20 year in the garage... Car is ready but brake fluid is not going to the calipers

DanielForest

DanielForest

True Classic
OK. Long story short. Stored to repair the engine. Took longer than expected. I changed the hoses from the reservoir to the master cylinder. Changed the master cylinder. And at each corners, I changed the flex hoses, the calipers, the rotors and the pads.

A few days ago, I filled the reservoir with Dot 4 synthetic brake fluid, then removed all the bleed screws. No fluid at the calipers. I pumped the pedal a few hundreds time. Nothing. I used the MightyVac vacuum, a few hundreds pull. Nothing. I have speedbleeders, so no need to screw/unscrew each time. When I say nothing, I mean the brake fluid level at the reservoir didn't move.

The nose of the car is higher than the calipers to help gravity feed.

I opened a buble flare hard line at the master. Fluid started to leak as soon as I untightened it, so I rebolted everything because I knew the brake fluid was reaching and exiting the master.

The master cylinder is new but it's in the car for a few years, the time it took me to do other parts of the car (I'm slow and I didn't had much time). So that may be the master... but still, the mightyvac should pull the fluid.

I wasn't sure what was the best master position to help fluid circulate, so I tried with the pedal relaxed and with the pedal to the floor, jammed with a wood plank.

So what's next?

Maybe it's all normal and I'm not just patient enough.
 
Last edited:
DanielForest said:
OK. Long story short. Stored to repair the engine. Took longer than expected. I changed the hoses from the reservoir to the master cylinder. Changed the master cylinder. And at each corners, I changed the flex hoses, the calipers, the rotors and the pads.

A few days ago, I filled the reservoir with Dot 4 synthetic brake fluid, then removed all the bleed screws. No fluid at the calipers. I pumped the pedal a few hundreds time. Nothing. I used the MightyVac vacuum, a few hundreds pull. Nothing. I have speedbleeders, so no need to screw/unscrew each time. When I say nothing, I mean the brake fluid level at the reservoir didn't move.
Click to expand...
Have a close look (or feel, not easy to see anything there) where the hoses go through the firewall and into the frunk. It is very easy to kink the hoses here, particularly if you didn't have a helper pull on the hoses as you lifted the pedal box into place.
 
All good tips. I changed the hoses twice. At first, I was using clear Tygoon and they were kinked at that exact place (entrance to the firewall).

I have fluid at the master, but maybe not enough... Possible I have a hose kinked under the dash when I bolted back the pedal assembly.
 
Hoses are looking good... as I can see without removing the pedal box, but there is a leak at the master... A drop slowly forming under the master, then falling on the brake switch before hitting the brake pedal. That's didn't help solving my bleeding problem but it lead to removal of the master or the pedal box. I'm not sure which one is more complicated. I had so much trouble putting back the pedal box. Then a second time to replace the clear Tygoon hoses. Then now, a third time. I would prefer to remove the engine and transmission. Or even changing the heater valve 10 times... I'm even considering fitting a Tilton unit in the frunk...

Keep throwing suggestions. In the meantime I will try to convince myself to go lay on my back under the dash for another time.
 
I just did this on a X that had been sitting for years also. On front right hard line I had old brake fluid solidified in a curve part of the line and had to run a small diameter wire through it to loosen it up.
Also one of my calipers had a clog at the bottom of the bleeder valve seat .
 
michaelmn said:
I just did this on a X that had been sitting for years also. On front right hard line I had old brake fluid solidified in a curve part of the line and had to run a small diameter wire through it to loosen it up.
Also one of my calipers had a clog at the bottom of the bleeder valve seat .
Click to expand...

Thanks. I don't believe this is my case. The calipers were removed years ago and at that time the fluid was freely dripping in some jars. Also, I'm having 4 brand new calipers now. I currenctly can't get any fluid at all calipers. I doubt old brake fluid would have solidified at all corners.

Bleeding brakes is one of the most frustrating job on a Fiat x19. Changing the master is THE worst job. I was even considering selling the car if I had to do it again. Then I have to do it again. It's bad to do it once. Why 3 times to get things right...

Maybe I will try to remove just the brake master cylinder this time. If it didn't work, then I will drop the pedal box.🥵
 
As the piston moves inward in the brake master cylinder, the fluid supply ports close, and you start building pressure (assuming there is fluid...). Are you sure you are not applying any force to the piston in the master cylinder? Perhaps remove the brake light switch (so the pedal retracts fully) and try gravity bleeding again?
 
I will try to fix this, but next time it's going to be:
tiltonracing.com

600-Series Firewall-Mount Aluminum Pedal Assembly

The low weight 600-Series firewall-mount aluminum pedal assembly provides excellent performance at competitive prices.
tiltonracing.com tiltonracing.com

Thanks Bjorn, I will release the brake switch, but since there is already a small leak, I must take care of that first. Maybe I will find a clue while doing it...
 
Maybe the leak is coming from the hardline you loosened momentarily? It does seem odd that you can get fluid to that point but not to the caliper, can you blow some air thru the hardlines to check they aren't blocked? Maybe the speed bleeder valves are blocked? If you have to pull the master out again bench test it before pulling it apart to try and see what's happening. And bench test the replacement. Good luck.
 
GregS said:
Maybe the leak is coming from the hardline you loosened momentarily? It does seem odd that you can get fluid to that point but not to the caliper, can you blow some air thru the hardlines to check they aren't blocked? Maybe the speed bleeder valves are blocked? If you have to pull the master out again bench test it before pulling it apart to try and see what's happening. And bench test the replacement. Good luck.
Click to expand...
The leak is coming from the master. I hope it's just a fitting or a hose. I don't want to replace the master again. I will seriously consider a Tilton pedal with the reservoir and the master in the frunk.

The speedbleeders are brand new and there is no fluid reaching the calipers even when I removed the bleed screw completely. I will try blowing air to check if the problem is with the hardlines.

Suggestions on how to bench test the master?

I'm presently having fun trying to remove the long bolts... When the pedal box is removed, that's easy, but maybe I will follow the tip of replacing the bolts with studs/nuts on each side.
 
Open up a hard line at one of the calipers. Does that flow a lot of fluid, and drop the level in the reservoir?
 

Ready to give up- front brakes won't bleed, pedal goes to floor

Hi, sorry I haven't been on the forums in a long time. I am trying to prepare my 1980 X for sale, and I started having a brake problem. Based on research, I figured it was the master cylinder giving up. I tried replacing it, but couldn't get the front brakes to bleed either with forced air into...
xwebforums.com
This post may give a few more ideas.
If you remove the whole pedal assembly you can bench test with a make shift fluid reservoir and pushing the pedal just to see if fluid squirts out and is refilled by the reservoir, or you can just push the piston end with a screw driver.
More info : https://xwebforums.com/forum/index.php?threads/brakes.29367/post-245735
 
Last edited:
DanielForest said:
The leak is coming from the master. I hope it's just a fitting or a hose. I don't want to replace the master again. I will seriously consider a Tilton pedal with the reservoir and the master in the frunk.

The speedbleeders are brand new and there is no fluid reaching the calipers even when I removed the bleed screw completely. I will try blowing air to check if the problem is with the hardlines.

Suggestions on how to bench test the master?

I'm presently having fun trying to remove the long bolts... When the pedal box is removed, that's easy, but maybe I will follow the tip of replacing the bolts with studs/nuts on each side.
Click to expand...

In these situations it is often a good idea to try bleeding directly from the master first. Crack open one of the hardlines on the master and push the pedal a couple of times (tightening as you release the pedal). Obviously, cover the floor with a few towels first. This way you will have a good supply of fluid going all the way through the master cylinder first without the additional problem of the slaves.

Cheers,
Dom.
 
Ok. Just to give you a following (all the people who took the time to give some advices). I finally removed the brake master this morning. I probably found the source of the leak when I tried to remove the collar from the flexible hose in the front. I could unscrew the collar nut by hand. And there was fluid around the black washer where the nipple is enclosed. Also, I was expecting the fluid coming from where the rod enter the master, but the black boot was clean without fluid.

So I put my master on a vice, install 2 reservoirs upside with hoses to the nipples, and filled the reservoirs with fluid. Pumping the master allow fluid to exit from both lines (front and rear). Here is a picture of my bench test.

20200816_200928.jpg


I could not be sure 100% of the source of the leak, but there were no leaks on the bench and I cannot be sure how much pressure I will get at the exit of both lines, but fluid is circulating.

So my next step will be to test if I could get fluid from the reservoirs to the end of the flexible hoses, before I put them back on the nipples. I don't think there was any restrictions there.

Next, I will put air from a compressor on the lines to the calipers to see if air is circulating to the bleed screw.

I wonder if I should try to fill the solid lines with fluid (using a syringue?) before bolting them back to the block linked to the master.

Then, back to bleeding. I may try first the MightyVac tool and/or pedal pressure. But if no good results, maybe the pressure bleeding from the reservoir cap or using a bike tube.

Advices are always welcome.
 
DanielForest said:
I wonder if I should try to fill the solid lines with fluid (using a syringue?) before bolting them back to the block linked to the master.
Click to expand...
Now that you are sure that flluid is flowing through the master, leave them empty.

Before you reconnect them at the block by the master, disconnect the hard lines at the calipers and and try compressed air through them, just to be sure that they aren't blocked.

Then reconnect at the block by the master, add fluid at the reservoirr and watch it flow freely at the caliper end with just the influence of gravity (and if they don't then you've probably kinked/crushed the line from the reservoir, because the reservoir should be draining out through the open caliper ends). Pump the pedal to hurry things along if you want, but don't let the reservoir go dry or you'll have to start over.

As soon as you get a good flow at the end of each hard line connect it to its cailiper, and use your favorite bleeding technique from there.
 
EricH said:
Now that you are sure that flluid is flowing through the master, leave them empty.

Before you reconnect them at the block by the master, disconnect the hard lines at the calipers and and try compressed air through them, just to be sure that they aren't blocked.

Then reconnect at the block by the master, add fluid at the reservoirr and watch it flow freely at the caliper end with just the influence of gravity (and if they don't then you've probably kinked/crushed the line from the reservoir, because the reservoir should be draining out through the open caliper ends). Pump the pedal to hurry things along if you want, but don't let the reservoir go dry or you'll have to start over.

As soon as you get a good flow at the end of each hard line connect it to its cailiper, and use your favorite bleeding technique from there.
Click to expand...
Could I do it that way:
If I keep the hardline connected to the flex hose, connected to the caliper, any reason why there will be no air exiting by the bleed screw if I used compressed air from the hardline at the master? Then, if there is no air, I could check the flex hose, then the hardline.
 
DanielForest said:
Could I do it that way:
If I keep the hardline connected to the flex hose, connected to the caliper, any reason why there will be no air exiting by the bleed screw if I used compressed air from the hardline at the master? Then, if there is no air, I could check the flex hose, then the hardline.
Click to expand...
That works too, especially if you have a reason not to want to open the line at the caliper end. It’s just a bit slower to fill the line.
 
Good news! There is progress. I filled the brake reservoir with fluid and the 2 hoses hanging under the dash DID NOT dripped! They were not kinked. The grommet surroundind their entries to go under the dash compressed them too much. Probably the hoses got a slighlty bigger OD. As soon as I started fiddling with them, there was some brake fluid going to the end of the hose.

20200817_113502.jpg


I'm going to drill a new hole near them to pass the clutch hose alone. Grommets needed to avoid the hose rubbing on the holes gap.
 
You must log in or register to reply here.
Back
Top