Stumpalama
Forum Junkie
I think you are good to go. As long as you get a good 6 or so turns into the fitting and the flares are done properly, they will conform to the inner flare and seal up.
Brake Line Flaring - Procedure + Questions (6 Viewers)
- Thread starter RWBeringer4x4
- Start date
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- Thread starter
- #22
Guess we will find out! I have yet to make a flare that I would consider "perfectly uniform" around the outer edge, but they all appear to be pretty level/centered - if the sealing surface is the inner diameter I think I'll be alright.
In the last pic , the flare's secondary step isn't down far enough - hence the lip that formed when installed into the cylinder . I've never heard of any of the fittings on these things being the ISO metric bubble flare , anyone care to clear that up ?
The two bumps from the clamp's frame gap is a non-issue , the tubing will conform to the insert in the female hole when you tighten down the nut . If you want to test a fitting , use a clutch master and an old brake cylinder captured in a vise - just make sure to cover it with a rag to prevent any cracks from jetting brake fluid into your eyes or anything valuable .
Sarge
The two bumps from the clamp's frame gap is a non-issue , the tubing will conform to the insert in the female hole when you tighten down the nut . If you want to test a fitting , use a clutch master and an old brake cylinder captured in a vise - just make sure to cover it with a rag to prevent any cracks from jetting brake fluid into your eyes or anything valuable .
Sarge
- Thread starter
- #24
@Weber Sarge - I definitely don't think these are bubble flares. I'm no expert, but I think the original poster of that comment was incorrect in that assessment. I have never seen any other discussion of bending/flaring hard lines where bubble flares were mentioned for an FJ40. I've only ever seen inverted/double flares.
As for the secondary "step" - you are referring to the inner chamfer created by driving the screw in without the adapter? I'm assuming this just means I need to crank the screw down farther when creating the flare? I tried to get as close to what the original Toyota flares looked like - they also seemed to form a slight lip when screwed down tightly
One way to know if the second step flare is correct - when you tighten down the nut it will only take 1 turn or less to set the line tight , if not flared far enough you'll have to use the nut to finish forming the end of the hard line . If they are centered correctly and don't leak , all is good....
Sarge
Sarge
im helping
.......and learning!!
- Thread starter
- #27
Thanks! Looks like the bubble flares don't have the inner 45-degree angle. So, based on that alone, I'd say Toyota definitely uses Double flares (and, as I mentioned, this is what is maintained in all collective forum wisdom).
That said, the flare nuts I purchased look (a lot) more like the bubble-flare nut, shown above. FedHill claims they can be used for either application (double flare or bubble flare). This may be a completely stupid question - but - does how the back of the flare seats against the nut make a difference? Seems like this could serve as a secondary seal, or something...
That said, the flare nuts I purchased look (a lot) more like the bubble-flare nut, shown above. FedHill claims they can be used for either application (double flare or bubble flare). This may be a completely stupid question - but - does how the back of the flare seats against the nut make a difference? Seems like this could serve as a secondary seal, or something...
Great pics kruisinkid. Rick, in your pics showing the fully threaded Toyota nut, the nut is bottomed out externally before reaching the required depth to seal. Another thing you need to examine closely is that your mix of componenets will most likely have a mix of what flare is required so a line could have a double flare on one end and a bubble flare the other, and yes, there are bubble flares on these trucks. Double flares had a tendancy to split the nut when overtightened making removal a pain.
- Thread starter
- #29
Thanks! I figured that was the case with the fully threaded nut. I'll certainly pay close attention when reproducing these lines, to assure I'm making the correct flare. That said, I do find it surprising that this is the first time I've heard anything, in all my MUD browsing, about bubble flares on FJ40's! If/When I find them as I'm tearing out the old lines, I'll certainly post pictures to confirm, just in case anyone else travels this path!
Exactly where are there bubble flares on these trucks?
Stumpalama
Forum Junkie
I haven't found one, and I've had every hard line apart on both my 40 and 62.
My bad , I remembered doing several bubble flares when replacing my hard lines on my 69 with 9mm fittings. It was actually the BLF-54C adaptors necessary to convert from 9mm - 1.0 male inverted to 3/8-24 female bubble so the trucks didn't have the bubbles, the adaptors did.
- Thread starter
- #33
I haven't found one, and I've seen exactly 2 hard lines off Stumpalama's FJ62. 
Rainman
Wondering what my next vehicle will be...
I too have only heard of the FJ40 having double flares. Also, and please chime in here with other known line nuts on other years, my project is a May '77 and all the line nuts are completely threaded. I tried a shouldered nut and it only threads two rows.
Stumpalama
Forum Junkie
Are you coming down to the swap meet?
- Thread starter
- #36
I'll let you know! I haven't pulled the brakes out of my 40 yet, but the FJ62 brake caliper hard lines I have been messing with had a shouldered nut on one end, and an threaded one on the other. The unthreaded one was absolutely too short to work in my 74-ish clutch master cylinder. The shoulder was required to tighten it down and seal. I still had plenty of thread engagement with the shouldered nuts in the clutch M/C (6+ turns). I'm hoping to dig into the lines soon, then I'll have some definite answers for you!
I'm hoping I can make the drive. I'm mired down in wedding planning, so most of my weekends are booked looking at venues and talking to caterers/photographers/DJ's etc. Fiance is making all the calls but I reserve the power of veto, haha. If I do go, it won't be in the 40 - I'll (hopefully) be putting your knuckles on it by then. I'm getting impatient, but I need to paint, and it's just too damn cold/humid.
Rainman
Wondering what my next vehicle will be...
Okay. Talking to a professional of over 40 years but not necessarily familiar with Japanese lines, he believes there is most likely a difference in the nuts when mated with master cylinders. After our talk, I looked into it and see that the female threads are deeper in the master cylinder than in the drums for instance. So, the reason for the confusion may be that there originally may have been a mix of both. If an FJ40 somewhere in the world still has all of the original lines we just may find out but that may be unlikely. So I would prefer shouldered lines in the deep holes, threaded nuts in the shallower holes.
- Thread starter
- #38
I believe you are right - this is what I found on the FJ62 lines - the nut running into the caliper was shorter, and fully threaded, the nut on the other side of the line was shouldered. Not sure my lines are original (in fact, I am fairly confident that they are not) but I'll pay close attention when they come out!
all of the lines on my '72 were original when I got the truck, and they were double flare
