What brake flare do I need to get?

Messages
258
Location
Western NY
So I've got a 2005 Kia Optima 2.4l LX. I asked this over at kia-forums.com but no answered yet. Hopefully you guys can help me out smile This weekend it's brake line time. I've never made a flare before so I'm leaning towards pre-flared PolyArmour lines from AGS, stuck together with unions. I've heard it can be tricky to make flares, and the pre-flared lines seem like a good way to avoid them altogether for only a couple of bucks more. How do I know what flare type I'm going to need to fit my master cylinder and brake hose connector? I see there's three types for sale - ISO bubble flares, SAE invert flares, and Japanese invert flares. I think the Japanese and SAE are the same, but one with SAE nuts and one with metric nuts (?). I do have a replacement brake hose. From looking into it, it looks like the picture of the cut-away ISO/Bubble flare connector here ( http://store.fedhillusa.com/flare.aspx ). Would that mean the whole system is bubble flare? Is it possible to identify the flare type just by looking into a connector like that? I'm using a friend's shop and I don't want to bug him for rides around during the repair, so I'm trying to get the right stuff all lines up before I head over there. If somebody knows for sure how I can figure this out (or if you've done brake lines on this car and just know), I'd appreciate the info! Thanks!
 
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4,437
Location
Guilford, CT
Originally Posted By: Smcatub
I do have a replacement brake hose. From looking into it, it looks like the picture of the cut-away ISO/Bubble flare connector here ( http://store.fedhillusa.com/flare.aspx ). Would that mean the whole system is bubble flare?
No. It's common to have several different types of flare and thread size on a car.
Originally Posted By: Smcatub
Is it possible to identify the flare type just by looking into a connector like that?
Flare type, yes. Thread size, no. You might be able to find out thread size by looking up the parts online. Example: I looked up a front brake hose for your 2005 Optima and the product description says it has a 10x1.0 mm thread size: http://www.napaonline.com/Catalog/Catalo...2429_0282889946
 

Smcatub

Thread starter
Messages
258
Location
Western NY
Originally Posted By: exranger06
Originally Posted By: Smcatub
I do have a replacement brake hose. From looking into it, it looks like the picture of the cut-away ISO/Bubble flare connector here ( http://store.fedhillusa.com/flare.aspx ). Would that mean the whole system is bubble flare?
No. It's common to have several different types of flare and thread size on a car.
Originally Posted By: Smcatub
Is it possible to identify the flare type just by looking into a connector like that?
Flare type, yes. Thread size, no. You might be able to find out thread size by looking up the parts online. Example: I looked up a front brake hose for your 2005 Optima and the product description says it has a 10x1.0 mm thread size: http://www.napaonline.com/Catalog/Catalo...2429_0282889946
Thanks! I looked up the spec for my master cylinder and it's M 10x1.0. Maybe the parts store will have one in stock I can take a look at before I buy my lines.
 
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36,461
Location
ME
Whatever you do, don't stick a 3/8" nut in a hole for 10mm X 1.0. It'll fit and even seem to thread in but is slightly too small and will pop out later. NAPA has "master cylinder adaptors" as some MCs have 4 different ports for 4 different wheels, so they aren't mis-done at the factory. It doesn't make sense to stock every kind of line-plus-nut-plus-flare combo. If you're lucky these adapter nuts are color coded. These adaptors are expensive but keep you from flaring. They're also slightly more "sloppy" looking and are another failure point.
 
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1,427
Location
NY
Buy premade prebent lines and call it good or buy a flaring tool and some line and fittings and do it yourself. Its very easy. If you do flare it yourself please remember to put on the fitting before flaring.
 
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6,388
Location
Washington St.
37°, 42°, or 45°? (Probably not 37°.) Did Kia use Japanese DIN/ISO specs or European DIN/ISO specs for their flares? Buy the lines pre-made for your car.
 
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25,943
Location
MA, Mittelfranken.de
Your local AA should have everything you need in stock and rent you a flaring tool. You want to us NiCopp lines, AA has them in stock as well as the fittings. Take the old fittings and a piece of line down with you. NiCopp bends and flares so easy it makes doing drake lines a snap even for the DIY. Remove the old one as complete as possible and bend it the same shape. practice a couple of flares off the car on a short piece, use a mini tubing cutter. Be sure to lube the flaring tool with brake fluid, it make a much nicer flare, don't forget to put the fitting on first. LOL NAPA also has a lot of fittings, no need for pre bent steel lines, this stuff will last forever.
 

Smcatub

Thread starter
Messages
258
Location
Western NY
Yeah, as far as I can tell there's no such thing as pre-bent lines on this car. So that idea is out. It's what I would have liked to do, but I can't find them anywhere. I didn't look at the dealer - I just assume they'd cost way too much. After reading all of your advice I think the plan is going to be: Buy 25' of AGS Ni/Cu line, a five-pack of each type of nut, and a union for each type of flare. I'll brake the flare tool and hopefully get good flares (thanks for the brake fluid lube trick, I'll do that). The unions are in case I kink the line; I can just cut it and put in a union so I won't have to re-do too much work. The Ni/Cu line looks easy to work with, so hopefully I won't need the unions. Then whatever I don't use goes back for a refund smile Thanks everyone
 
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Messages
25,943
Location
MA, Mittelfranken.de
Its real easy to bend and work with just be careful of tight bends with any line unless you have a good bending tool. You can bend this stuff nicely over a piece of 1" plastic pipe and get a good bend out of it. Once you use this stuff you will never use steel again, i guarantee it. It will never rot, so its perfect for road salt environments, OE on Aston, RR, Volvo, Porsche, etc. I use this one, if anyone is looking for a high quality tool "Made in Ireland" this is it. Not necessary with NiCopp on small jobs but thicker lines like tranny and fuel it really helps to make nice OE looking bends. http://www.amazon.com/Ridgid-Series-Instrument-Bender-Capacity/dp/B004FCO352
 

Smcatub

Thread starter
Messages
258
Location
Western NY
Ok, all went well. Well, not well, but I got the job done in the end. Once I took a close look I realized I wasn't going to make it to the master cylinder easily - it's too tight around there to get my hands in to the rear lined, which are on the bottom of the MC. So I got it up on the lift, traced the line back to good steel, and put a flare there. I think it took me six tries, between bad flares that leaked, breaking the flare tool die off in the line (!) and forgetting to put the nut on the line before I did the flare. The steel line was a real bear compared to the copper that I used for the replacement line. I am very glad I spent the money for the copper rather than cheaping out and getting steel PolyArmour line. It was $25 more per 50' coil and worth it for the saved frustration, not to mention the longevity of the line. Once I got it right I had to take the old line off the rear brake hose. It was rusted on so tight I needed to use a four foot jack handle to turn my ratchet. After two full turns with that I was able to get it off by hand. I was going to replace that brake hose, too, but the retainer clip was rusted so tight I couldn't get it off. I hosed it down good with PB Blaster, even tried hammering a screwdriver between it and the body clip it mates with. But it just wouldn't budge. The hose on there looked OK. The black had faded to dark, dark gray but there were no cracks or anything. So I decided to leave it, and I have a rear brake hose lying around when it comes time to replace one. During this whole process I accidentally let the master cylinder run dry. So I could have replaced the whole line in the end, because at that point I could have just removed the master cylinder for access to the bottom lines..... Oh well. I had to bleed the whole brake system now, not just the one line. That was OK since I wanted to anyway, just not right then at my friend's place. I was worried a bleeder might brake off and I didn't want to be stranded at his place (corrosion is a problem with this car, as you might hav guessed). But after some PB and careful coaxing, they all came loose. I flushed out about a pint of Coca-Cola colored old fluid and replaced it with water-clear Valvoline synthetic. I bought a quart of the Valvoline which was more than I needed. I'll know to get a pint next time. Oh, and in case anyone is wondering - the answer to my original question was - Rear lines are 3/16ths (4.75mm) and the flares are bubbles. Total cost of the project was about $66 including the copper/nickle brake line - a lot of which it left over.
 
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