Fixed: Brake Master Change Nightmare, thanks to RX1900 (See pg4)

rx1900 said:
Sorry.....I dont agree. I do think...that from the factory....on LHD X1/9s.....the bolts were fed in from the RIGHT side ( that is from the middle of the car ) . As in the above pics. It would seem the intention was to allow you to easily change the clutch master ! As further proof....below are pics from my factory Fiat North America official workshop manual. You can clearly see the nut end of the bolts on the clutch master side. I have no idea how the bolts were fitted on your Aussie RHD cars.......
Click to expand...
well that means the bolts are fed in from the centre of the car in both LHD and RHD versions,

I had always assumed that the bolts coming in from the left on a RHD car was a legacy of the same direction being used on a LHD car... but it appears thats not so! At least on the RHD version you can pull the brake master without taking the bolts completely out.

on a RHD car there is even less room on that side of the pedal box because of the heater tap and heater hoses on that side of the car... and in the early versions even the bonnet release is there in the way as well...so I could never figure out why the engineers would insert the bolts from that side... and it must have been a legacy / carried over from LHD cars, but no,

I guess they made the pedal box easy to drop out because they figured that was the only way to do it.

SteveC
 
I'm beginning to think since no doubt the peddle box was assembled long before bolting to the car, that the bolt direction depended on the left or right handedness of the box assembler that day.
 
So, I get all the parts to "upgrade" my '74 brake master with the new over the top brake line to the junction block and the new brake line to the left front wheel. hooked it all up begin beading and (of course) it starts leaking. From the top of that new/used junction block. I've already tried backing off and re tightening, no joy. I was suspicious of this fitting as the female part did not resemble all of the others in the system. I dread spending another day pulling the whole thing back out now that it's full of brake fluid. Any Ideas? Is there another available double female join that might take it's place?

Block_arrow.jpg
 
BrianM said:
I was suspicious of this fitting as the female part did not resemble all of the others in the system.
Click to expand...
Early cars especially including the ‘74 have a mix of SAE double flares (typical on Detroit iron) and DIN bubble flares (the civilized world) in the plumbing around the master. Look very carefully at every male and female end, look at the flare nuts, make sure you don’t have a mismatch.
The tech info sections at fedhillusa.com will explain all this stuff.
 
I hoped since all of the parts I was installing were late model X, they would all be happy together. Now looking at the flare pictures I have my doubts. Did Fiat change the junction block flares over the years?
 
Steve Thomas said:
Might be the angle of the pic but it looks to me like something is not right with the top male?
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Yes it does look odd. the bolted in block may be messing with the angel. I will free the block rom the bolt and re-seat. Fingers crossed.
P.S. the tiny drip did manage to empty the reservoir overnight. Lucky I had enough towels down to save the carpet.
 
BrianM said:
tiny drip did manage to empty the reservoir overnight
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Well, at least the good news is your supply hoses are not kinked. Brake line fittings are just about the easiest threaded fitting to cross-thread in the auto world. The angle of attack has to be dead on, and most times you are fighting the line flex trying to pull you slightly off course. When you remove and reassemble, assuming nothing is already stripped, and the flares and fittings are correct, take all your tools and put them out of reach. Brake fittings need to be started (by more than a few turns) by hand. Once you have a good start you may need a little more than finger power. I generally use a crowsfoot for this as it's very hard to apply much torque when it's not connected to a rachet. The fitting should go in the rest of the way with VERY little effort. If you feel it binding up at all, stop, back the fitting out and try it again. Once the flare has contacted it's seat, then you can break the tools out to lock it down. If your first install went together with no signs of binding, check the flares carefully. SAE double flares are a little more forgiving than bubble flares, but both can have sealing problems once seated and then removed. If you find a bubble flare end that went into an SAE hole, that fitting is metric. It can be cranked down with some effort, but it will never seal and the line, fitting, and whatever it's screwed into will be damaged. A leak that gravity drains the system quickly is usually caused by a flare not contacting the seat at all, either from a crossed threaded fitting not pulling the flare onto it's seat, or flare type incompatability.
 
Possible mix of SAE 45 degree double flares with Girling bubble flares (common on many European cars from that era and to this day) is due to the US Department of Transpiration mandated requirement for SAE 45 degree double flares or why 74's can have a mix of both tubing flare styles.
It is imperative to verify the type of tubing flare before trying to assemble them or damage to the flares and sealing seat can occur on top of no possible way the tube joint will seal.

This is also why 3/16" OD steel/coated tubing is found on European/Japanese/import cars sold in the US.

Neither SAE 45 degree double flare or Girling bubble flare are designed to be re-sealed, they are designed and intended to be a single use, single assembly tubing joint. This is why extreme care must be taken if they are disassembled then re-assembled. Over torque-tightening of these flare joints is assured damage and greatly increases the possibility of no-seal. The proper fix is to re-flare the ends with new tube nuts, applying anti-seize to the threads and setting them in place with the proper torque.

History of the SAE 45 degree double flare goes back to early hydraulic brake failures and Bundy Weld tubing:
safebraking.com

Why do brake lines rust? and who is this Bundy guy? - Safe Braking

I recently heard a driver ask, “Why aren’t all brake lines made of stainless steel?” The driver asking the question was just hit with a $800 repair bill to replace brake and fuel lines that ran a long a chassis rail on an 11 year old truck. Stainless steel is used on some vehicles, but [...]Read...
safebraking.com safebraking.com
and what kind of flare joint would function with Bundy weld tubing.

Deep dislike for both SAE 45 degree double flare and the Girling bubble flare as neither is designed to be service cycled and designed to not re-seal if taken apart and the joint integrity is not that good. They are and can be the source of hydro leak and similar problems. Given a choice, when ever any brake/clutch hydro system is worked on all related tubing fittings and joints are converted to 37 degree single flare originally as the "AN" spec (aircraft-aerospace) which evolved to become the 37 degree JIS hydro fitting used widely in industry. These 37 degree single flares are designed to be serviced and re-seal if taken apart and are superior to both SAE 45 degree double flare and Girling bubble flare.


The unpleasant task now will be to take the whole pedal box apart and check the junction block for tubing flare style/type and address this problem first. Second will be how to deal with the likely damaged flared tube ends and junction block. Know even the smallest imperfection in the flare joint's sealing surface will produce a no-seal and leak.

Report back with pictures and findings of what is going on with the leaky junction block.


Bernice
 
Steve Thomas said:
Step through these images to clarify what you will see with each type. http://www.fedhillusa.com/?page=flare
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Great page for telling the difference. I remember now that the junction block was definitely DIN Bubble. While the break master was SAE Double. I'll have to take a look it at the crimp ends when it's apart to see what the line crimps are. Just a guess but it seems odd that the over the top long line from the master to the block would have one style crimp on the master side and and the other style crimp on the block end???
Maybe I can swap out the block for just a double female fitting.
What is the thread size for the break line fittings? Anybody know off the top of their head, and save me trying to measure under the dash :)

EDIT - Found the thread on MB. M10X1.25 on a 3/16 brake line.


Thanks, this is a great thread.
 
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BrianM said:
I remember now that the junction block was definitely DIN Bubble. While the break master was SAE Double.
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Are you sure your memory isn't playing tricks on you? I just had a look at my old brake master cylinder (removed from my '85), and it is definitely set up for bubble flares. Both Midwest-Bayless and Fiatplus show that the master cylinders from beginning through end of production differed in the inlet ports only,
 
I reckon that little length of tube from the block union to the master is dodgy - not an original FIAT part. The short tube goes with the union so them having different fitting types is not believable if they are both genuine parts. I would guess somebody made that short tube from a longer one and guessed wrong on the fitting...
 
ng_randolph said:
Are you sure your memory isn't playing tricks on you? I just had a look at my old brake master cylinder (removed from my '85), and it is definitely set up for bubble flares. Both Midwest-Bayless and Fiatplus show that the master cylinders from beginning through end of production differed in the inlet ports only,
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It's possible. I'll check my old one.
 
It can be a little difficult to make bubble flares properly (compared to the more common SAE flares). So they have much more propensity to leaking. Often remaking it again solves the leak. However it would not surprise me if the line had two different types of flares on it....that's the sort of thing they might do back then. Also, the bubble flare nuts used on the X are not common at all....even for bubble flare nuts. There's only a couple of good sources to get them so make sure you have everything you need before cutting things.
 
Steve Thomas said:
I reckon that little length of tube from the block union to the master is dodgy - not an original FIAT part. The short tube goes with the union so them having different fitting types is not believable if they are both genuine parts. I would guess somebody made that short tube from a longer one and guessed wrong on the fitting...
Click to expand...
There are 3 tubes. 2 go to the brake balance warning light switch (short, medium) and one goes to my leaky junction block (long) MWB lists them all the same although their nomenclature is different. sometimes ISO bubble flare, sometimes European bubble.
I'm starting to think I just screwed the damn thing in crooked.
 
Dr.Jeff said:
It can be a little difficult to make bubble flares properly (compared to the more common SAE flares). So they have much more propensity to leaking. Often remaking it again solves the leak. However it would not surprise me if the line had two different types of flares on it....that's the sort of thing they might do back then. Also, the bubble flare nuts used on the X are not common at all....even for bubble flare nuts. There's only a couple of good sources to get them so make sure you have everything you need before cutting things.
Click to expand...
I have a flare tool from back in my Europa days. Just need to check which flare...
 
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