I hate flare nuts!

[theholycow]

I'm angry at rusty flare nuts. There's like, too many of them and stuff.

Every fuel, brake, or transmission cooling system I touch has these all over the place:


The rust happens right near the nut and usually the line is clean a few inches away. The nut seizes to the threaded hole as well as seizing to the line.

I'm tired of hacking them up. I want to find a fucking magic way to unscrew these so that I can wirebrush them and reuse them without having to hack and splice.

Things that don't work:







I often google for new ideas. Yesterday I found this tip:

The vise-Grips prevent the flare wrench from flexing open, keeping it from rounding the nut.

Unfortunately, something's gotta give...and apparently it's not the nut.


I tried soldering it. I figured, that's how it's made at the factory and I'm equipped...should be good. FAIL. Solder wouldn't stick, no matter how clean, exposed, fluxed, and hot the metal is.

So, ghettoCow had to decide: JB Weld or Ultra Black RTV (high temp, maximum oil resistance). I went with JB Weld. Maybe I'll glob RTV on top of it tomorrow...belt and suspenders.

[stonehenge]

CSC

I am so glad I don't have to deal with rust. Fuck that.

[SarkOzy]

Holy shit. That thing must be rust-welded. Most likely it won't leak but


Why try to get it loose?

[theholycow]

That rust-welding is how most flare nuts are when I get to them.

I tried it because I wanted to do the complete fluid exchange (inaccurately labeled "flush") procedure.

After that debacle I decided to give another try to the drain plug on the transmission pan. It went from partially rounded to fully rounded. Fuck it...maybe I'll just leave the ATF in there until it fails.

[Ewok]

its because of dissimilar metals being joined together such as aluminum and steel it reacts causing corrosion and rust

[theholycow]

Pfft. You and your damned science.

Yeah, that's a good point. I've said it about other stuff before but I didn't even think of it in this case.

Fucking engineers are assholes. I have to buy a new truck, then make a schedule for nuts that need to be turned twice per year.

[BillyJeanKing]

I love corn nuts










i'm a doosh

[theholycow]

Repz for your nice nutz.

[BillyJeanKing]

[Ewok]

kourke freakin us wif his nutz

[theholycow]

MAH COOLER WON't LET GO OF MAH NUTZ! MY COOLER DON'T WANNA LET GO OF MAH NUTZ!

[stonehenge]

Cawrnnutz ftw

[SarkOzy]

Originally Posted by theholycow

That rust-welding is how most flare nuts are when I get to them.

I tried it because I wanted to do the complete fluid exchange (inaccurately labeled "flush") procedure.

After that debacle I decided to give another try to the drain plug on the transmission pan. It went from partially rounded to fully rounded. Fuck it...maybe I'll just leave the ATF in there until it fails.

It would have been much easier to disconnect the lines at the radiator where the fluid goes through the heat exchanger before going to the cooler. That's where I always do mine.

[theholycow]

If I did that, a bunch of fluid would remain in the cooler. Also, there's more room to work at the cooler. The one at the radiator isn't quite as brown and rusty but it's still very seized. There's a little better chance of success but the stakes are much higher if I break the radiator.

[SarkOzy]

That's why you tap into the return line from the cooler. I figured it would be less corroded at the radiator. The return line from the cooler should be connected at/near the radiator unless gm made it a one-piece hardline. I'd disconnect it there if possible, that way you don't fuck around with trying to get it loose from the radiator.

[theholycow]

One of us has it backwards.

I read the HowTo sticky on GMFS and decided that the upper one on the radiator is outbound to the transmission. I followed that and it goes to the cooler. The one I tried to wrench is outbound from the cooler to the transmission, I thought.

[SarkOzy]

On mine the upper line does go back to the transmission. I have it routed like so:

Bottom line on radiator - input from transmission
Top line on radiator - output to cooler

The line going from the output of the radiator is routed through the cooler and tied back into the transmission return, which runs the cooler in sequence with the radiator. I can snap a pic at lunch if you want.

The return line going to the transmission is connected to the cooler output via a 3/8" fitting at the radiator IIRC. I could unhook the cooler there and just hook it back up to the radiator if I wanted. The fitting is brass and the flare nut on the hardline is (insert grey metal here) so it doesn't tend to cause any galvanic corrosion.

That probably made no sense.

[theholycow]

Umm...how does "upper" differ from "top"?

"upper line does go back to the transmission" vs. "Top line on radiator - output to cooler"

[SarkOzy]

It doesnt:

[SarkOzy]

See what I mean? I have a connection at the outlet that I can unscrew.

[theholycow]

Mine is all hardline with flare nuts.

What I don't get is how you flush the cooler if you disconnect the radiator's output for your flush.

[SarkOzy]

Well I don't. I disconnect it at the connection that used to be the radiator output. I guess I could have said transmission return to be more clear.


That's what I thought. You have the stupid hardlines.

[shootermcgavin003]

at least there not truck nuts

[theholycow]

Necrothread!

The flare nuts that have given me the worst heartache are the ones at the fuel filter on my truck. They seize to the line even worse than they seize to the threads and I worry about replacing that line, it could get expensive. Well, apart from some of the weird OEM flares for high-pressure connections to rubber and nylon lines, I don't need to worry as much about it anymore.

This $7 Harbor Freight tool works perfectly:
http://www.harborfreight.com/tubing-bender-3755.html


That test was on a rotten rusty brittle 18 year old piece of line. No crush, no kink, no dimple, no fail. I proceeded to bend a new piece of line exactly the way I needed it.

The only thing it couldn't do was make a bend right near the flare nut, so flare it after bending or plan your bends further back. I ended up bending it by hand around an item with the right radius. I got a small dimple from that bend, but it'll flow plenty of fuel.


I have this OTC 4503 double flare kit ($33 if you don't use a coupon code):
http://shop.advanceautoparts.com/web...otc_17631616-p
Reviews are a little mixed, but there's demonstrations of it on Youtube and I expect to get good flares from it. I haven't used it yet.

I should have bought bulk 3/8" line and some flare nuts instead of the $17.50 18 inch section flared with a nut on one end/barbed on the other end with an included compression fitting that I'm not using...but this worked out well and I threw Advance a bone for all the 40% off purchases I've been making, at least $12 of that must have been profit.

CSB: When the guy showed me where it is, we saw that somebody had stolen the first one on the shelf. They didn't even open the ziploc bag, they just tore through it and took the pipe. That left a spare compression fitting, so the guy gave me that one...now I have two spare compression fittings that I bet I'll eventually need. That's worth a few bucks of that excess cost for that package.

Anyway I used it all for this SUR & R fuel line check valve.
http://shop.advanceautoparts.com/web...rts_22989642-p
http://fuelsender.com/fuel_line.html

I was going to have to cut this line to install it either way, so I wasn't too bummed when that damned flare nut was seized to the line again. It's a check valve made for retrofitting high pressure fuel systems whose in-tank fuel pump's check valve has failed and, at its ends, it is a compression fitting. Hundreds of dollars for a new fuel pump, or $30 for this? I'll settle for this.

Anybody have any tips on how tight to crank down a compression fitting? I never know and I think I always overdo it.

I wirebrushed the remaining old pipe and sprayed the entire new pipe assembly with Dupli-Color Rust Fix, which claims to catalyze rust into a stable paint-ready surface. I masked the appropriate places, of course. After a few minutes, the remaining traces of rust were indeed turning black, just as the marketing/instructions say. Tomorrow I'll paint it and then cover it in rubberized undercoating. After I install it, I'm going to seal in the flare nut so it can't seize to the line.

[lowerc]

don't you love all the rust? It never stops.

The compression fittings should be hand tightened and then spin it about 1 more full turn. It is inch pounds of torque we are talking here. They don't take much.

If you under tighten and pressurize your system and it leaks you can still snug it up a bit more. If you over tighten and it leaks you are fucked and need to replace it again.