Hydraulic fittings/hoses

SHALER · Jan 10, 2019

When putting hydraulic hoses and fittings together for things like remote hydraulic cylinders, loaders, etc., is it ok to use teflon tape? Or is there something better to use? I thought I may have heard once to not use tape as it can dissolve and get in tractor hyd systems.

rustyfarmall · Jan 10, 2019

Teflon tape is all I've ever used. Never had a problem.

IaGary · Jan 10, 2019

If it is put on the threads properly it cannot get into the system.

johnofnewhaven · Jan 10, 2019

I use Teflon. Just stay back a few threads from the end.

moresmoke · Jan 10, 2019

The official answer is not to use Teflon tape on hydraulics. As others have said, with a little care, you can get away with it.

That said, Loctite 545 is far superior to any Teflon sealant if you can clean the threads before assembly.

Jim.ME · Jan 10, 2019

Tape is not preferred by many, but as IaGary posted it is ok if put on properly. Don't put it out over the end of the threads where it can get cut off inside the fitting when threaded in. A lot of industrial locations do not allow it due to problems with improper installation and bits contaminating their systems. It is common to use liquid or paste type sealants such as Loctite 545 or 567 at industrial locations I have been in. Loctite 51604 Blue Pro Lock Tight Multipurpose Gel Threadlocker will seal and lock fitting and bolt threads if there are vibration problems, but it isn't cheap. Gasoila, Rectorseal, and Blue Magic are some other brands that have good products. With any sealant or tape you need to be sure the grade is good for oils and fuels. Thread sealants are for pipe threads not JIC, compression sleeves, and O-ring sealed fitting threads. If sealing lines for gases (oxygen, propane, etc.) selection is critical. Just my opinion and experience.

Brendon-KS · Jan 10, 2019

As others have said if care is taken during application and assembly the tape will not be in a location that could cause problems. However, if joints are taken apart later there will be tape residue left in the female threads and this could cause issues if not thoroughly cleaned out prior to re-assembly.

jimg.allentown · Jan 10, 2019

Teflon tape, pipe dope, or any kind of sealer is strictly for tapered pipe threads. Sealing the threads on a flare fitting or compression fitting is causing a dangerous situation in the case that the fitting leaks. Just a matter of physics.
On a flare fitting, the actual sealing area is relatively small. Sealing area multiplied by pressure tells you total force on the fitting. Sealing the threads increases the potential sealing area by orders of magnitude. If the intended sealing area were to leak, the total force would increase to dangerous levels.

A rule of thumb is to only use sealer in threads that are intended to seal. Most hydraulic fittings are not intended to have threads sealed.

Mike(NEOhio) · Jan 10, 2019

Use Teflon tape on tapered threads only. Not for O-ring or flared fittings. Wrap it clockwise as you're looking at the end and if you're taping a long thread start away from the end and wrap to two threads short of the end. This is to it doesn't push the tape off as it screws in and no loose ends can get into the fluid. As other have said, it's easier to use a liquid or past type. You can add Blue Monster sealant to that list.

Hydraulic fittings/hoses

SHALER

Member

rustyfarmall

Well-known Member

IaGary

Well-known Member

johnofnewhaven

Well-known Member

moresmoke

Well-known Member

Jim.ME

Well-known Member

Brendon-KS

Well-known Member

jimg.allentown

Well-known Member

Mike(NEOhio)

Well-known Member

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