Boss White will set hard after a while and virtually concrete the threads in if you use it to excess. Cured good quality Silicon is VERY tough to remove. I usually put a couple of turns only of PTFE on the threads then a smear of Boss white or Hawk white on the flat mating faces at either side of the fibre washer. The PTFE prevents the threads seizing in whilst the fibre washer provides the actual seal. Use a full (proper) immersion spanner to remove and refit the immersion. Tap it to loosen and retighten, simple force will buckle the cylinder. Hint don't connect the cable until after you have finished and tested for leaks as it will have to come off again to tighten a bit more if required)
I did this the other day. Mine came with a fibre washer and I simply put a couple of turns of PTFE tape around the threads for luck (although somebody will be along shortly to tell me I needn't have) and then just tightened up. Don't overtighten while the cylinder is empty but wait until you've filled it as the water makes the whole thing more solid which helps.
I found that it weeped a bit when the cylinder was first filled, but I managed to get about another 1/4 turn on it - I figured that when the fibre washer got wet it become more compressible. Was fine after that which was a relief as I didn't want to have to empty the tank again!
A smear of silicone on the gasket is all I've ever needed to use and with that you don't have to wring it off and back a quarter turn to make it watertight!...
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.