Problem with pump Gardena 4000 / 5

[Fausty]

Hello,

The problem is that it engages correctly when it arrives at a pressure of 3 bar it stops as it should, but then the pressure drops quickly.
The pump is no early youth, she has between 5 and 10 years.

Would you possible reasons for this problem.

Thank you in advance

[Gaston]

There is a leak somewhere.

Not necessarily visible: perhaps a check valve that is stuck ...

[arun]

Hello
As said there is a check valve
I put the link to download the PDF file and see page 7
https://www.google.fr/url?sa=t&rct=j&q= ... OA&cad=rjt
cordially
Claude [/ img]

[Fausty]

Hello,

It was indeed the check valve, but it was not dirty, just the seal that had some signs of weakness and who had moved.

Anyway thank you very much for your quick and effective aid