Washers for brass hose fittings

[Poey50]

I want to fit a tap just upstream of my primary fuel filter to help with filter changes. I've got the brass chrome-plated fuel tap and brass hose tails but is any kind of washer required betwixt tap and tail?

 

[LadyInBed]

Brass pipe is normally connected to a tap using an 'olive' to compress and seal the connection.
I would have thought copper pipe would be better than brass, as it is softer and takes vibration better.

 

[sailorman]

I want to fit a tap just upstream of my primary fuel filter to help with filter changes. I've got the brass chrome-plated fuel tap and brass hose tails but is any kind of washer required betwixt tap and tail?

i have a brass 8mm compression gas cock in the copper pipe supply line

 

[Poey50]

I should have mentioned that the fuel line is rubber pipe. My question is whether there needs to be any kind of washer between the brass tails where one end of the tail is inserted in the pipe and the other end is inserted in the tap.

https://www.ssldieselparts.co.uk/hose-tail-fuel-taps-bhft-p-716.html

 

[macd]

They're tapered threads: any washer would be likely to prevent it sealing. Use a liquid sealant compatible with your fuel, not PTFE tape.

 

[Poey50]

I think I've answered my own question from an old thread. I should have searched more thoroughly.

They are tapered fittings so, as I understand it, no washer but there is some talk about PTFE which seems on balance not to be recommended unless liquid PTFE.

Edit: Thanks macd - our posts crossed.

 

[Poey50]

Just a quick follow-up. Should the tapered hose tails be capable of a leak-proof fit for diesel without sealant?

 

[David2452]

Just a quick follow-up. Should the tapered hose tails be capable of a leak-proof fit for diesel without sealant?

Yes if tightened enough, but the great thing about liquid PTFE though, is that it helps lubricate the threads during tightening so fewer sheared hosetails as well as sealing properties. No nonsense liquid PTFE from Screwfix is as good as anything for these small joints and I use it on even smaller ones (1/8" BSPT to 4mm hosetails) almost daily

 

[Poey50]

Yes if tightened enough, but the great thing about liquid PTFE though, is that it helps lubricate the threads during tightening so fewer sheared hosetails as well as sealing properties. No nonsense liquid PTFE from Screwfix is as good as anything for these small joints and I use it on even smaller ones (1/8" BSPT to 4mm hosetails) almost daily

Brilliant, thanks.