slip joints

[warmshed]

My y-piece has a sensor so that makes me wonder about using standard silicone, they ain't cheap to replace

I've slapped some copper grease on which seems to be doing the job for now but if it leaks again I'll go the silicone route.

Thanks for the advice gents

If you do use the O2 sensor it may be best to use a non silicone sealant, not worth risking damage to your sensor unnecessarily.