PTFE tape, heat proof?

[Ohlin Karcher]

My drip feed diesel heater, a Dickinsons Newport, is getting a service.
The brass fittings which screw into the cast aluminium metering valve box are a slightly loose fit.
They were sealed with some brown stuff but it has all flaked away, and need something to seal the threads.
The area gets hot, and a leak of hot diesel on to the wooden floor would be very risky!
Can I use PTFE tape, or is there hopefully something better, maybe stove mastic or something?
Heatproof PTFE tape woukd be ideal but I have never heard of it.
Thanks for suggestions.

 

[colhel]

It could be this stuff

https://www.packsealer.co.uk/spares...WfoH5vsnXRgcjWXFYkFT6MYT7rTqA6CxoC_LEQAvD_BwE

 

[Ohlin Karcher]

It could be this stuff

https://www.packsealer.co.uk/spares...WfoH5vsnXRgcjWXFYkFT6MYT7rTqA6CxoC_LEQAvD_BwE

Thanks for the link, but those are spares kits for the machines which heat-seal plastic bags.

 

[vyv_cox]

Liquid PTFE is brilliant stuff, Screwfix and no doubt many others sell it these days. PTFE tape and small nozzles do not go well together.

PTFE is good for more than 200 degrees C.

 

[rszemeti]

Can I use PTFE tape, or is there hopefully something better, maybe stove mastic or something?
Heatproof PTFE tape woukd be ideal but I have never heard of it.

PTFE tape will be fine, there is no such thing as "heatproof PTFE" as all PTFE is heatproof as standard, it's made from err .. PTFE which is good to around 300 degrees C, which is far higher than you will ever need.

Melting point is 327 C!

 

[rogerthebodger]

If I have a critical joint to make I use Chesterton 850 PTFE tape which is 100% PTFE unlike the normal tape.

https://chestertondocs.chesterton.com/Lubricants/tdms850_EN.pdf

Rated max temp is 240 to 260 C.

 

[Ohlin Karcher]

Excellent advice thanks very much all!

 

[colhel]

Thanks for the link, but those are spares kits for the machines which heat-seal plastic bags.

Yep sorry, I posted in haste as dinner was ready.
try this https://www.affixit.co.uk/Self-Adhe..._UNY5J9_6I65lGmV0md2cyUTEnvomfqRoCJpQQAvD_BwE

 

[rszemeti]

Yep sorry, I posted in haste as dinner was ready.
try this https://www.affixit.co.uk/Self-Adhe..._UNY5J9_6I65lGmV0md2cyUTEnvomfqRoCJpQQAvD_BwE

This is not suitable for use as a thread seal tape.

 

[Ohlin Karcher]

Success :encouragement: I used Screwfix PTFE tape by the way.

 

[awol]

Don't get it too hot!

From Wikipedia
Perfluoroisobutene (PFIB), also known as 1,1,3,3,3-pentafluoro-2-(trifluoromethyl)prop-1-ene, is a fluorocarbon alkene. It is a hydrophobic reactive gas with boiling point at 7 °C. It is a strong electrophile.
PFIB is about 10 times as toxic as phosgene. Its inhalation can lead to pulmonary edema, which may be fatal. Onset of symptoms can take 1-4 hours after inhalation. Treatment is based on management of the pulmonary edema (usually with high-dose corticoids and other medication/measures) and associated disorders (e.g. heart failure, hypocalcemia etc.). Many cases resolve within 72 hours without major long-term effects.
In contact with water PFIB undergoes rapid hydrolysis, producing various reactive compounds and fluorophosgene.
PFIB is a product of pyrolysis of polytetrafluoroethylene (PTFE), one of the substances causing polymer fume fever.
It is a Schedule 2 substance of the Chemical Weapons Convention.

 

[colhel]

This is not suitable for use as a thread seal tape.

True. My bad

 

[macd]

Liquid PTFE is brilliant stuff

+ a lot, Vyv.
I still keep tape in stock but probably used it around the last time I shot a roll of film.