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| | | | Joined: Jan 2013 Posts: 1,384 Shop Shark | | Shop Shark Joined: Jan 2013 Posts: 1,384 | Just redid the brake lines on the 48 2 ton in the process of installing the front disc kit.
Because the master is mounted below the calipers and wheel cylinders and the new master has one of those big plastic covers that I don't have a power bleeder adapter for, I started by vacuum bleeding.
Got the system full only to find some leaking connections.
I honestly can not remember ever forming a flair connection that leaked.
All the fitting blocks are the original parts, brass, cleaned and inspected.
Cu Ni line that I have used before on at least 1 brake system as well as compression and AIN fitting applications.
And I can't really see why new flair nuts ("product made in USA, China or Korea") would cause the leaks.
These are single flairs, never owned a double flair tool.
In the morning when I'm in a better mood, I will cut one of the flairs off, clean up some of the flair nuts from the original line and reflair the line. If it still leaks, that will eliminate the nuts.
Has anyone else been running into this problem? | | | | | Joined: Nov 2006 Posts: 2,544 Shop Shark | | Shop Shark Joined: Nov 2006 Posts: 2,544 | Brake lines always require a double flare to seal | | | | | Joined: Mar 2002 Posts: 9,115 'Bolter | | 'Bolter Joined: Mar 2002 Posts: 9,115 | I didn't think single flares were ever used in brake systems. | | | | | Joined: Sep 2001 Posts: 581 Shop Shark | | Shop Shark Joined: Sep 2001 Posts: 581 | Jim,
I suspect I'm not teaching you anything when I say that the flare tool has to match the seat, and there are 2 common sizes: 30 degree, and 45 degree (or is it 40?) Anyway, if you, like me, own several different flare tool kits, you can grab the wrong one or use the wrong side, and have mis-matched flares.
I agree with Don, though, that brake lines always use a double-flare. Brake line flare kits are available from most FLAPS. Or borrow one.
-Michael | | | | | Joined: Jan 2013 Posts: 1,384 Shop Shark | | Shop Shark Joined: Jan 2013 Posts: 1,384 |
Wrong tool. It was on the bench because I had just done some AIN flairs.
Last edited by cletis; 03/16/2015 5:14 AM. Reason: language
| | | | | Joined: Jan 2013 Posts: 1,384 Shop Shark | | Shop Shark Joined: Jan 2013 Posts: 1,384 | It's very rare for me to do a vehicle with hydraulic brakes, Strange as that seems.
A friend had the tool for the last one. Totally forgot and just picked that one up. | | | | | Joined: Sep 2001 Posts: 581 Shop Shark | | Shop Shark Joined: Sep 2001 Posts: 581 | What . . . more of an air-brakes man?! Different beast all-together, isn't it?! Or do you tend toward the older, mechanical brake stuff?! THAT will test your skills, for sure! I think air is probably easiest and most trouble-free, hydraulic after that, and then mechanical. Of course, if bell-cranks and rod-straightening are your thing, then mechanicals are for you . . . ;-)
-Michael | | | | | Joined: Jan 2013 Posts: 1,384 Shop Shark | | Shop Shark Joined: Jan 2013 Posts: 1,384 | The restorations are mainly mechanical. Farm tractors and early cars/trucks.
Having a class 1 most of the road time in big stuff was air. | | |
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