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TR4/4A MOPRED Univesal Flares

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TBU_Triumph

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Seasons Greetings to all!

The 1966 TR4A project continues to challenge my 50+ years of engineering and automotive mechanical skills and experience!

The owner bought a complete set of hard lines and fittings from Moss Motors. Yesterday I was checking the system for leaks with a low pressure air source (15 psi) through a bleeding adapter on the master cylinder. It would not hold that pressure so I started working through the system. I finally gave up in frustration when I determined that every fitting on the 4 way junction at the front was leaking. It is very obvious that every port in the 4 way fitting has a concave seat and the end of each tube is a concave seat.

Based on information on the Moss website the brake line flares are the "universal" design produced by MOPRED that will magically work with any style fitting (37 or 45 internal or external cone). Of course a call to Moss generated the standard "on one else has that problem" response.

So what are the secrets to making these seal? I assume I am missing something obvious.

Thanks for the help!

Rusty
 
Only two solutions IMO. Either cut off the wrong flares and put the right ones on; or buy lines from someone else. Also make sure you have Girling pattern nuts with the extended tip.
THIS
britishg316.jpg


NOT THIS
A24.1.jpg


Fedhill has the nuts (and other components) at a reasonable price and none of that "one size fits none" stuff.
https://store.fedhillusa.com/britishgirling-316475nutsandfittings.aspx
 
For what it's worth, I installed one of those "universal" brake lines from Moss this past summer. It was going from the master cylinder to the five way (TR3A) junction. I have not experienced any problems. Everything worked as advertised.
 
1966 was a long time ago. Could someone have changed the 4 way to a generic fitting and the new lines are designed for the original fitting.
 
This thread has me thinking... and I will report back when I take a look in my garage.

I just ordered new brake lines from Classic Tube and a new four-way fitting from Moss. I am not sure what type of flare is used by Classic Tube - and if it matches the 4-way union. I will check and report back...
 
Thanks to all for the responses.

That is a good point to check the 4 way fitting.

I am also interested in what flare is on the Classic tubes. Remember that where a hard line connects to a hose end might need to be a double flare on the tube.

In this situation it is a new 4 way also from Moss Motors. I did confirm that it has concave seats for all 4 ports.

Based on what I can determine the idea with the "universal" flare is that there should be a line of contact somewhere along the radius where the double flare folds back on itself and the concave seat in the fittings.

I am going to try these tricks when I work on things again in about a week.
1) Confirm the nuts have the extended tip.
2) Trial fit everything to confirm that the nuts do not bottom before clamping the flare and that the tube flare is centered in the fitting.
3) Lubricate both the parts with brake fluid before assembly.
4) Make sure I properly back the joint so I can get it tight.
5) Hope it works!

Rusty
 
There's something here I don't understand. I can see how it would be possible to make a universal fitting that would work with either 45- or 37-degree flares, but I can't see how a fitting could handle both a conical and a bubble flare. So, if you lines have bubble flares, and the fitting is made for 45/37 conical, I think you're gonna have leaks, no matter what. The solution would be to reflare for 45 degrees or get a junction designed for the bubble flare. Unless I'm missing something.

Fedhill has four-way junctions for specific flares; for the bubble, see https://store.fedhillusa.com/p193br.aspx.
 
I had my doubts too but the illustration on the Moss site shows the intent of the design.

MOPROD Universal Flare:
hydralic_piping_2a.jpg


hydralic_piping_3.jpg


It appears the contact is more like a bead than a matching angle for concave or convex.
 
Ah, OK, thanks, I misread. I thought the universal part was in the four-way junction, not the flare itself.

It is an interesting idea, but it does make me think of one of my favorite comments: the world is full of good ideas that don't work. But, work or not, it seems to me that the advantage of this device is mainly to the supplier, who needs to stock only one type of item and can sell it to everyone. It's not a benefit to me. I see no disadvantage in having to use a particular family of fittings and flares.
 
Hello to all,

I do appreciate all the responses and discussion. Unfortunately this is not giving me the confidence I was hoping to receive. I was hoping there was a "silver bullet" that told me how obvious the solution is or that I was missing something very simple.

There have been over 250 views with responses from 5 people. Only one of them reported success with the universal design.

I will let you know in a few weeks if we are successful.

In the meantime, enjoy the holidays!

Rusty
 
Rusty,

I apologize for not inspecting the Classic Tube flare as promised - we have company visiting (the kind I like to spend time with :smile: ) and I have not been in the garage in the past few days! Visually, the flares look like Randall's first photo, i.e. the "correct" flare.

Do you know the source of the new 4-way valve? If the tubes are Moss, and the 4-way is from Moss, you might be well served to call them up and ask why things are leaking?
 
Hi Mike,

Thanks for the confirmation that Classic is providing the correct style flare.

Yes, we did call Moss. I noted in my original post that we received the "no one else has this problem" answer.

In fact that is why I initiated the post. My assumption was that if no one else had the problem I have missed something. I assumed that lots of people buy these style brake lines and fittings from Moss and use them successfully. Unfortunately that is not what I am hearing.

Rusty
 
TBU_Triumph said:
My assumption was that if no one else had the problem I have missed something.
Click to expand...
I have a different assumption when Moss says that.

True story: Years ago, I was learning the hard way that the spin-on oil filter conversion that Moss sells does not fit early TR3 motors with the bypass style oil filter head. (Yes, their catalog/web site says that now, but it didn't then.) After over a year of frustration, I figured out the problem on my own, and took the relevant parts to their counter in Goleta to educate them. Mind you, I had already returned the kit twice because it didn't fit, and called several times to discuss the problem. I also had with me both types of filter head and the conversion kit, to make it clear why it wouldn't fit. Guess what the counter droid said to me? (Without learning who I was, so he had no way to know it was _I_ that had been complaining for over a year!) He didn't even look at my little show and tell.

And, they still didn't fix the catalog, "because no one has ever complained". They did eventually fix it, after I started telling everyone that Moss was selling a part that could not possibly fit. Their buyer even got mad at me for not telling him before telling the world. Then the very next catalog edition got changed back, because their supplier (MOCAL, not MOPROD) had the wrong information as well.
 
Hi Randall,

Thanks for the reaffirmation that there is a basic problem that Moss is ignoring.

I will not dispute that you can use engineering drawings to show how the universal flare will seal in multiple configurations if the flare and fitting are perfect.

My years in equipment design and manufacturing have clearly taught me that such assumptions are setting you up for failure!

Rusty
 
In theory, theory and practice are the same.

In practice, they are not.
 
TBU_Triumph said:
There have been over 250 views with responses from 5 people. Only one of them reported success with the universal design.
Click to expand...

And other then yourself, only one person (myself) has even reported using the universal design. Maybe I got lucky. Maybe a lot of others on this board have installed them without realizing they were using "universal" brake lines. I'm sure if others on this board had problems they would have piped up about it.

It may not be the perfect solution, but in my case so far, it has worked out just fine. We'll see over the long haul.
 
Hi Art,

My hope was to hear from all those people who had success with lines from Moss and this design. Yours was the only response of that nature.

We will see what happens next week.

Thanks for the link.

Rusty
 
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