Hello Lorenzo,
all fuel-pumps i know which where leaking had the same problem.
It leaks between the plastic top and the aluminium chasis.
- pump.jpg (36.92 KiB) 7395-mal betrachtet
To repair this you had to clean the surface of the plastic top with alcohol or fuel, i use therefore cotton-sticks (q-tips)
After this i use epoxy (i.e. UHU plus), mix it and put a little bit around the alu chasis at the plastic surface
- epoxy.jpg (36.98 KiB) 7395-mal betrachtet
Next i use my hot air gun, normaly used for smd unsoldering, switch it to lowest temperature and air preassure, heat the epoxy until it gets fluid and blow it with the air stream over the surface and into the gap between the alu chasis and the plastic.
- hot-air-2.jpg (57.15 KiB) 7395-mal betrachtet
- hot-air-1.jpg (29.22 KiB) 7395-mal betrachtet
After its hardened it will look like this and will be leak-proof for years. I did this 8 years ago at the org. fuel pump of the 1600i engine in my old convertible. Its still ok.
- pump-sealed.jpg (46.46 KiB) 7395-mal betrachtet
I never had leaking o-rings. But if you disassemble your fuel pump and unmount the o-rings, they will get larger and you couldn't use them for now. Wait 24 hours and they will fit again.
Years ago i bougth some o-rings. At the moment i only found the larger one. Somewhere should be the same amount of the smaller ones.........
- o-rings.jpg (38.67 KiB) 7395-mal betrachtet
I never tested them. But if you like to it. Shippment to Italy will be 1,50 €. You can spent me a beer when we will meet us sometimes. In this case please mail me the adress.
And please, don't spam me with e-mails, 20 of them are 19 to much. If i get enough time to write a answer, i will do it.
cheers Manfred