Build Thread 1978 Fairmont. I bet somebody back home’s thinkin’…I wonder why he don’t write..?

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Hmmm..wondering why the front brakes would never stop sucking in air? Do the two separate ports of the master cylinder share an opening? In other words, would a leaking secondary port allow air to get into the primary side if sucking fluid through the system like I was doing last night?
 
I was thinking that was probably the case till I pushed the brake pedal and it was spongy. I removed the leaking line, and put a plug in its place, and the pedal instantly got better.
Are you sure the bulbbles werent because the bleeder was too loose and pulling air through the threads? I had a hard time bleeding mine and discovered that.
 
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Hmmm..wondering why the front brakes would never stop sucking in air? Do the two separate ports of the master cylinder share an opening? In other words, would a leaking secondary port allow air to get into the primary side if sucking fluid through the system like I was doing last night?

no. They draw separately from the reservior, which is baffled to separate fluid sources. Part of the safety aspect of the MC if a line fails
 
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Mike, I know it seems like you have been back and forth on the car, but you have basically redesigned the whole car. From an outside perspective, you're finishing the last couple percent of "done." Likely really hard to see from your perspective, but I recommend you step back and give it a moment before deciding to get rid of her. Just my 2 cents.
 
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I think they’re bled. It’s one of those things where I never know if it’s done. I have what feels like a good firm pedal, but I’m always wondering if it could be better. One things for sure, I’ve definitely managed to completely flush out the old fluid out of the system. The front bleeder screws are letting air get past them when trying to do a vacuum assisted brake bleed. I thought putting an oring over the threads of the screw would help seal it, but every time I shut the valve, the oring raised up a thread, and when I opened it again, the oring was above the caliper..
I guess the main thing was that clean brake fluid was pulling out of the caliper..the fact that air was finding its way down the threads may or may not have compromised the process. If i can drag kate down there on Sunday, I’ll do a regular bleed just to check. ( All while listening to how this is making her leg tired).
image.jpg

( this time i wasn’t forced to try and make an old line fit like before,...i started with a new one and bent it to fit)

I ordered a new AC drier..that’ll be here on Sat. If it gets here then, I’ll swap it out and put the thing back on the ground again. Depending on the weather..take it out for a test drive and see if this differential behaves any better with a slightly tweaked axle end.

More frustration to come i’m sure.
 
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I think they’re bled. It’s one of those things where I never know if it’s done. I have what feels like a good firm pedal, but I’m always wondering if it could be better. One things for sure, I’ve definitely managed to completely flush out the old fluid out of the system. The front bleeder screws are letting air get past them when trying to do a vacuum assisted brake bleed. I thought putting an oring over the threads of the screw would help seal it, but every time I shut the valve, the oring raised up a thread, and when I opened it again, the oring was above the caliper..
I guess the main thing was that clean brake fluid was pulling out of the caliper..the fact that air was finding its way down the threads may or may not have compromised the process. If i can drag kate down there on Sunday, I’ll do a regular bleed just to check. ( All while listening to how this is making her leg tired).
image.jpg

( this time i wasn’t forced to try and make an old line fit like before,...i started with a new one and bent it to fit)

I ordered a new AC drier..that’ll be here on Sat. If it gets here then, I’ll swap it out and put the thing back on the ground again. Depending on the weather..take it out for a test drive and see if this differential behaves any better with a slightly tweaked axle end.

More frustration to come i’m sure.
If you have any doubts, see if you can use your BMW dealership's brake flush machine, if they have BG's machine like we have here, it'll get any remaining air out.
 
If you have any doubts, see if you can use your BMW dealership's brake flush machine, if they have BG's machine like we have here, it'll get any remaining air out.
maybe when I take it back there I can get me a triple header:

It needs a new front end alignment because I changed it when I solved the moving lower strut mount issue.
It needs the benefit of a Ryanaire AC recharge station...
And..( although I don’t know how they’ll get around the leaking bleeder valves)..The BMW brake fluid transfusion system seems to work pretty damn good.
 
I think they’re bled. It’s one of those things where I never know if it’s done. I have what feels like a good firm pedal, but I’m always wondering if it could be better. One things for sure, I’ve definitely managed to completely flush out the old fluid out of the system. The front bleeder screws are letting air get past them when trying to do a vacuum assisted brake bleed. I thought putting an oring over the threads of the screw would help seal it, but every time I shut the valve, the oring raised up a thread, and when I opened it again, the oring was above the caliper..
I guess the main thing was that clean brake fluid was pulling out of the caliper..the fact that air was finding its way down the threads may or may not have compromised the process. If i can drag kate down there on Sunday, I’ll do a regular bleed just to check. ( All while listening to how this is making her leg tired).
image.jpg

( this time i wasn’t forced to try and make an old line fit like before,...i started with a new one and bent it to fit)

I ordered a new AC drier..that’ll be here on Sat. If it gets here then, I’ll swap it out and put the thing back on the ground again. Depending on the weather..take it out for a test drive and see if this differential behaves any better with a slightly tweaked axle end.

More frustration to come i’m sure.
I'm surprised that you don't have one of these...
If you do and said so, I missed that fact when reading your post.

Garden Sprayer Pressure Bake Bleeder

1 each pump type garden sprayer, 1 - 1 ½ gallon capacity (size doesn’t matter much, it just has to be cheap and small enough to be easy to work with)
6-10 feet 3/8” clear plastic tubing
1 each ¼” brass pipe tee
1 each ¼” pipe to 3/8: hose adapter
1 each pressure gauge 0-30 PSI or so – all you’ll ever need is 5- 10 PSI, so the gauge range doesn’t have to be high.
1 each large rubber stopper – this is the hard part to find. It may take some searching to find one that is a snug push fit to the inside of the filler port on the master cylinder. You can use silicone rubber to seal a brass fitting to an old master cylinder cap, but they tend to leak too much.

Home Depot or Lowes has some ¼” brass pipe stock that is continuously threaded in the electric lamp repair department, along with the brass nuts that go with it. This is better than a pipe nipple, since the nuts can be used to secure the pipe in the cap or stopper.
OR if you can’t find the threaded pipe stock,
1 each ¼” nipple, 1 ½”- 2” long

The rubber stopper needs a hole drilled in it for the ¼” pipe nipple or threaded pipe stock. After you drill the hole, use some silicone gasket sealer to seal the pipe nipple as you push it into the rubber stopper. If you used the threaded pipe stock, use the nuts to secure the stock into the stopper.

If you can’t find a suitable rubber stopper, an old master cylinder cap can be used. Drill a ½” hole in the center for the pipe fitting. Cut the brass pipe stock to about 1”- 1 ½” long, the exact length isn’t too important. Push it through the hole in the master cylinder cap and thread one nut on top of the pipe stock where it sticks though the cap. Put another nut on the other side of the cap to lock the pipe stock in place. Apply some silicone rubber gasket sealer to both sides and when it is dry, screw the ¼” pipe that sticks out of the top of the cap into the tee.

Remove the sprayer hose and wand from the garden sprayer. You may find it easier just to cut the sprayer hose off short and connect it to the 3/8” plastic tubing. The idea is that the 3/8” tubing connects to the pickup tube inside the sprayer in a reliable, leak proof fashion. Another alternative is to remove the spray nozzle from the end of the spray wand and connect the 3/8” tubing to the wand. This leaves the hand valve in place and may be useful to start/stop the flow of brake fluid.

The 3/8” plastic tubing connects to the pipe tee using a push on hose barb type adapter. The pipe tee has one port for the gauge, one for the 3/8” hose and the other to connect to the rubber stopper or master cylinder cap that you modified.

Fill the pump sprayer with a quart of brake fluid. Set the garden sprayer on the ground and screw the pump handle down tight, and pump until brake fluid fills the plastic tubing. Then put the modified stopper or master cylinder cap on the master cylinder and pump slowly to make sure that nothing leaks or pops loose. No leaks, continue pumping until you get 5-10 PSI.

WARNING: Do not let the fluid level in the garden sprayer get low, or let the garden sprayer tip over so that it pumps air into the brake master cylinder. This is the only problem with this inexpensive brake bleeder, but it isn't hard to avoid.

Start with the brake assembly furthest away from the master cylinder. On 5.0 Mustangs, it's the passenger side rear brake. Follow up with the driver side rear brake, passenger side front brake and the driver side front brake. Put a 6”-12” length of clear plastic tubing on the bleeder ports. Then open the bleeder ports on the wheel cylinders one at a time and bleed until the bubbles are gone. I use a 2 liter soda bottle with a coat hanger to catch the fluid . DO NOT REUSE THE OLD BRAKE FLUID. Repeat the process until you have finished all 4 wheels. You will have to pump the sprayer several times to maintain the 5-10 PSI needed to do the job. When finished bleeding, loosen the pump handle to relieve the pressure, remove the stopper/modified master cylinder cap and test the pedal.
 
I'm surprised that you don't have one of these...
If you do and said so, I missed that fact when reading your post.

Garden Sprayer Pressure Bake Bleeder

1 each pump type garden sprayer, 1 - 1 ½ gallon capacity (size doesn’t matter much, it just has to be cheap and small enough to be easy to work with)
6-10 feet 3/8” clear plastic tubing
1 each ¼” brass pipe tee
1 each ¼” pipe to 3/8: hose adapter
1 each pressure gauge 0-30 PSI or so – all you’ll ever need is 5- 10 PSI, so the gauge range doesn’t have to be high.
1 each large rubber stopper – this is the hard part to find. It may take some searching to find one that is a snug push fit to the inside of the filler port on the master cylinder. You can use silicone rubber to seal a brass fitting to an old master cylinder cap, but they tend to leak too much.

Home Depot or Lowes has some ¼” brass pipe stock that is continuously threaded in the electric lamp repair department, along with the brass nuts that go with it. This is better than a pipe nipple, since the nuts can be used to secure the pipe in the cap or stopper.
OR if you can’t find the threaded pipe stock,
1 each ¼” nipple, 1 ½”- 2” long

The rubber stopper needs a hole drilled in it for the ¼” pipe nipple or threaded pipe stock. After you drill the hole, use some silicone gasket sealer to seal the pipe nipple as you push it into the rubber stopper. If you used the threaded pipe stock, use the nuts to secure the stock into the stopper.

If you can’t find a suitable rubber stopper, an old master cylinder cap can be used. Drill a ½” hole in the center for the pipe fitting. Cut the brass pipe stock to about 1”- 1 ½” long, the exact length isn’t too important. Push it through the hole in the master cylinder cap and thread one nut on top of the pipe stock where it sticks though the cap. Put another nut on the other side of the cap to lock the pipe stock in place. Apply some silicone rubber gasket sealer to both sides and when it is dry, screw the ¼” pipe that sticks out of the top of the cap into the tee.

Remove the sprayer hose and wand from the garden sprayer. You may find it easier just to cut the sprayer hose off short and connect it to the 3/8” plastic tubing. The idea is that the 3/8” tubing connects to the pickup tube inside the sprayer in a reliable, leak proof fashion. Another alternative is to remove the spray nozzle from the end of the spray wand and connect the 3/8” tubing to the wand. This leaves the hand valve in place and may be useful to start/stop the flow of brake fluid.

The 3/8” plastic tubing connects to the pipe tee using a push on hose barb type adapter. The pipe tee has one port for the gauge, one for the 3/8” hose and the other to connect to the rubber stopper or master cylinder cap that you modified.

Fill the pump sprayer with a quart of brake fluid. Set the garden sprayer on the ground and screw the pump handle down tight, and pump until brake fluid fills the plastic tubing. Then put the modified stopper or master cylinder cap on the master cylinder and pump slowly to make sure that nothing leaks or pops loose. No leaks, continue pumping until you get 5-10 PSI.

WARNING: Do not let the fluid level in the garden sprayer get low, or let the garden sprayer tip over so that it pumps air into the brake master cylinder. This is the only problem with this inexpensive brake bleeder, but it isn't hard to avoid.

Start with the brake assembly furthest away from the master cylinder. On 5.0 Mustangs, it's the passenger side rear brake. Follow up with the driver side rear brake, passenger side front brake and the driver side front brake. Put a 6”-12” length of clear plastic tubing on the bleeder ports. Then open the bleeder ports on the wheel cylinders one at a time and bleed until the bubbles are gone. I use a 2 liter soda bottle with a coat hanger to catch the fluid . DO NOT REUSE THE OLD BRAKE FLUID. Repeat the process until you have finished all 4 wheels. You will have to pump the sprayer several times to maintain the 5-10 PSI needed to do the job. When finished bleeding, loosen the pump handle to relieve the pressure, remove the stopper/modified master cylinder cap and test the pedal.
Why couldn’t I just get another master cylinder cap, and put a regulated airline from the compressor in the cap? fill the MC to the brim, screw on the cap, set the pressure to 5 psi, and pressurize the MC, stopping, and refilling the MC as necessary as I move to each of the 4 wheels?
 
Why couldn’t I just get another master cylinder cap, and put a regulated airline from the compressor in the cap? fill the MC to the brim, screw on the cap, set the pressure to 5 psi, and pressurize the MC, stopping, and refilling the MC as necessary as I move to each of the 4 wheels?
Doing it your way, it's too easy to miss the needed refill of the master cylinder. Then you have the whole system full of air. Use a quart of brake fluid and your chances of getting a bunch or air in the system are very small. That's because you need to pump the sprayer up fairly often if you stick to using the 5-10 PSI recommended pressure

Done carefully, you can flush and bleed all 4 wheels of the brake system in one session.
 
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Hell, who am I to argue?
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Im firmly convinced that there must've been something wrong with that junky locker differential..Car went from snapping and popping ( even while going straight) to almost a joy to drive..
The brakes still aren't right, but they are better than the manual version..the pedal is way too soft though.
The check valve that goes into the booster is a one way..so I didnt add back the inline check valve I used to have on the car when it used to have power brakes. Im wondering if boost is blowing by that ck valve ..
But, the helical diff is dead quiet, with no weird quirks. The Torque arm didn't cause anything weird under full power pulls either..I took it out for a short drive earlier, then while sitting here thought..
That was too short..lets do that again.
 
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Hell, who am I to argue?
20210131_153442.jpg

20210131_153738.jpg

20210131_153751.jpg

20210131_153853.jpg
20210131_153818.jpg

Im firmly convinced that there must've been something wrong with that junky locker differential..Car went from snapping and popping ( even while going straight) to almost a joy to drive..
The brakes still aren't right, but they are better than the manual version..the pedal is way too soft though.
The check valve that goes into the booster is a one way..so I didnt add back the inline check valve I used to have on the car when it used to have power brakes. Im wondering if boost is blowing by that ck valve ..
But, the helical diff is dead quiet, with no weird quirks. The Torque arm didn't cause anything weird under full power pulls either..I took it out for a short drive earlier, then while sitting here thought..
That was too short..lets do that again.
I am sincerely glad that you can finally enjoy the fruits of your labor. A lot of work has turned around and you can enjoy having some fun now.
 
I sincerely hope he puts many trouble free miles on the monster, I also hope he clips off a good timeslip, he knows we want to see the run.
I personally like a little sideways tire smoke'n for about a150ft action.
Maybe we get that stuff, maybe not.