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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Re: Fuel tank leak.

Post by white exec »

Is the leak from the seal, or the pipe connections?
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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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My Cars: 1996 XM 2.5TD Exclusive hatch RHD
1992 BX19D Millesime hatch LHD
previously 1989 BX19RD, 1998 ZX 1.9D auto, 2001 Xantia 1.8i auto
and lots of Rovers before that: 1935 Ten, 1947 Sixteen, 1960 P5 3-litre, 1966 P6 2000, 1972 P6 2000TC, and 1975 P6B 3500S
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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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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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Location: Sayalonga, Malaga, Spain
My Cars: 1996 XM 2.5TD Exclusive hatch RHD
1992 BX19D Millesime hatch LHD
previously 1989 BX19RD, 1998 ZX 1.9D auto, 2001 Xantia 1.8i auto
and lots of Rovers before that: 1935 Ten, 1947 Sixteen, 1960 P5 3-litre, 1966 P6 2000, 1972 P6 2000TC, and 1975 P6B 3500S
x 1752

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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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.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
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white exec
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Posts: 7445
Joined: 21 Dec 2015, 12:46
Location: Sayalonga, Malaga, Spain
My Cars: 1996 XM 2.5TD Exclusive hatch RHD
1992 BX19D Millesime hatch LHD
previously 1989 BX19RD, 1998 ZX 1.9D auto, 2001 Xantia 1.8i auto
and lots of Rovers before that: 1935 Ten, 1947 Sixteen, 1960 P5 3-litre, 1966 P6 2000, 1972 P6 2000TC, and 1975 P6B 3500S
x 1752

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.
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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.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
User avatar
white exec
Moderating Team
Posts: 7445
Joined: 21 Dec 2015, 12:46
Location: Sayalonga, Malaga, Spain
My Cars: 1996 XM 2.5TD Exclusive hatch RHD
1992 BX19D Millesime hatch LHD
previously 1989 BX19RD, 1998 ZX 1.9D auto, 2001 Xantia 1.8i auto
and lots of Rovers before that: 1935 Ten, 1947 Sixteen, 1960 P5 3-litre, 1966 P6 2000, 1972 P6 2000TC, and 1975 P6B 3500S
x 1752

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.
Chris
Gazzaman22
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Posts: 76
Joined: 05 Jan 2017, 15:18
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x 2

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.
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Re: Fuel tank leak.

Post by Gazzaman22 »

Apologies - I never updated this when I fixed to explain how I did. Yes so I did eventually get the black cap off and inspected the black O-ring. it had to be replaced as it was a tiny bit kinked, New ring sorted the problem. But my god I was lucky to get away with the hammer an chisel approach to the black cap ring..... It hasn't many notches left on it and it will be pretty hard to remove it again!

Thanks for the help
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Paul-R
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2003 2.0 HDi 110 C5 Exclusive Estate (Gone)
2001 2.0 HDi 90 Xsara Estate (Gone)
x 1369

Re: Fuel tank leak.

Post by Paul-R »

Haha, that's why there's a special tools for removing the locking ring. I also have worried when I've used a blunt screwdriver and hammer in the past.

Thanks for finishing off the post.
As I get older I think a lot about the hereafter - I go into a room and then wonder what I'm here after.

Inside every old person is a young person wondering what the hell happened.

"Trying is the first step towards failure" ~ Homer J Simpson​
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