compression fitting on nylon clutch line?

[montanaman]

- '91 xj,
- 4.0 HO
- AX15 with internal slave
- Nylon clutch line with "quick disconnect" which won't disconnect.

HERE IS MY STOCK ARRANGEMENT:

HERE ARE THE CHANGES I WANT TO MAKE:

I want to upgrade the nylon clutch line & quick-disconnect with a metal brake line and threaded coupler to attach the new metal MC line to the slave line. Advanced Adapters sells a kit for just this scenario, but they charge $75+ for it. I'd prefer a home-brew solution.

The problem is how to attach a metal brake line to the Master Cylinder. The MC doesn't have a threaded outlet ... the nylon line pushes into a smooth hole and is held in place with a roll pin.

I'm thinking to save about 2 inches of the nylon line where it comes out of the MC, and somehow connect that cut section of nylon to a metal brake line.

Any good ideas how to do this? Has anybody used a compression fitting in this situation? Would it work? I can get a compression fitting that adapts to 1/8" NPT, then convert the NPT to metal brake line and be good to go. But I don't know if a compression fitting would work properly with this kind of nylon line, or even if I could find it in the right size.

Or how about a barb fitting with some kind of special adhesive and a clamp? The metal adapter that pushes into the MC seems to be fitted to the nylon line with a barb.

Any other ideas?

Thanks.

 

[tbburg]

No experience with nylon in hydraulics, but for domestic water(50-75 PSI) using compression fittings, we usually install a metal sleeve into the end of the nylon hose to prevent the line crushing as the ferrule compresses. I'm pretty sure I wouldn't want that setup on my clutch.

Probably the simplest solution would be to cut the quick connect adapter off the slave cyl. line, then get a flare tool and press a 45deg. double flare on the end of the line. They you can just use a female-female coupler, and take off straight from there with 1/8" hard line. The only problem with that is you have to mod the slave cylinder, making replacement a bitch.

If you want to keep the quick connect, I'd say braze or solder a hard line into the back of the coupler and do away with the nylon entirely. Brazing is a lot stronger, but silver bearing solder will work while using a lot lower heat(also strong enough for 300 PSI in an AC unit)

 

[montanaman]

I do not want to keep the quick disconnect. Getting rid of it is easy.

The pic above is not very clear, but it shows the connection down by the tranny bell housing. The smaller line going to the left goes to the Slave. The heavy black line goes up to the MC. If you look closely, you can see that the disco will simply unscrew from the slave line and leave a male threaded brake fitting on the end of the slave line.

And getting a female-female coupler is no problem either. So I can run a metal brake line all the way up to the MC.

Everything is easy until you try to attach that metal brake line to the MC ... how to attach a threaded brake line to an MC that doesn't have a threaded output port?

 

[montanaman]

Ok ... I found a really easy solution. The 1990 xj has an MC with a threaded connection. And the the '90 stock clutch line is a traditional hydraulic line with threaded brake fittings on both ends. I found a new '90 Bendix MC for $19 bucks at a store going out of business, and the hydraulic clutch line was $15. Now I just need a $2 brake line Union (to replace that disco) and I'm good to go.

Very cheap ... AND I have a new MC now.

 

[tbburg]

Glad to see you found a solution.

Re-reading your post, I see I missed the reference to the MC. I looked at the pic and assumed you were talking about keeping the bottom end of the line. Bone-headed move on my part there,..

 

[montanaman]

Thanks for your replies tbburg ... is one of the best forums around.

When I get that union coupled up down by the tranny, I'm going to coat it in grease and seal it up in some heat shrink. Then next time I need to disconnect my clutch line, I'll have no problems. Cut the heat shrink away, wipe off the grease, and you'll have virgin hardware to work with.