Non return valve on fuel line

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steve_earwig
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Re: Non return valve on fuel line

Post by steve_earwig »

Found a picture here https://www.frenchcarforum.co.uk/forum/ ... 7b#p385574

ffs, I forgot what happens when you put "lucas epic" in a search engine :roll:
Unskilled meddling sin©e 2007

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TRANSPORTER
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Re: Non return valve on fuel line

Post by TRANSPORTER »

:) Was kinda hoping beyond hope when I started reading that, that the job was an insitu task, typically it’s a pump out meaning cam belt off etc etc.
My thoughts on the stop solenoid are still there, that is it closes off when ignition is switched off enough to shut the fuel off, but maybe it is worn or something and overnight allows fuel to seep back down the lines.
I’ve no air bubbles in my fuel lines now so I’m air tight on the delivery side. If air tight then I’m presuming that the leak off pipes must be fine?
Also it seems to be worse in cold weather!! But glow plugs are brand Peugeot main stealer Beru’s, so if anyone would like to throw any ideas out there aswell feel free please
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Re: Non return valve on fuel line

Post by steve_earwig »

TRANSPORTER wrote: Wed Dec 09, 2020 3:40 pm ...but then the next morning it fired up and ran for approx 2 seconds then cut out.
Maybe that was all the fuel upstream of the valve (possibly eliminating the cut off solenoid)

Cold weather - maybe the pump has a harder job pulling the thicker diesel up :?
Unskilled meddling sin©e 2007

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Re: Non return valve on fuel line

Post by TRANSPORTER »

I know it’s chilly but I’m not lighting a fire under my tank to warm the fuel :)
Anyway this morning after a rainy night and mild temperatures she started first turn of they after a single cycle of the glow plugs. I did see one air bubble leave the fuel filter housing as I cranked her over but it was small.
Struggling to work out this problem now, luckily it’s only cost me just over £100 mainly in glow plugs.
I might just go ahead and change the leak off pipes over the weekend if I get time but I really don’t see them being the problem.
WillNZ
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Re: Non return valve on fuel line

Post by WillNZ »

What type of nrv are you using? Electric or mechanical? If it is mechanical, they are really not guaranteed to seal 100%, that is why electric solenoid type valves are used. Apart from the fact that a mechanical nrv does require a pressure to allow flow (so will restrict flow by its very nature) while an electronic one does not restrict flow when energised...

I assume you fitted it in the area you clamped off the fuel line? If so, test its efficiency by clamping the fuel line just before the nrv and see if it then starts straight away. Do this over a week or so alternating between clamping it and not. That will tell you if it is actually doing it's job or leaking just enough to allow the line to drain a bit.

I have replaced several nrv's in my fleet of HDi's. The nrv sits at the rear of the injection pump and is relatively easy to get to. Not ever worked on the 1.9 so cant comment on ease of replacement there unfortunately. Must go on a goooooogle fest and see if I can find out... :cheesy:
Serial 406hdi licker :cheesy:
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Re: Non return valve on fuel line

Post by PeterN »

To find the fuel heater (if it has one) just follow the fuel lines.

Peter
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Re: Non return valve on fuel line

Post by TRANSPORTER »

Wiinz, cheers for your reply, I’m using a mechanical nrv, and to be honest it’s not doing the best job. I think because it is such a slow movement of fuel back down the line it doesn’t shut it off if there was a good amount of pressure pushing back against it. I will try clamping again just before the nrv, and I bet I know it will start perfectly.
At the moment if she doesn’t start straight away I resort to the primer bulb, and I do notice about and inch or so in length of micro bubbles in the clear pipe that feeds the fuel injection pump, they are usually about again an inch down the pipe.
When she’s running she pulls like a train and is very smooth so no complaints there.
I have been busy with one snapped and one nearly snapped rear anti roll bar bush clamps, Peugeot don’t make them anymore and a big search ensued, which ended up in finding one new one, still not arrived, but I got the welder out and fabricated the originals so they are back on but awaiting new bushes though.
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