Seeping pipe connection to Loft Cold water

[KennyA]

Had a problem with hammering noise coming from pipes (triggered by hot water, though it could be eased if you put the cold water on).
Went through everything i could, checking joists etc. Problem appeared to be the ballcock in the loft cold water tank.

Ive replaced it but for the life of me i cant stop seepage out of the nut for the main connection. Though ive only tried
1. Going tighter, getting to the point i'm not sure i can get it any tighter!
2. adding the pfte tape to close any gap

Still getting seeping from the nut, left a tea towel wrapped around it overnight and its soaked this morning.

Im a real newbie and feel the answer is obvious (more tape??) but seems the majority of the job is done, i really dont want to bring someone in but im all out of ideas and know my limits, which are pretty low it has to be said.

For info - I wrapped the tape around the brass thread of the ball cock, no tape used on the cold main thred/nut. See photo

 

[Rtplumb]

It’s best if you use a 15mm fibre washer to seal the connection. After work on old connectors that require a fibre washer, always put on a new one. You can obtain washers from Amazon, screwfix, tool shed etc.

 

[KennyA]

It’s best if you use a 15mm fibre washer to seal the connection. After work on old connectors that require a fibre washer, always put on a new one. You can obtain washers from Amazon, screwfix, tool shed etc.

Thank you, I’ll do just that. Much appreciated