Lotus Elan and Lotus Elan Plus 2 Forums

Self-amalgamating tape has been used to fill the voids in threaded joints for many years not to provide mechanical strength to the joint.
If needed, epoxy will breakdown when subjected to enough heat.

I used to work on a gas terminal on instrumentation, we used either ptfe tape or a pipe sealant such as Swac. Both of those joints could be easily unscrewed without resort to heat. The advantage of the ptfe tape in your circumstance is that you can always wrap a couple of extra layers on the thread if the outlet is pointing the wrong way, although better solution would be to run the tapered tap in an extra part turn as you really don?t want more than about 6 layers of thin ptfe tape on a joint.

All sorted, thread cleaned up (thanks to Mike for the loan of appropriate tap) new heater valve installed.
Thanks for all the advice.
Malcolm

I've used the gas tape several times and never had any leaks or any movement and it allows you to position the valve were it need to be.

TonyR