how can i seal this thread to stop a diesel leak

[GUMPY]

 

 

But a leap to the conclusion that diesel dissolves PTFE rather than it just not being very good at sealing (or technician error!) is a pretty big assumption.

 

Same thing happens sometimes with water. PTFE just isn't a very good sealant, but doesn't mean water dissolves it!

Following on, I rarely have had a water joint leak when using PTFE but all my diesel joints with PTFE leaked. What conclusion would you draw in my position?

[bizzard]

Diesel, like paraffin is more searching than water. I wouldn't use PTFE tape on diesel fuel joints either.

[MtB]

Following on, I rarely have had a water joint leak when using PTFE but all my diesel joints with PTFE leaked. What conclusion would you draw in my position?

 

 

As Bizz points out too, that diesel is thinner than water.

 

May I suggest you fill a container with diesel and put a piece of PTFE tape in it, then see how long the tape lasts? If as you assert, PTFE tape is soluble in diesel, I'd suggest it should disappear or disintegrate.

 

I've never tried this myself by the way, but I'm about to. Shall we compare results in a month or two?

[cereal tiller]

Diesel, like paraffin is more searching than water. I wouldn't use PTFE tape on diesel fuel joints either.

Agreed,Diesel fuel will soak into P.T.F.E. but not if a sealant liquid is covering the tape,as i mentioned a while back

 

CT

[GUMPY]

 

 

As Bizz points out too, that diesel is thinner than water.

 

May I suggest you fill a container with diesel and put a piece of PTFE tape in it, then see how long the tape lasts? If as you assert, PTFE tape is soluble in diesel, I'd suggest it should disappear or disintegrate.

 

I've never tried this myself by the way, but I'm about to. Shall we compare results in a month or two?

I don't disbelieve you, it just feels that way

[MtB]

I don't disbelieve you, it just feels that way

 

 

Professionally I've made hundreds, possibly thousands of joints on oil lines using PTFE with never a leak.

 

I disagree with CT's comments. Diesel wets the surface of PTFE tape making it go transparent, but it does not dissolve it in the precise technical meaning of the term, in my experience.

 

Difficulties with PTFE taped joints leaking are almost always caused by not enough tape, or it being would on too loosely. It works less well on roughly machined surfaces than liquid sealers as liquids more easily find their way into the micro-surface irregularities.

[bizzard]

 

 

Professionally I've made hundreds, possibly thousands of joints on oil lines using PTFE with never a leak.

 

I disagree with CT's comments. Diesel wets the surface of PTFE tape making it go transparent, but it does not dissolve it in the precise technical meaning of the term, in my experience.

 

Difficulties with PTFE taped joints leaking are almost always caused by not enough tape, or it being would on too loosely. It works less well on roughly machined surfaces than liquid sealers as liquids more easily find their way into the micro-surface irregularities.

And winding it onto the fred the correct way or its liable to be chased off.

[Guest]

We used to PTFE tape and Stag together on heater oil feeds.
I can never type PTFE without thinking of an apprentice who thought it was an acronym for Pipe Tape For Engineers.

[Canalwatcher]

We used to PTFE tape and Stag together on heater oil feeds.

I can never type PTFE without thinking of an apprentice who thought it was an acronym for Pipe Tape For Engineers.

Neither will I now!

 

Mick

[RLWP]

That is a mjor blow,

 

 

Not really, there are a lot of modern sealants about that work very well

 

Richard

[Guest]

 

Not really, there are a lot of modern sealants about that work very well

 

Richard

True enough but I grew up with that stuff! It is as much a part of my youth as Player's No 6, Party Seven cans of beer, and British Anzani outboards

Blue Hylomar seems good stuff.