Pump leaking??

[billynoclue]

Could this be the problem with my pump!? http://i1193.photobucket.com/albums/...ps3bcd593e.jpg Looks like there is lime scale build up coming from the thread of the top cylinder. This is a stuart turner monsoon negative head 2.0

 

[billynoclue]

Pump keeps hunting all he time

 

[lame plumber]

dripping tap anywhere? or foxes in the bathroom

 

[billynoclue]

no drips now - bit worried about the lime scale line in the picture from the top vessel - should I be worried? no dripping taps now(had to change the cartridge)