Fuel tank leak.

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Gazzaman22
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Re: Fuel tank leak.

Post by Gazzaman22 »

I'd say I rotated it half a turn, by tapping but now it's as tight as I can get it.

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white exec
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Re: Fuel tank leak.

Post by white exec »

Is the leak from the seal, or the pipe connections?

Gazzaman22
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Re: Fuel tank leak.

Post by Gazzaman22 »

Its seems to be coming from the black capping on and between the sender unit(yellow unit)

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Re: Fuel tank leak.

Post by Gazzaman22 »

Pipes are drip free

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white exec
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Re: Fuel tank leak.

Post by white exec »

C5II diesel tank unit_2.JPG
Might be worth removing all the bits #8,5,2,6... and cleaning up with alcohol and drying off, and reassembling with the O-ring and surfaces coated with Hylomar Blue, which is fuel-proof. Hylomar Blue available on Amazon.

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Paul-R
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Re: Fuel tank leak.

Post by Paul-R »

I would think long and hard before using any instant gasket product.

First thing is to clean everything up (pay special attention to the O-ring) and reassemble, providing there are no obvious cracks or distortions. If that doesn't work then same again with a new O-ring.

Be sure to remove any grit from the threads or sealing surfaces.

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white exec
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Re: Fuel tank leak.

Post by white exec »

Hylomar is not instant gasket, Paul - it's a simple thin gasket/seal/O-ring sealer, much like Hermetite red, but more effective. Difference is that HB is fuel-proof. Thickness is not a lot different to vaseline. It also allows the joint to broken again, if required.

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Paul-R
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Re: Fuel tank leak.

Post by Paul-R »

I've used both blue Hylomar and red Hermetite (and the green one as well) and concur that it doesn't set hard but it shouldn't be necessary is my point.

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white exec
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Re: Fuel tank leak.

Post by white exec »

Agree, it shouldn't, but if there's some minute crack or surface irregularity, it might just remedy the leak.
Quite agree that a new O-ring should be fitted.

Interestingly, a Bosch recommendation for O-rings and cover seals in their diesel injection pumps is to lightly smear them with Vaseline before fitting. This does work: I had a weeping injection pump top cover, fitted a new (in-groove) rectangular gasket, and still a leak. Bosch technician here recommended the Vaseline and "nothing else". Did it on a new seal, and it worked.

Gazzaman22
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Re: Fuel tank leak.

Post by Gazzaman22 »

Thanks for all the info lads. I'm actually blessed as I have a spare car for parts, so tomorrow I will take my leaky car to my old mans farm where the spare is parked. And clean up the all I can clean, and reassemble. If that doesn't do the trick I think should I swap all including sender. And see how that goes.. I would like the spare car to be operational as the old man still drives it down an old lane, to where his farm is. He uses it as his tractor!
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Paul-R
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Re: Fuel tank leak.

Post by Paul-R »

Are the two cars exactly the same model? Same engine? Same model year? Petrol and diesel are different. Some diesel engines have different injection systems and will probably make for a different pump/sender unit.

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white exec
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Re: Fuel tank leak.

Post by white exec »

Diesel engines usually have no pump in the tank, just pick-up/return and level sensor.
The O-ring (Fuel Tank Seal) is available from Citroen. Two types, depending on RP number.

Gazzaman22
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Re: Fuel tank leak.

Post by Gazzaman22 »

More or less the same, yes a 2007 and a 2008 models, both diesel and 1.6, one has the sat nav package in it.