In article 586uc.17891$mm1.12389@fed1read06,
"larsen-tools" wrote:

I read somewhere that it's not a good idea to uses Teflon tape on threaded
joints in a hydraulic system.
Is that correct and if so, why?

If you did a hack job of it and stretched tape across the openings, I
could see shreds of tape getting into the fluid stream, and perhaps
sticking in valve ports, etc. If you did a proper job it should do
nothing of the sort. You would want to be careful to get it all out when
removing fittings, as that would be a point where carelessness might
result in shreds going into the system.

I expect that you can read somewhere that it's bad, and you can read
somewhere else that it's good. If the system is assembled and has been
run, there's no benefit to dissasembly now, IMHO. Any shreds that are
likely to get in the fluid stream have probably done so, and they will
either end up in the filter eventually and cause no problems, or they
will end up somewhere that causes a problem.

That said, I'll also note that on _my_ hydraulic system, there are no
places teflon tape or pipe dope make any sense at all, as far as I
recall. All the connections I've had to open up are sealed either with
o-rings, or flare fittings - the threads just bring the sealing surfaces
together. Pipe dope might serve as anti-seize, which is no bad thing
(some of my connections took two 3-ft wrenches to open up after being
connected for up to 34 years), but anti-sieze will work just as well.
Your system may well differ and have pipe threads sealing connections.

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