauge by fitting a new sender. All went well and the plumbing was refitted as per the Bentley manual and apart from the whole caboosh getting hidden from sight as the tank is brought up into its final position I thought I had done a good job.
Topping up on a cold morning which developed into a scorcher however, a smell of petrol wafted from under the van periodically. So after a couple of careful filling sessions and reassurance from ny braver wife we put it down to a fierce pump and the fact that petrol has a significant temperature coefficient of expansion. I need to drop the tank again to check out the connections again but delving further I see mention of a carbon filter which I assume would be at the breather. Trouble is I can't find a carbon filter and am at a loss to see how the tank breathes. I can see the two small pipes on each side tank are good but....
Anyone got any ideas?
Well-timed silence hath more eloquence than speech.
"A quiet shy boy who took little part in games or sport"
88 High top 2.1 WBX
You're looking at a Bentley, yes? The charcoal filter's part of the US emissions guff which we didn't get, so unless your van's a 'merkin-spec, you don't have one.
The breathing's done through a tiny vent hole in the filler cap.
The problem's probably all the cross-over pipes on top of the tank, and to-from the expansion tanks in the arches. They're needed because of the shape of the tank, with that big valley in the middle. The ones to the expansion tanks can be done in situ - the outer rubber easily, the inner rubber (tank to hard plastic) is a bit trickier, but doable. I've not had to do the main cross-over pipe, fortunately. Yet.
Yes this problem is subsequent to me "overhauling" the tank for the second time -the first when I acquired the van four or so years ago. The problem is that the crossover etc. pipes are a complicated spaghetti some of which plug directly into the top of the tank and some of which are pipe clipped. All of this gets covered up as the tank is hoisted into its final resting place so denying physical and visual access. After siphoning off about 10 liters of petrol I poked about with a Keyhole camera gizmo - endoscope - and was able to confirm that all three plug-ins were indeed plugged in and as many clipped hoses that I could see were OK. It also seems that the sensor plate is in position. I do seem to remember a white plastic bell ended component and I saw the open end of this with the endoscope.
Anyone know what this is as I won't find out untill I inevitably drop the tank
Cheers CS
Well-timed silence hath more eloquence than speech.
"A quiet shy boy who took little part in games or sport"
88 High top 2.1 WBX
Thanks for that. I have to do a trip this weekend and will keep the tank around the half empty level as this problem only happened again due to me brimming the tank for this trip. Fortunately I will be able to run the fridge on hook up. As soon as I get back I will remove the tank (Cursed job!) and perform the Bentley leak test out of the vehicle with the loose ends plugged. I will also apply a low level of pressure to each expansion tank and check to see if the vents a/ exist b/are clear. I will also see if the trumpet shaped thing is a figment of my imagination and if not try to work out what function it performs. I have to admit that I am uncomfortable about plug in fuel connections which barring the filler pipe are albeit at the top of the tank and therefore only able to leak when the tank is brimming full or when the fuel has expanded into the expansion tanks. Too many connections for my liking. But I will get to the bottom of it.
Cheers
CS
Well-timed silence hath more eloquence than speech.
"A quiet shy boy who took little part in games or sport"
88 High top 2.1 WBX
no fuel should enter the tanks , hence thre high up position .
they only contain the air that cannot remain in the tank when the tank is full
allowing the fuel to expand and the vapours to be releasd without releasing the liquid fuel
i have done a fair few tanks , never had a problem , and never yet used new seals / pipes
the commonist fault is the filler neck rubber or a perforated tank!
Last edited by billy739 on 29 Nov 2013, 21:21, edited 1 time in total.
Thanks again. I am back from the Dorset trip now and had no problem as the tank was never full. Plus it was freezing cold - so cold in fact tat we had to switch on a fan heater at about 4:00 as summer sleeping kit used - Do!
Anyway I got an idea that the little plastic funnel thing could have been a vapour drain for the battery box. Will see when I remove tank. Will have an overnight stay for a funeral at Dartmoor imminently so will have to wait. I am convinced that the problem lies at the very top of the tank and only occurs if the fuel level gets high in the filler neck. It definitely isn't the filler neck or seal and barring a pinhole in the tank must be a weep at a pipe connection. I wire brushed the tank and gave it a coat of Hamerite and it looked very sound when I had it out. plus all the joints were mechanically sound. Will be able to blow up (not literally I hope) the expansion tanks as I agree the displaced air would have to be released. If it wasn't for the fact that the large bore equalizing tube has to go across over the radiator plumbing you could be more certain that none of the couplings are displaced on assembly.
Anyway I will update when I get the job done. Cheers
CS
Well-timed silence hath more eloquence than speech.
"A quiet shy boy who took little part in games or sport"
88 High top 2.1 WBX
Well it isn't the filler donut as no problem even when nearly full tank. I But as I have eyeballed the plug-ins and clipped connections with my newly acquired camera gismo, I am leaning towards the sender seal. Although it seemed OK I was tempted to put a sealant on it but silicon is attacked by petrol and although the people who took over Hermatite have now reverted to the original petrol proof formula I thought i best to fit as the design intent. Anyway a pressure test off the vehicle will find it.
Cheers
Ken
Well-timed silence hath more eloquence than speech.
"A quiet shy boy who took little part in games or sport"
88 High top 2.1 WBX
