Brake Hard Line

Washing the truck today and noticed a brake leak. Get under and find the hard line fitting connecting to the caliper is leaking.

1) i topped up the fluid because the overflow was low.

B) ordered new hard lines for both front calipers along with rotors, pads, and braided brake lines. Was hoping to hold off until summer for the brakes but since im in there i might as well…

3) i have no choice but to drive it for work until im able to replace the lines (NEXT weekend) pray for me…

Never had to mess with hard line fittings before, are there any caveats? I tried to snug the fitting down with a 10mm but it wouldnt budge. Can anyone advise some tips to make sure I dont shear these fittings off in the caliper or where the other end connects to the rubber line? PB blaster and let it soak?

pics for clicks:

 

A good set of line wrenches.
I’ve never sheared one off, but I have rounded them off.
Harbor Freight is NOT good. Craftsman from Lowe’s is as low budget as I’d go.
Yes, I had the HF. I now have a set of MAC in standard of Craftsman in Metric.

 

I have the tool aspect covered

From what ive learned in the past theyre usually brass and softer than steel so chances of rounding or breaking are much higher

Was hoping to learn any “secret” tricks to pre loosening them, again the one on my drivers side is *possibly frozen. I put a craftsman 10mm on it, fit snugly but wouldnt turn, either way. I didnt try to hulk it for fear of breakage.

ill probably just hang in there until the new parts arrive provided i dont have to top off the master cylinder too often in the next week. When i do the job i’ll start by presoaking with penetrating oil. Im hesitant to apply heat but? Brakes are exposed to high temps but i also dont want to boil the fluid or anything…

Thoughts?

 

Heat it up. Be sure to change the fluid afterward of course which is easy because you’re replacing the line.

 

With an actual brake line fitting wrench not a regular open wrench?

Spray and soak daily till you get time to work on it. Then heat, and heat some more.

For some I use knipex wrenches, they clamp down harder as you apply pressure. Never used them on brake fittings but there hasn't been a nut those have slipped or rounded yet

 

Thanks!
Didnt know there was a specialized tool. Ill try to source one. And ill PB Blast the fittings for a few days before i start the work

 

I just changed mine and rebuilt new ones last summer. I tried for days to get mine loose without rounding them off, but they were completely frozen. But after 190K miles, just about everything has needed replacing except the engine

You’ll have to report back if you end up using the tool that point45 recommended. That might save all of us some headache in the future.

 

I use something like this to heat up small nuts/bolts and brake line fittings.

$23 Master Appliance MT-51 Professional Butane Torch Lighter, Hand Held Torch Lighter, Adjustable Flame Mini Blow Torch, Refillable with Butane Fuel for Soldering, Electrical Connectors, Kitchen, Cooking

https://www.amazon.com/Master-Appli...e-9d1a-0efc7c5c9374-spons&smid=A2QIS13XUMT4QN

 

https://www.homedepot.com/p/GEARWRENCH-10-mm-x-12-mm-Flex-Head-Flare-Nut-Wrench-81687/315529321

This is what you need, not specifically this brand but this tool. You might get lucky with an open end wrench but I wouldn't play Russian roulette with my brake lines, but that's just me. Your local auto parts store will carry a set if you want to go that route. I dont have the fancy flexible head, just about a 30 degree bend. Spray some brake cleaner around the area, use and shop towel or rag to clean up the mess and soak with some penetrant. Heat helps but it shouldn't be necessary. Having the right tool for the job is the bread winner. Open ended wrenches will round your nut.

-J

 

Thanks a bunch!

currently waiting on hard lines from the dealer before i start the work. Rotors, pads, and stainless brake lines will be delivered tomorrow.

Going through a bottle of brake fluid a day until repair day!

if i cant find a flare wrench quickly do you think it would be ok to notch a 10mm box wrench instead to undo the hard lines?

 

With how rusted they are I would not try a box wrench. I got a set of gearwrench line wrenches from Amazon and they fit well.

 

It needs to be replaced anyway...just cut the line and use a 6 point socket

 

I like your style!!

If i have to ill fold the end over and crimp it with a vise grip so i dont drain the master cylinder while im working

 

Is there any kind of sealant applied when installing the new hard line?

 

No, the threads do not seal anything. The tube nut (thing with the threads) once tightened, clamps the flared end of the line against a flare seat in the caliper. This is what creates the seal. Don't put anything on the threads.

 

No, the fitting has a conical seat and thats what seals it.

 

I’m not made of money, but I am about address this same issue on my 1998 4Runner and honestly. For the head ache and peace of mind, probably just gonna get a new hard line and a new calipers. Fuck um. Then can rebuild your old ones or return for the core. That truck is what, 17 years old? Don’t wanna mess with shitty brakes on your way home from work.

Edit: just read better, not exactly the same.. I have flare wrenches but still rounded off the bleeder and bled it using a vice grip. Nothing is leaking for me now, but I wanna just fix everything for peace of mind.

 

I always apply never seize to the line and the threads on the nut..

A smooth jaw vice grip is great for clamping rubber lines

All new brake fluid is a given being all the lines are being replaced.

 

Thanks for the feedback, i will replace the calipers if needed, thought of that for ease of replacement but its not in the budget unless its necessary to replace.

I’ll assume at least 2 large bottles of brake fluid to get me through the job

sourced a flare nut wrench set so i should have everything i need. Already have several torches i can use for heat application if needed.

 

Ok @wiggler, '98 to 2023 is 25 years, not 17.
Looka there! Your ole truck just became a vintage vehicle!