hydraulic lines to seal

[sp53]

Hi all well I just replaced the clutch master cylinder on my tr3 and the line that goes in the back has a very slight leak. I was trying this morning before work to tighten it down some but could not get a good fit with a wrench. The nut is actually pretty tight. It looks like it needs that famous quarter turn before it breaks. When I get home, I will pull the inspection plate off the back and try and get some more tightening down on it. The line is old and the cylinder is new, so perhaps the flare on the line is not sealing. My question is do people use something like Teflon tape or some other product on hydraulic lines to seal them at the threads. Probably not, I think the seal needs to be metal on metal?

 

[TR3driver]

Nope, definitely should seal metal-on-metal; between the end of the tube and the seat inside the hole. The threads aren't supposed to seal.

That's the low pressure line to the reservoir, right ? I had an original one snap in my hands the other day, with only modest tugging on it; so I would just order a new one.

 

[tomshobby]

Would something like this work?

 

[DNK]

:lol: :lol: Show Off

 

[MGTF1250Dave]

Aloha,

I agree with Randall. A bigger wrench or over tightening will only break something. The seal is metal flare to the flare in the master cylinder. Trying to further tighten the nut may strip the treads. Loosen pipe fitting and the bolts holding the master cylinder in place. This should give you a little wiggle room to see if you can get the metal to metal seal.

Another possibility is some debris may be in the preventing the a good seal being achieved.

If this is the pipe from the reservoir to the master cylinder inlet it does not see high pressure. As a last resort, a small o-ring in the between the pipe flare and the master cylinder will give you a seal. I've done this as a short term fix until I could get a new pipe. DO NOT TRY THIS ON THE HIGH PRESSURE OUTPUT SIDE OF THE MASTER CYLINDER. THE PRESSURE WILL BLOW IT OUT.