Leaky brakeline fittings---Oh #!%*>

[brianangus]

Finally made it out to the garage tonite to bleed the brakes on the roadster pickup---even got a reluctant O.K. from Momma to help, as chief pedal pumper.--So, allright, figured I might as well get everything set up in the garage before I get her to tear herself away from "Jeopardy". --Filled the master cylinder with new fluid, bench bled the master cylinder as per instructions, put the lid back on, and started to pump pedal by hand to see if I can get some resistance.---Wait---whats that splashing I hear---look under car---Oh my Gawd---Looks like Niagara under there!!!!!
  Tomorrow I will go down to tool store and buy some box end brakeline wrenches, the kind with the slot in the box end to fit around the brakeline. I'm afraid to tighten things any more with my open end wrenches in case I screw up the fittings.--I used a double flare style flaring tool as per "standard operating procedure for brakeline fittings"---Hope I haven't forgotten how to do that properly. Ah well, three steps foreward and two steps back.

[enjenjo]

I have a steel adapter fitting that I use just to seat the double flare. It works better than a brass seat to make them seal. Particularly on home done flares.

[brianangus]

O.K., I think the leaks are healed up. Bought some good box end brakeline wrenches today, and was able to put some man size grunt on the leaking fittings. I bled the brakes, and got the missus to do the pedal pumping honours while I climbed around underneath fighting with bleed-screws. Momma makes a good wife, but a * grumpy mechanics helper. I go thru this every time I build a car---plumb the lines, fix the leaks, p___ off the wife by getting her to help pump the pedal.  Bleeding brakes is  one of the few things that you absolutely cannot do without a helper. There was so much mess on the floor that I sprinkled everything with floor-dry and quit for the night. Tomorrow night I will sweep up the floor dry, and watch for fresh drips on the concrete floor---not very scientific, but it does it for me. I will probably bleed the brakes a couple of more times between now and road time. The pedal is still spongy, but Momma's ugly quotient is directly related to how long I keep her out in the garage. I know that pumping the brakes supposedly aerates the fluid, but when you have the luxury of not immediately having to drive the car, any bubbles created will "settle out" in a week or so, and can be gotten rid of with the next bleed. I know that Summit has some neat check valve bleed screws, but when you only build one car every 10 or 12 years, its not a justifiable expense.

[enjenjo]

There is another way, gravity bleeding. It works. Open all the bleeder screws, and fill the master cylinder reservoir with fluid.  When is starts dripping out of a bleeder, close it, and watch the others. It sometimes takes several hours, but it does work.

[brianangus]

That only works for firewall mounted master cylinders. My master cylinder is under the floor. Fluid doesn't run uphill very good here.

[40]

I just did the brakes on my 36....I used the "Speed Bleeders" for the first time....they were about $5 each at the local auto parts.I simply cracked the bleeder 1/4 turn,attached a clear length of hose and ran it into a clean,clear bottle and after topping off the M/C,began pumping the pedal.I could watch the air/fluid thru the clear hose and just closed the bleeder after getting a nice bubble-free stream of fluid.I was able to get a nice firm pedal and didn't have to listen to a grumpy wife!I went back the next night and re-bled everything again and did get an additional bubble or two and the pedal became even firmer though I am assuming that when I hook up the vaccum line it will soften a bit.My wife is a very grouchy helper ....the speed bleeders were worth every penny!

[kb426]

One other option if you don't have a pressure bleeder. Mityvac. I bought the complete kit for about $50. Hand vacuum pump will allow you to do lots of things.

[C9]

I bleed brakes on my own with a compressed air supply.

A 1/2" thick flat aluminum adapter plate with gasket glued on has a couple of Schrader tank valves* installed to match each M/C reservoir.

The adapter plate gets installed on top of the M/C using the M/C cap flange for a seal against the gasket paper.  Some kind of clamping arrangement is required, I'll let you figure that part out, just make it easily removable cuz you have to remove the adapter plate to add fluid.

(Rubber gasket material works well, but the paper gasket material (Velumoid) I've been using has been hanging in there a number of years.

Run a regulated air source down to about 30# or so (or bring the compressor tank down to 30# with compressor power off.  It doesn't take much air quantity-wise).

Connect an air chuck to the adapter plate tank valve.  (Use the air chuck with the hold-on device so it will stay on the valve and supply constant air pressure.)

With the M/C bench bled and full of fluid as well as being pressurized with air, bleed the brakes as normal.
Refill the M/C after bleeding each wheel.

A fancier adapter plate could be made that has provisions for adding fluid while installed, but I've found using one clamp makes it easy to remove the adapter plate.

If you are using the FoMoCo Mustang style M/C under the floor it would be easy to weld or braze 1/8" pipe fittings into an extra M/C cap or add them to the cap that remains on the car and leave the tank valves in place.
Other brands of M/C's with a metal cap could be done the same.

This may sound like a lot of trouble, but it's a fairly quick way to do it.
If you built a pressure bleeder that held it's own fluid, you're still gonna have to make an M/C adapter plate.
Not to mention the brake fluid will pick up water if it's left in the pressure bleeder tank too long.


*Schrader tank valve - a fitting with 1/8" NPT (pipe threads) on one end, a hex for a wrench in the middle and the upper part looks exactly like the filler valve on your tires.
I buy them at real parts stores.

[Pope Downunder]

O.K., I think the leaks are healed up. Bought some good box end brakeline wrenches today, and was able to put some man size grunt on the leaking fittings. snip.

I'd like to know more about Frank's seating tool.

You need to be careful, as you can easily damage the inside of the joining fitting, hose, cylinder etc.  I was told by a mate who had done many of these jobs to make sure the seating surface is very good.  Then tighten it up firm, but not too tight, then back it off, have a look, then, if OK, do it up again tightly.

[flt-blk]

I One-Man-Bleed by using a length of tube with a coil in it off the bleeder.

I keep the tube above the caliper and the coil keeps fluid above the
bleeder when it sucks back a little.  All the bubbles go UP.  More goes out
than sucks back in, and you can do it by yourself.

Jay,
30# seems high for pressure bleeding, I used 10-15# with my hand
pump chemical sprayer attachment at the race track.  Lower the
pressure and you could use a less fancy gasket.