flare nut question
- Thread starter nyad
- Start date
Kevin54
MEMBER EMERITUS
An open end will do the job (sometimes), but a flare nut wrench or socket will grip the nut better than a standard wrench or socket as you have more surface area to make contact with, therefore less chance of rounding the flare nut off. Once you round it off, vice grips are the next alternative and I have seen many flare nuts with teeth marks in them.
On the machines I work on there are 192 coolant lines or more, and the fittings are very close together. A standard wrench cannot be used to remove the fittings because it will not fit. Most of the flare fittings are made of soft material, with a flare nut wrench or a line wrench it is usually wider to support the fitting better so you don't round it over.
Vinko
Well-known member
And correct me if I'm wrong: but I think you can also damage the line using a regular wrench. At least I've damaged them. But maybe it's because I was just being a jackass on the fuel lines.
TAMPAGT07
Well-known member
I like to use them when doing brake work for the brake fluid bleed fittings. Snap-on makes the best flare nut wrenches that I have used, and owned. I have used other that will expand and round the fittings.
HandyManny
Well-known member
Flare nut wrenches are also beveled on both sides to slip over the flarenut rather than engage it at a 90° angle. This makes for faster work than a standard open end wrench, in my experience. You won't damage the lines if you use an open ended wrench or adjustable wrench. It's like anything else, you just have to know what you're doing. As far as the best ones. Just buy a set from a reputable brand and they'll serve you well. It doesn't have to be Snap-On. There are many others that are just as good at a lot less money. S-K, Craftsman, Proto, come to mind.
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HandyManny
Well-known member
Not yet, but I've heard that the Snap-On trucks carry them, so they must be work their weight.
Joelfke
Well-known member
believe me. if you are working on rusted up brake/fuel lines, youre gonna want to use a line wrench. makes your world alot easier
TAMPAGT07
Well-known member
I had the craftsman ones years ago and got rid of them because they would open up enogh to round off the fittings. The Snap on ones were far superior and were very rigid. I cannot speak for the newer craftsman ones, since I have never used them.
-B-
Well-known member
+1
I have seen the results of open end wrenches it is not pretty when the fittings let go.
Scooterfish
Well-known member
Keep in mind line fitting are generally soft so your looking for exact fit with max. wrench contact on fitting.
JayL
Well-known member
I do and I am happy with my Metric Set.
http://www.amazon.com/dp/B000NI93SE/?tag=atomicindus08-20
The price increased now to $54 but IIRC I bought mine for around $38.
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Art From De Leon
Well-known member
Even with a flare wrench I still don't trust that freakin line. Had one too many twist on me...
I ran into that quite a bit when working on tractors. If you take a punch and set it on the exposed side of the hex, and hammer on it, it usually will break the corrosion that is between the line and the nut.
Merkava_4
Banned
Because alot of the flare nut fittings are hollow and therefor not as strong as a solid nut. And so with a flare nut wrench, you're spreading the force evenly across all 6 sides of the fitting instead of just 2 sides with a regular open end wrench.
Autoguy
Well-known member
Yo must use them with soft metals like copper and aluminum fittings.
If a an open end works great, but I run into hoses that seem to weld themselves together. The $1000 radiator my car uses has plastic end tanks with coolers for the oil and transmission. I worked on getting the radiator end of the transmission hose loose for a couple days, spraying with kroil, etc., ended up cutting the hose to get it out of the car and with two box end long style wrenches slid down the hose could not budge the fitting.
Sent it to the radiator shop to flush and pressure check and they couldn't get the hose loose. Couple more days after I got it back soaked it with penetrating oil again and it turned into kind of a shop challenge with each of guys trying it sword in the stone style. Eventually I think we used a prybar with two box ends and some rope, but it did come apart.
Open end would have wrecked the fitting before we got close to the amount of force needed. I'm not sure a flare wrench would have worked either, which is why we used box ends.
Unless you are changing the line anyway, had a couple where I've cut the line & used a 6 pt socket.
fomocoforrester
Well-known member
- Joined
- Jun 13, 2008
- Messages
- 3,061
The other reason a flare nut wrench is wider is to provide extra stifness to prevent the jaws spreading.
Sometimes people try to make a flare wrench by cutting an opening in a box end wrench. This is rarely successful as the resulting jaws are too flexible.