1.4 Tdi LUK 038145209E tandem fuel pump rebuild.

Little Dog

A2OC Donor
European-Union
While addressing a starting issue recently I noticed my fuel pump had leaked. I couldn’t find the exact source of the leak but coolant pipes under the pump smelt of diesel and were softening and ballooning.

I have bought a comprehensive seal kit but have no instructions for fitting. Could anybody point me towards suitable guidance? Thank you.


PS I shortened the screws and tightened everything up a few years ago.
 
Bump.

Anybody fitted one of these? Any tips? I don't want to end up with a pile of bits and a £600 bill for a new pump :(

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Thanks Spike I think that is the pump I have. There is enough there to get on with the job.

Why the last vac? I assume he is testing for leaks?

Will take some pics and report how I get on.

A bit heavy handed wasn’t he :)
 
Just a few screws to remove but need to remove some pipes and wires to gain access:

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I had to cut the fuel and vac pipes. Try to avoid, the fuel pipes are on back order from Germany and the vac pipe is only available in a 1m length.

Clean pump avoiding getting solvent inside:

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Strip down:

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Edit 240314, at this point check the black pressed steel cover for flatness and wear. If there are any issues the repaired pump will leak again within months as this one did. Replace the pump.
The second failing of this pump however may not be due to the cover seal failing https://www.a2oc.net/community/index.php?threads/how-does-a-tandem-pump-work.51970/page-2

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Substitute old parts with new:

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See next post.
 
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Reassemble:

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Edit 240314, this is the head to pump gasket not to use. Two blue silicone blobs are missing. These gaskets, as did this one, leak oil. I use genuine Audi gaskets, Elring gaskets are also recommended by other members.

One O ring left over but could not find this anywhere on the pump or in pump repair videos. Anybody know where it goes, on the vac output??
A vice is very useful as is a good quality Torx set.
 
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Great work, philward. Besides the work on the tandem pump, I'm particularly loving your choice of kitchen roll. :)
Where did you buy the seal kit?

Cheers,

Tom
 
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I may be wrong but is the seal for the drain plug ...

View attachment 27228

you can see the old seal in your photo

Nope, I'm not sure what that black ring was but it wasn't the seal.

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Good news though the car is running fine on its rebuilt pump. Reassembly is simply a reverse of the disassembly process. One thing to watch though, make sure your battery is well charged because it takes some cranking to draw the fuel through the pump.
 
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Just been checking my threads and it appears photobucket have mucked them up. How do we post pictures now? I'm sure there must be guidance but I can’t find it.
 
Just been checking my threads and it appears photobucket have mucked them up. How do we post pictures now? I'm sure there must be guidance but I can’t find it.

I always right click on the photo on my laptop and then select edit and crop it down to under 2mb , then in the quick reply window at the top select 3rd one from right "insert image" , when the window pops up direct it to the folder you have the photo in and select the photo ..
 
Yes you can rebuild the tandem pump but be aware there are two different designs of gasket and they are not interchangeable so you must get the correct one for your pump. If your car is high mileage then good chance the drive dog that is driven by the camshaft will be badly worn. THIS PART IS NOT IN THE RESEAL KITS. In the end I gave up with my LUK pump and bought a far better and much cheaper Bosch pump. Had a look on ebay and found this one
https://www.ebay.co.uk/itm/Tandem-V...038145209Q-038145209-F009D02799-/263552032687
or this company for reseal kits
https://www.darwendiesels.com/home/12771-tandem-gasket-kit-.html
https://www.darwendiesels.com/home/12773-tandem-gasket-kit-.html
Verify you order the correct one for your pump. I am sure there are also companies in Rome that will be able to supply the parts.
Use the part number on the pump and do an internet search for reseal kits and replacement pumps.
 
Hi @cooper yes the seal kit did work but only for about 18 months. The pump began to leak fuel again.
Also the pump to head seal, the one @audifan mentions there are two versions of, was less than OEM quality and quickly began leaking oil. If you go down the seal kit route there is an easy fix for the oil leak.
I came to the conclussion LUK pumps are less than great and replaced it with the Bosch pump audifan recomends. Shop around, I paid less for my pump at AutoDoc. The pump is supplied without the head to pump seal so be sure to order an OEM quality seal.
Audifan has the reply well covered so I just have one further comment. What ever your decision do not delay. Diesel will ruin your electrics and cooling pipes under the pump. From memory the pipes from Audi were around £130.
 
Yes as @philward reminds me of all the extra cost to replace all the rubber hoses and repair the electrics only to have to repeat everything again in my case after only 3 months save yourself time money and frustration and replace the pump NOW. I think I also paid less than current listed above that was only to show they are available and what to look for. I do not think that I would risk buying a second hand or even a "refurbished" pump and can honestly recommend the Bosch pump.
 
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In this period more pains than joys.
I have two other problems the egr valve, already changed in 2015. Now I would like to remove it, I found this kit, see attached file;
some of you I think I have already done. What do you recommend? On the German site I read about checking the phase between camshaft and crankshaft that must be between + 3 ° - -3 °. It can be checked using the VCDS function. There is a screw for regulation, do you know where it is? Last problem with oil from the turbine I read about trying to replace this o-ring (8Z0 129 646 or 3C0 129 646
 

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I would check with your authorities in Italy to see if it is legal to remove the EGR first. If you are legal then remove it, if not I am afraid you will have to keep it fitted. 3 years seems a short period of time for it to be causing problems again. How you checked it in VCDS? Also for the phase angle I would see what you have first before you worry too much about changing it. Clean the outside of the turbo and then recheck it again for leaks in say 500km, if it is still dry do not change it. Also look around above to see if the oil is collecting there and not from the turbo. If the tandem is leaking you will kill all the rubber hoses so change it as soon as possible. While you are changing the pump you could clean and check all the pipes to the EGR at the same time. Try to cover up the hoses if they are not yet spongey or melted by the diesel as they go very quickly.
 
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