Leaky TD4 fuel tank & plastic debris in the fuel tank & fuel content level

Had a bit of an issue with a leaky fuel tank on a TD4. Fuel would leak out of the top area of the fuel tank and make its way down & thus drip off the bottom of the fuel tank retaining bar onto the drive - on initial inspection the fuel pump & black ring had come completely loose!

Refitted everything and it still did the same.

Put it down to an 'old' pump seal, anyway replaced it for a new one and whilst I had the pump out, I took a few pics, sort of a guide of where parts went back etc.

On looking at the fuel tank contents, the flash exposed some debris in the bottom of the tank, in particular a 'white' plastic bit, looks like it may have snapped off the fuel pump, not sure if it belongs to the 'old' pump that was removed or the 'new' one that was fitted in 2007??

I know the last owner replaced the fuel pump back in 2007 and I know he wasn't a mechanic, the pump and black ring had actually worked themselves loose last week - I don't know if this is a common fault or just that the last owner didn't do a good job at fitting the new pump?

The pump and black ring could have been loose for some time, I don't know.

Firstly the 'white' plastic debris seen in the pic, is there anyway that can get sucked up into the fuel pipeline?

Secondly if the fuel gauge on the dash is on the last red marker, how much fuel roughly is in the tank, if anyone knows?

Because I'm thinking of draining / siphoning the tank to clear any debris out from the tank.

The pictures show the level of fuel in the tank and the dash gauge would read 1/4 of a tank - to me there seemed to be more fuel in the tank than a 1/4?

How do you know if the 'float' reading is correct or not?

Are there any 'care' procedures when removing the pump from its tank housing, with regard to the 'float' arm?

Thanks in advance.

I wonder if the previous owner made the mistake of sliding the sealing ring onto the pump then trying to fit it, its almost impossible to do this way, better to sit the sealing ring into the pump hole then slide the pump in and it should seal properly.

I suspect the bits in the bottom of the tank are too low down to get sucked up and the pump body has a built in filter type mesh as well so probably ok.

The last owner didn't really go into it, he just mentioned he'd replaced the pump and there is a receipt to back him.

I presumed it was done properly!

On discovering the pump the way it was, loose bobbing up and down, it would appear not.

When I took it to the Land Ranger garage, they said the same thing you have to remove the pump completely, then put the 'seal' in place first then push the pump in place.

So on that advice I followed their instruction, which worked but I found that the 'float' arm gets caught - see picture

Which causes a bit of a tight fit, I'm just hoping that no damage can be caused or was caused when doing this?

As for the plastic bit in the bottom of the tank, I'm wondering where its come from, the old pump or the new one??

If the new one is damaged, I'd rather know about it and not have any more leakages.

Also I'm the sort of person, who now has seen that bit will want to get it out of the tank!

At the minute the fuel level indicator is on the red, indicating it needs fuel, so I will top up to around 3/4 of a tank and see if the leak shows itself again.

The leak always seemed to appear coming from under the 'white' tab (left side) if your looking from the rear of the td4 to the front.


The garage suggested, if with a 'new' seal the leak persists, then take out the pump with it actually running to see if fuel is being sprayed upwards towards the white tab.


As the fuel level is way below that of the white tab and the only way the fuel could get there is to be sprayed up!

The pump was fully seated flush with the 'new' seal and the black locking ring was tight as can be, I did it myself and made sure it wasn't coming undone.

If I've taken the pump out, I've released the tank pressure, so if I put the pump back, isn't there a new pressure created there now?

If so could the pressure in the tank cause the fuel to reach the white tab area??

How does the tank pressure disperse around the system and out, when its main parts have been removed / replaced?

fuel lines can be under pressure but the tank isn't, it has a vent.

On looking at the pump in general its a sealed body all the way round, so how fuel could be sprayed up, and through its sealed body I don't know??

Unless the round circular molding that the seal sits in, is cracked by or under the white tab?

Its a mystery why there would be a fuel leak just by / under the white tab? :doh:

Don't know how much was leaking, but if the pump was loose you would get diesel splashing out of the tank on cornering. This would take time to run down the outside and drip off. If it's no longer leaking I wouldn't worry - your filters are there to prevent problems.

hello looking at your post about your leaking td4 fuel tank i have owned my td4 02 plate 6 months now and my tank is leaking in the same place as yours was leaking on the left i was just wondering if you was able to find what was the cause to your leak and a possible fix to the problem thanks .

The leak on the fuel tank pump looks a bit like this.

Sadly no conclusion.
Is it possible that the white ring attached to the tank can come adrift or leak? Can't see that it comes off, but with a good seal a leak from under the white ring fixed to the tank is best possibility for my problem.

I'll ask @Alibro if he still has his fuel tank lid and maybe he can see if the ring is a separate component?

andyfreelandy said:

The leak on the fuel tank pump looks a bit like this.

Sadly no conclusion.
Is it possible that the white ring attached to the tank can come adrift or leak? Can't see that it comes off, but with a good seal a leak from under the white ring fixed to the tank is best possibility for my problem.

I'll ask @Alibro if he still has his fuel tank lid and maybe he can see if the ring is a separate component?

Click to expand...

My fuel tank is in two bits now with the top cut off and the sender removed so I don't think I'll be able to help much unfortunately.

Ahah, but that is the point !!

You have the top removed and the sender out - just what is required.

If you still have the top, could you see how the white threaded ring is held to the tank neck for me please??
Mine might be leaking between the two items on the tank neck.

Cheers Ali

andyfreelandy said:

Ahah, but that is the point !!

You have the top removed and the sender out - just what is required.

If you still have the top, could you see how the white threaded ring is held to the tank neck for me please??
Mine might be leaking between the two items on the tank neck.

Cheers Ali

Click to expand...

Sorry mate, I miss understood.
I'll get a look at it over the weekend.

Anything with this. Mine is leaking in the same way, from the white tabs ..

Ho joy ..... New pump, new seal but still leaking. Especially on a fuller tank going around corners. You can see the fuel flow out from the tabs !!!
I might just gasket them up. I'm not sure if these are part of the breather system which has failed frustrating...

It would seem that the seal naturally fits in one way.. flat part to the top... I'm wondering if it should go the other way..

OK so I solved my leak from the top.
Fitting the seal is tricky and, as has been said, the float arm gets in the way.

What I did to get it positioned right was to fit it to the pump. Carefully feed the float arm and pump into hole.

Lift pump up about halfway where there is a reduced diameter on the pump.

Slide the seal down and press it firmly home onto the tank rim.
Slide the pump down flush.

Tighten ring by hand as it can go cross thread. When you've done a turn or 2 I used some large pipe pliers to turn it another 1/4 turn.

All good. Mine looked like a leak under the white tab but fitting the top seal carefully and correctly stopped all leaks.
Fuel tank cradle won't rust on that side at least!!!

Sorry guys, I forgot about this. I did look at the bits I could find but couldn't see anything to help. I think I threw away most of it.
Good to hear you got it sorted.

andyfreelandy said:

OK so I solved my leak from the top.
Fitting the seal is tricky and, as has been said, the float arm gets in the way.

What I did to get it positioned right was to fit it to the pump. Carefully feed the float arm and pump into hole.

Lift pump up about halfway where there is a reduced diameter on the pump.

Slide the seal down and press it firmly home onto the tank rim.
Slide the pump down flush.

Tighten ring by hand as it can go cross thread. When you've done a turn or 2 I used some large pipe pliers to turn it another 1/4 turn.

All good. Mine looked like a leak under the white tab but fitting the top seal carefully and correctly stopped all leaks.
Fuel tank cradle won't rust on that side at least!!!

Click to expand...

Pleased to hear you got it sorted... So which way did you have your seal fitted... bevel side up U or flat side up __?

Flat side up. Easy to get it trapped or not seated flat.

Make sure carpet is back and you have a good torch to see all around the seal.

andyfreelandy said:

Flat side up. Easy to get it trapped or not seated flat.

Make sure carpet is back and you have a good torch to see all around the seal.

Click to expand...

I have removed the carpet and the seal sits in the groove correctly. The pump sits in flush with the seal seated correctly yet I still get fuel seeping out. its bloody infuriating. I'm considering using some Hylomar Universal Blue to seal the thing up once and for all...

LandOthefree said:

I'm considering using some Hylomar Universal Blue to seal the thing up once and for all...

Click to expand...

Use some plumbers silicone grease to sparingly lubricate the seal (new seals are pre-lubricated). I've found that if the seal can't slide on the clamping faces, then it doesn't seat properly and leaks.

Nodge68 said:

Use some plumbers silicone grease to sparingly lubricate the seal (new seals are pre-lubricated). I've found that if the seal can't slide on the clamping faces, then it doesn't seat properly and leaks.

Click to expand...

Thanks fot that... will do.