Leaking brake line fittings (1 Viewer)

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JDNs78FJ40

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Dec 3, 2018
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Location
Draper Utah
I had everything hooked up and was going to bleed the brakes and noticed most of the fittings, if not all of them were leaking. Even the fittings that came on the brake lines I bought from Cruiser Corps. I hope I just need to loosen and re-tighten and repeat a few times to get those to seat. I feel the double flares I did to plumb in the Wilwood P-Valve with the titan tool were pretty good. I bought some 3/8 male fittings to connect the proportioning valve to the system and wondering if the leaks in this area were due to the wrong fitting. The original fittings (M10x1.00) are not fully threaded and are longer than the ones I bought. Could that be my problem at the proportioning valve? As far as the others, is it just a matter or tightening them, but not too tight?

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I would try tightening a bit more and see what you come up with. Use a flare wrench to do this...DO NOT use a regular wrench.
 
I would try tightening a bit more and see what you come up with. Use a flare wrench to do this...DO NOT use a regular wrench.
Thanks John. Seems like there is fine line between too tight and not tight enough. I just ordered a metric brake line wrench kit. Hopefully that is the trick.
 
I have had issues with those brass types were the threads go all the way down but get yourself a flare wrench and use a vice grip to make sure it stays closed and you should be able to tighten it way up.
 
The SS fittings that came on my brake lines from cruiser corps seem to be different than the brass ones I bought and the fittings that were in my original brake lines. The originals and the brass ones are indented?
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I think trollhole meant the flare on the tube itself. The pic makes it look more like a bubble than inverted.
 
Skreddy is correct, it's the double flair of the tube that makes the seal. The fittings are not pipe threads. When I double flair metric, I make the bubble, then complete the secondary flare but I don't crank it down hard. I finish it with the install of the line into the fitting. I think, I read somewhere on this site, that SAE double flares are at 45* and metrics are slightly different. If they leak and the flair looks correct and centered then I just tighten it down a little more to stop the leak.
 
In addition to using proper metric sized flare wrench, best to make sure your fittings are the proper metric ones. If memory serves, it should be 10m x 1.0 for the later models. I always save the toyota flare nuts as they have that nice extended leading edge, but I have gotten decent ones from a hydraulic hose shop. I have never had one of those leak. You don't really need to crank down HARD on them, only good and snug to get a leakfree seal.

Get a quality tubing flare kit. You won't want to spend the bucks on a MasterCool kit as I did, but they are out there. Eastwood has a nice vice-based kit, but still not cheap. Cheap ones will only give you lopsided flares... You'll want a quality tubing cutter as well, and decent tubing bender(s).

As a suggestion, when you take closeup pics, set the camera on macro to avoid the fuzzies.
 
the issue is with your flare nuts,
and more importantly, the collar on the end of the flare nut (OEM is extended leading edge - as mentioned above)

all 10m x1.0 are not the same.

thankfully no one has referred to a bubble flare yet!...
 
the issue is with your flare nuts,
and more importantly, the collar on the end of the flare nut (OEM is extended leading edge - as mentioned above)

all 10m x1.0 are not the same.

thankfully no one has referred to a bubble flare yet!...
The flaring tool I bought was a titan 3/16 double flare tool that other members have reccomended.

I agree with you on the fittings and this was my concern. The wilwood p-valve I bought from another member came with these adapters that go in the actual valve:

Fitting Angle:Straight

Fitting Attachment 1:Female threads

Fitting Size 1:3/8-24 in. inverted flare

Fitting Attachment 2:Male threads

Fitting Size 2:1/8 in. NPT

So, that is why I bought the 3/8-24 male fittings to go on the brake lines coming in and out of the p-valve. All of the other fittings are 10m x 1.0 that were on the brake lines I bought. Do you think I'm okay using the 3/8-24 fittings that are full thread and don't have the leading edge or do I need to track some down?

Thank you all for the input. Definitely a learning experience and one I would hire out next time.
 
the 10m x 1.0 that you bought on the brake lines are not quite the same as OEM toyota, the collar is too short.

the p valve has different flare nuts all together. 3/8- 24? - (take a mic/look at what you're putting the flare nuts into and replicate with profile of flare nut)

its definitely a learning experience and it is a pretty common curve.
once you do it once and figure it out that 10m x1.0 are not all created equal, no need to hire it out to have someone else learn on your dime.

at this point you are one proper toyota flare nut I.D. away from being a land cruiser flare nut expert

your flares look good enough; as mentioned in this thread, don't over flare, let the nut seat the flare.



if you need pics, the good and bad examples are both on my shop bench.

if your local supplier "can't or won't" get the appropriate flare nut, amazon sells packs of ten.
 
Reviving an old thread as I was having the same problem and wanted to add the solution I found. I bought stainless steel brake lines from cruisercorps and the 2 lines to the rear wheels were leaking. I tried reseating and tightening again but it didn’t help. I contacted cruiser crops but they said I over tightened causing the leak. What I have since figured out is the brake line fittings that they used were too short. I think this picture would be helpful for anyone trying to buy fittings as there are many 10mm x 1.0 that do not fit. The fitting on the left is what I needed.
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