Hey folks,
This may be a dumb question but I have to ask. It seems I often don't have the right size wrench. For instance, I'm trying to remove the radiator cooler lines from my 71 Cutlass and the 1/2 inch is too big and the 7/16 is too small. I've tried different brands, some cheap, some expensive but it makes no difference. Do I really need a 15/32 for the tranny lines? Or is this something peculiar for flare nut wrenches? Do you folks have a lot of */32 wrenches?
Oh, and yes, I've tried my metric as well.
Thanks :-)

 

There are no dumb questions. I suspect the your transmission line tube nut has some rounded edges. It is hard to get an open end wrench into that area and a lot of times the wrench slips and rounds the corners of the nut. A I/2" tubing wrench may still give enough grip to break it loose. If that doesn't work I have used Vice Grips successfully in the past.

 

a good adjustable will get the job done. I don't like it any more than you do .. but it's a better choice than vice grips (at least until you've got it well rounded)

 

That's just the thing, I have more room than I had suspected, at least on the top line. I wire brushed the nut and used a little (read: a lot!) of PB blaster but the nut looks pristine, like it's never been touched. However, the wrench is really sloppy. No way I would even try to crank on it.
I'll try the adjustable and/or the grips. Thanks fellas.
-Mac

 

measure the nut with a caliper...interested to see what it is

 

No, because except in the small sizes (11/32 and below) they don't exist. As noted, the flare nuts rust and get rounded. This is not uncommon. If you don't have flare nut wrenches, get a set, however sometimes there's no alternative except for vice grips.

 

it should be half inch but you say the nut is not rounded and pristine...take a pic of that and .... i dont know.. thats odd

 

Don't take this wrong Mac .. what brand of wrenches?

 

No sweat Professur, I'm pretty thick skinned these days. I mean I beat out a gal for my job...and then she became my boss/chair So I can take just about anything, lol.
My wrenches are an assortment from years of doing "one job at a time" on the ol' daily drivers. Mostly Master Mechanic and Snap-On.
Huh, caliper reads 1/2". Maybe it's the wrenches but really, two different brands? Wait, make that three different brands.
Anyway, they're off. Vice Grips did the trick. Almost trashed the line though. The nut was bonded to the line more than the radiator!
Oh, and I found what might be a mouse nest behind the radiator

 

This is the only 32nd larger wrench I have seen, and I have never used it.
In the OP case, a tube wrench should have worked. They are a must. Some of my older open end wrenches have spread, even high quality ones.

 

I'll probably take flack for mentioning this, but what the hell. When I learned wrenching at my Dad's knee ... metric was just showing it's ugly face and Dad had a full set of imperial tools and wasn't about to drop money for more if it wasn't necessary ... (it wasn't for him ... he gave up working on his cars in '84). Whenever he ran into an odd sized nut, he'd pull out his old, battered feeler gauge and slip a shim into the gap to fill it up. It was nearly always enough to get the nut moving. I've got his tools and my own full metric sets .. but I still keep an old battered feeler gauge in the toolbox ... just in case.

 

Flack???? Heck that is a great idea. I never would have thought of that.

 

[QUOTE=m371961;593763]This is the only 32nd larger wrench I have seen, and I have never used it.

I remember back in the old days when I first started Wrenching some of the real old timers had some 32 nds wrenches. specifically 19/32 & 25/32 like you pictured. When I inquired what they fit (because I never found any use for them) the answer was Model A's and t's had some bolts that size. Now I am not sure that is correct because it is before my time
Glad the Op was able to get his line free. I would take Joe p's advise and buy a nice 1/2 x 9/16 line wrench to reinstall that thing.

 

There are sets of 3 line wrenches at sears. You'll need the smaller sizes for brake and fuel lines.

 

The feeler gauge trick is a great idea, and one I would not have thought of.
Thanks for the tip Oldcutlass, brakes are next.

 

A coin works well too, if there is some room round your stubborn nut or bolthead you can tap it in with a small hammer to get a real tight fit.
It only costs pennies, hahahaha......

Roger.

 

I've got some cheapo line wrenches and have used vise grips on the wrench instead of the nut itself a few times.

 

Definitely get line wrenches to save the flare nuts. Also, get to know which metric sizes are in between American sizes and which are almost equivalent. 12 mm is in between, as are 17, 18 mm, etc. Then, 11, 16, 19, 24 are virtually the same as 7/16, 5/8, 3/4, 15/16.

 

Using the feeler gage to take up clearance is ingenious.
Line [flare] wrenches are a necessity. Don't bother with less than Craftsman quality
Snap-on, Matco, Mac, or Craftsman. Accept no substitutes.
There is also this option, you only really need 1/2" and maybe 5/8 for fuel lines

http://www.mcmaster.com/#5515a13/=omtyfo

This was nicely in columns in its Excel home

Decimal Frac. mm Practical Meaning Notes
0.0625 1/16 1.59
0.1250 1/8 3.18 3mm is a bit smaller than 1/8
0.1563 5/32 3.97 4mm is interchangeable with 5/32" [0.001" diff]
0.1575 4.00 4mm is interchangeable with 5/32" [0.001" diff]
0.1875 3/16 4.76
0.1969 5.00 NO Fractional Equivalent to 5mm.
0.2165 5.50 5.5mm is pretty much interchangeable with 7/32" [0.002" diff]
0.2188 7/32 5.56 5.5mm is pretty much interchangeable with 7/32" [0.002" diff]
0.2362 6.00 6mm socket won't fit on 1/4" hex
0.2500 1/4 6.35 1/4" socket is 0.014" loose on 6mm hex, usually won't work
0.2756 7.00 7mm is pretty much interchangeable with 9/32" [0.005" diff] a GM favorite size
0.2813 9/32 7mm is pretty much interchangeable with 9/32" [0.005" diff]
0.3125 5/16 7.94 8mm is pretty much interchangeable with 5/16" [0.003" diff]
0.3150 8.00 8mm is pretty much interchangeable with 5/16" [0.003" diff]
0.3750 3/8 9.53 Need both 3/8 and 10mm in Universal Set.
0.3937 10.00 10mm 6-pt socket may work on 3/8 hex, not vice versa Common tool for M6 fasteners
0.4331 11.00 11mm is pretty much interchangeable with 7/16" [0.004" diff]
0.4375 7/16 11.11 11mm is pretty much interchangeable with 7/16" [0.004" diff]
0.5118 13.00 13mm is pretty much interchangeable with 1/2" Common tool for 5/16 or M8 fasteners
0.5000 1/2 12.70 13mm is pretty much interchangeable with 1/2"
0.5512 14.00 14mm and 9/16 interchange if sloppy enough
0.5625 9/16 14.29 14mm and 9/16 interchange if sloppy enough
0.5906 15.00 NO Fractional Equivalent to 15mm. a GM favorite size
0.6250 5/8 15.88 16mm is pretty much interchangeable with 5/8" [0.005" diff]
0.6299 16.00 16mm is pretty much interchangeable with 5/8" [0.005" diff]
0.6693 17.00 17mm is usually interchangeable with 11/16" [0.018" diff] Common tool for M10 fasteners
0.6875 11/16 17.46 17mm is usually interchangeable with 11/16" [0.018" diff]
0.7087 18.00 NO Fractional Equivalent to 18mm. a GM favorite size; often omitted from "sets"
0.7480 19.00 19mm is fully interchangeable with 3/4" [0.002" diff] Common Lug Nut Size [small]
0.7500 3/4 19.05 19mm is fully interchangeable with 3/4" [0.002" diff]
0.8125 13/16 20.64 21mm is pretty much interchangeable with 13/16" [0.014" diff] Common Lug Nut Size [large]
0.8268 21.00 21mm is pretty much interchangeable with 13/16" [0.014" diff]
0.8661 22.00 22mm is pretty much interchangeable with 7/8" [0.009" diff]
0.8750 7/8 22.23 22mm is pretty much interchangeable with 7/8" [0.009" diff]
0.9375 15/16 23.81 24mm is pretty much interchangeable with 15/16" [0.007" diff]
0.9449 24.00 24mm is pretty much interchangeable with 15/16" [0.007" diff]
0.9843 25.00
1.0000 1" 25.40 1" shaft won't go in a 25mm hole

 

Freaking genious.

Usually i just get frustrated and snap the cooler line and throw a 1/2'' socket on there.

This also meant i got to order a shiny new set of tubes from ILT.

 

Very complete conversion chart Octania, thanks for sharing. I picked up some craftsman flare wrenches. I hope they're better than their power tools.

 

I have a number of 32nd 12 point sockets my dad gave me from when he worked in the ship yards and a few 32nd combo box wrenches as well. Have used all of them at one time or another. Use them less now that I have a set of metric's

 

A plumber's wrench can come in handy sometime too. I find vise grips can distort the fitting to the point that it get stuck even more. Whatever it takes though.

 

Hey RROLDSX, I think I have one of those. Never thought to use it.

 

I've got a few x/32" wrenches, too, from my grandfather. Never get much chance to use them, though.

I always keep my metric wrenches handy (or my American wrenches when working on furrin cars) - if I encounter a fastener that's a bit too rusted, and the correct wrench fits too loosely, often a metric wrench will just tap on, and I can break it loose that way.

As for Vise-Grips, they can be indispensable for removing stubborn flare nuts.
The thing that will usually loosen flare nuts is a sharp tap, not a hard pull, and in order to transmit that sharp blow, you've got to have a firm connection to the nut. A loose wrench will "smush" a little bit and spread that blow over too much time.
A set of Vise-Grips, firmly and carefully applied so as to do minimal damage to the nut, but hold it tightly, will transmit a sharp hammer blow very effectively, and often save the nut by breaking it loose without the application of too much force.

- Eric