Another Brake question:

[Lester]

For those who helped me with my brake questions a few months ago, I am back at it. I re-threaded my Wilwood Master Cylinder .700 (I got excited, and cross-threaded it). I put it on today, it fit like a glove. Here's where I need some help: I know the line is tight, it doesn't leak. I flared the line with no problems. I put fluid in it, pressed the pedal, and...nothing. The fluid did not go anywhere. The front left bleed screw was open. The car was not running. I have no idea if my servo is working. What am I doing wrong? Does the car need to be running to bleed the brakes???
Endless thanks, Lester

 

[mikephillips]

Were the brakes drained or the lines still full?? If they were drained then it requires a number of pumps to get fluid to the bleeder screws. If they were left full I would guess that something is blocking the line. I once had a small chip fall into the t fittiing as I was assembling new lines and it was just big enough to block the hole in the fitting. This caused me to spend several hours trying to figure out why the system wouldn't fill as I pumped the pedal. I changed masters and checked everything I could think of before discovering it. So, since you needed to rethread the port on the master the first thing I would do is ensure no small bits of metal dropped inside and are blocking the holes or stopping the internals from fully working.

 

[Bill Blue]

Lester, can't tell from your post, so I have to ask: Do you know the general proceedure for bleeding brakes? If not, that is probably your problem.

Bill

 

[Jeff Scoville]

Also bench bleeding the Master prior to install makes things go quicker.

 

[Lester]

No, Bill, I've only bled brakes once prior. You're probably right on that one.
I was hoping you guys could fill in a few blanks for me. I understand the general process. I just can't figure out why the fluid is not being pumped into the line. Any pointers for bleeding alpines would be great! I'll check for blockage; that is very possible.
Lester

 

[Wombat]

Lester

The engine does not need to be running. When I bleed brakes, I start at the wheel with the longest pipe run (right rear in your case??) and finish at the wheel with the shortest pipe run. You will need to pump the pedal many times and refill the master cylinder periodically during the process.

One possibility is that the fluid is disappearing into the vacuum chamber of the booster. These boosters (and their Lockheed equivalent) have been known to do that.

Good Luck

 

[Bill Blue]

Lester, don't know where you are on your bleeding knowledge base.

There are no valves in the system to help you pump, so you need an assistant. I like to start on the farthest wheel, open the bleeder valve, stick my finger over the bleeder valve opening and have the assistant pump the pedal. This works quite nicely, your finger acts as a valve, letting air out and sucking fluid into the system. When you get a steady stream of fluid, close the valve and go to second farthest wheel and repeat. When there are no more wheels, you should have a nice hard pedal.

If you've done that and still have zero pedal, you got PROBLEMS.

Bill

 

[Nickodell]

Best way is to make it a 2-man job. Push a short length of clear plastic tube on the farthest, i.e. rear, bleeder (the Alpines, at least my SV, only have one rear bleeder) and put the other end into a clean glass jar with an inch of fluid in. This is to prevent air re-entering the syetem from the bleeder when you lift your foot. Have an assistant stand by with a can of fresh fluid, and station him where he can see the jar and also be close to the fluid reservoir. Cover the fender with a plastic garbage bag to prevent fluid drips from lifting the paint.

Pump the pedal hard (to drive out air bubbles). Your helper should see bubbles coming into the fluid in the jar, along with (probably) dirty fluid already in the system, unless you replaced all the brake lines too. Make sure he keeps the fluid reservoir filled while you pump, until no air and only clean fluid comes out.

Repeat the process on the front left and right bleeders. Don't forget to re-tighten the bleeder screws - I have, and it gives you the interesting experience of your foot going to the floor.

Brake fluid decomposes and picks up moisture in time, and also corrodes the interior of the brake lines on older cars (newer ones use nickel alloys that don't corrode). You should change the fluid every two or three years to help prolong the life of the system.

 

[Lester]

Lester

The engine does not need to be running. When I bleed brakes, I start at the wheel with the longest pipe run (right rear in your case??) and finish at the wheel with the shortest pipe run. You will need to pump the pedal many times and refill the master cylinder periodically during the process.

One possibility is that the fluid is disappearing into the vacuum chamber of the booster. These boosters (and their Lockheed equivalent) have been known to do that.

Good Luck

Thanks guys! The fluid is not going anywhere. It's not a matter of where, but why not. It's possible that it's just pulling air in the system, and I need to seal the valve with my finger. I'll try that and post on Sunday. I'm in
Dallas right now. Again, thanks. -Lester

 

[oldflotsam]

Lester, if you're in Dallas, watch out for Steve Kirk driving his red SII fron the passenger seat. You won't see me, the brakes are locked up on my yellow S3.

Wayne

 

[Chuck Ingram]

I just have to add to this thread.
I think I would undo the brake lines from the cylinders and the MC as well as the T joint.I would blow air backwards with at least 80 PSI. through all the lines.This is to insure there is no blockage.While the lines are not connected check to see if fliud will come from the MC either by gravity or pedal pressure.Now make sure the T joint is clear and there are no bits of rubber seal obstructing the opening to the lines.As to the fliud going into the server this will happen most of the time if it is faulty when the engine is running. You can by pass this to verify.You can get by bench testing the MC by leaving the front bleeder open and let gravity bleed the front.When you see fliud you can then go to a normal bleeding procedure.Be sure to keep the fluid level up or you will have to start bleeding all over.
This will or should leave you with a nice firm pedal

 

[Lester]

Well, the fluid is now pumping through the system. It can't figure out why it wasn't earlier. I found that my booster was sucking fluid, so I just bypassed it. Is there anything special that she be done here? All I did was take the line going into the booster and put it straight into the splitter. I still need to bleed it a bit more, but with all lines closed, and the fluid topped off, it's still soft. Also, the brakes aren't working. Any thoughts? I am not seeing any leaks. Still, I took it out on the road a bit. It was great fun! The engine put out ok, after sitting for almost 4 years. I had some trouble getting it started again, when it died in the driveway afterwards. There was a little leakeage around the valve cover, and the oil pressure dropped a bit after the drive. An eventful day, all in all. Working on the this car is a lot like watching the TV show, Lost. It certainly left me with more questions that it answered. Only time will tell...thanks everyone for all of your help.
-Lester

 

[Nickodell]

Spongy brakes almost always means air in the system. Needs to be purged; if you use the tube into the jar method you'll see if air is coming out.

 

[Bill Blue]

Lester, is the pedal going to the floor with only minor resistance? If so, you probably need to bleed some more. When bleeding, the person pumping should depress the pedal quickly to flush out air pockets. Another problem could be very poorly adjusted rear brakes, requiring more than a single application to expand the shoes out to the brake drum. The shoes should drag lightly when the wheel is turned.

Your bypass of the booster sounds fine.

Bill
(edit) and if you use the "finger over the bleeder screw opening", you'll feel the air escaping.

 

[Lester]

that's good to know that it's probably just air in the lines. I knew there was still air in there, but did not know the brakes wouldn't work. I am a novice at this, as you well know by now. Thanks for your patience. I'll let you know my results.
Lester