I need a brake/clutch/fuel line flaring and fittings 101 class please

[shark92651]

I am getting close to needing to run my hydraulic lines for brake/clutch and my fuel line. I'm a little confused on the fittings and the flare types so please could someone help me to understand?

Should I use the same 3/16" line to run to my hydraulic clutch slave as I would use for the brakes?

When looking at fittings, is an "inverted flare" the same terminology as "double flare"? For instance I need a fitting that will connect the hard-line to my Tilton master cylinder. The specs for the Series 76 master cylinder show that it has an AN-3 outlet port. So I assume this means I need an AN3 male on one end, but what is needed on the end that connects to the flared tube? I haven't looked yet, but I assume my kit already includes the fittings to connect the hard line to the Wilwood master cylinders, but the Tilton for my clutch didn't come with any for either the output or the low-pressure, so need to know the correct size and terminology so that I can order what I need.

For the 3/8" hard fuel line, I assume a double flare is needed there as well. What sort of fitting would go on that? Is it the same as the brakes, just larger?

Any other useful tips would be appreciated. I am going to use Nicopp line and I have access to Eastwood tube straighteners and the Eastwood flaring tool so the actual bending and flaring shouldn't be too much of an obstacle, I hope!

[edwardb]

Responses:

- You should use a flex line to your hydraulic clutch slave. Not the same 3/16 rigid line as your brakes. Typically the clutch slave has -AN fittings. You should be able to get a pre-made flex line for the hook-up.

- A double flare can either be an inverted flare or a bubble flare. So kind of the same thing but can be different. Inverted flares are pretty much standard on this side of the pond, and what I would expect you'll be doing. I don't recall seeing bubble flares used on these builds. Google the terms and you can see the difference.

- SAE inverted flares are 45 degrees. AN fittings are 37 degrees. Don't mix them up. If the Tilton master cylinder is -AN, use only -AN style fittings. Note you can get a 37-degree turret for the Eastwood flaring tool. I have the Eastwood flaring tool but have never used if for anything other than the common 45 degree variety. All -AN fittings I've purchased.

- Yes you can put 45 degree inverted flares on 3/8-inch fuel line. The tube nut is similar to a brake line, just bigger (obviously). The Eastwood flaring tool has 3/8-inch tubing capability.

- Just follow the Eastwood instructions. That Nicopp line will flare like butter with that tool.

Good luck!

[NAZ]

If you're not sure by looking at the M/C outlets what type of fitting they use you should contact Tilton. They may be a banjo style that requires sealing washers or they may be set-up to use SAE inverted flare or both. If you look at a female SAE inverted (sometimes called double) flare brake line fitting you will see a cone shape at the bottom of the bore that mates with the tubing flare. If you have an SAE inverted flare fuel fitting it will have that same conical shape and an SAE inverted flare tubing nut will easily thread into the fitting.

BTW, dash sizes are measured in 1/16" increments so a -3 AN is referring to a 3/16"tubing size. Just because there is a dash size call out doesn't necessarily mean the port accepts 37-deg AN /JIC hose ends directly -- you may have to purchase an adapter fitting if you want to use an AN hose end to run a flex line from your M/C to the slave cylinder. Same thing on the slave cylinder -- check the inlet bore.

[shark92651]

Responses:
- You should use a flex line to your hydraulic clutch slave. Not the same 3/16 rigid line as your brakes. Typically the clutch slave has -AN fittings. You should be able to get a pre-made flex line for the hook-up.

The specs for the Tilton release bearing show that the short flex lines that are on the release bearing are AN-4. I was thinking to run a hard line from the master down near the transmission and then use a union fitting to go from the hard-line to the AN4 flex line at the transmission. Are you suggesting that a flex line from the master all the way to the flex on the release bearing may be the way to go? Is there any concern that a long run of flex line may make it feel spongy?

If you're not sure by looking at the M/C outlets what type of fitting they use you should contact Tilton. They may be a banjo style that requires sealing washers or they may be set-up to use SAE inverted flare or both. If you look at a female SAE inverted (sometimes called double) flare brake line fitting you will see a cone shape at the bottom of the bore that mates with the tubing flare. If you have an SAE inverted flare fuel fitting it will have that same conical shape and an SAE inverted flare tubing nut will easily thread into the fitting.

The Inlet port for the Series 76 master cylinder shows as AN-4 and the outlet is AN-3, dual outlets one on back and one on top (does this mean I need an AN-3 plug for one of them)

Here is Tilton 76 Series spec sheet:
https://tiltonracing.com/wp-content/..._76-Series.pdf

I was planning on buying this for the hose adapter to my reservoir: https://www.summitracing.com/parts/fra-484104-bl
Good choice?

If I go flex line all the way to the release bearing I guess I just need an AN-4 hose and a AN-4 to AN-3 reducer on the master side and an AN-4 male union on the release bearing side. I hope I'm getting this correct and not over-complicating it.

[NAZ]

The web site info indicates there are two -3AN size outlet ports and a -4AN inlet so again, you need to determine what thread the ports are using and if they are configured for banjo fittings, SAE flare or both and go from there with your fittings. And yes, one will need to be plugged. There is not enough info on their web site for me to determine with certainty how these ports are configured.

As for running your juice line to your slave cylinder it's your choice if you want to run all flex (sometime simpler) or a combination of hard line & flex. Since you have a -4AN fitting on the slave cylinder I suggest you run all -4 line to the slave cylinder. Juice clutches are slower to operate than mechanical and thats because of the size ports and line used is so small. Not sure if it will help at all or if it does, how much but if nothing else, the smaller the AN hose the harder it is to work with.

[Fixit]

A few tips for flaring lines (regardless of tool used):
- PRACTICE... buy a length of tubing and practice cutting, deburring and flaring. Get to know the tool and how it performs before working on your "finished" pieces.

- The raw end of the tubing must be square & deburred. The tubing cutter will leave a tapered edge, and a ragged inner diameter. Clamp the line in the fixture and give it a few strokes with a fine-tooth file so the end is square & perpendicular. The finished result should be a nice circle with just the wall thickness of the tubing showing.
- After prepping the end (above), blow out the line with air, or flush out with carb spray/brake clean etc.
- SLIDE YOUR FITTING ON THE TUBE! I can't count the times I've made the perfect flare, and then DOH! No Fitting. Cut it off and try again.
- Use some brake fluid as a lubricant on the flaring cone & die.
- Don't go gorilla on the flaring process. It doesn't take a lot of effort to make the flare.

[chmhasy]

Here is the one I had good luck with

cal-van tools 165 master inline flaring kit

https://www.amazon.com/Cal-Van-Tools.../dp/B00AOTBVJQ

https://vimeo.com/110589693

[edwardb]

The specs for the Tilton release bearing show that the short flex lines that are on the release bearing are AN-4. I was thinking to run a hard line from the master down near the transmission and then use a union fitting to go from the hard-line to the AN4 flex line at the transmission. Are you suggesting that a flex line from the master all the way to the flex on the release bearing may be the way to go? Is there any concern that a long run of flex line may make it feel spongy?

Well, first I wouldn't worry about it being spongy with SS flex. It's really not all that far and the line pressure in a hydraulic clutch is considerably less than brakes. On the Roadster, I go from the MC straight across on the 2-inch dash tube, through the inner footbox panel, and right to the slave. It's in the 30 inch range, as I recall, but don't quote me on that. I've done two Forte setups that way, which I think are AN3. Works fine and certainly not spongy. But having said that, I was forgetting the fact that you're using the Tilton HRB, and it already has flex lines. One for the bleeder and another for the line to the MC. If it sticks out of the bell housing enough to clear everything including slight engine movement, probably would be fine to use hard line direct to the Tilton flex. Hadn't thought of that to be honest.

[Ray]

Here is what I know about flaring brake/fuel lines:

Flare.jpg

Ray

PS: https://www.eastwood.com/professiona...ring-tool.html probably the best flaring tool.

[shark92651]

Well, first I wouldn't worry about it being spongy with SS flex. It's really not all that far and the line pressure in a hydraulic clutch is considerably less than brakes. On the Roadster, I go from the MC straight across on the 2-inch dash tube, through the inner footbox panel, and right to the slave. It's in the 30 inch range, as I recall, but don't quote me on that. I've done two Forte setups that way, which I think are AN3. Works fine and certainly not spongy. But having said that, I was forgetting the fact that you're using the Tilton HRB, and it already has flex lines. One for the bleeder and another for the line to the MC. If it sticks out of the bell housing enough to clear everything including slight engine movement, probably would be fine to use hard line direct to the Tilton flex. Hadn't thought of that to be honest.

Paul do you have a photo of where your clutch line is routed? I saw a pic on your thread that shows your flex line coming out the back of the master and heading towards the PS, but didn't see where it exits into the trans tunnel area.

[edwardb]

Paul do you have a photo of where your clutch line is routed? I saw a pic on your thread that shows your flex line coming out the back of the master and heading towards the PS, but didn't see where it exits into the trans tunnel area.

Nothing too great I'm afraid. Sorry. I have this one showing the flex line leaving the clutch MC and going down the 2-inch dash tube. It exits in the corner of the inner footbox panel. In the same corner as where the rear harness usually is routed, if that helps. Straight shot from there to the clutch area. Hope that helps a little.

[shark92651]

Nothing too great I'm afraid. Sorry. I have this one showing the flex line leaving the clutch MC and going down the 2-inch dash tube. It exits in the corner of the inner footbox panel. In the same corner as where the rear harness usually is routed, if that helps. Straight shot from there to the clutch area. Hope that helps a little.

Yes, thank you.