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JHop
Gents,

I have done the searches, watched some video, looked up stuff, rebuilt my calipers, replaced the MC, soft brake lines, and some hard lines, new pads and hardware, adjusted the venting clearance on the rear pads, speed bleeders...probably going on about $600 all in on this brake system so far...bled , then bled, then bled some more using a pressure bleeder...still a soft pedal and red blinky brake dash light when the pedal goes to the floor. I tried to do the pedal bleed, but it didn't seem like the fluid was moving. When I switched to the pressure bleeder, the fluid started coming out...no air bubbles.

What am I missing? Adjust the venting again? If I did that wrong, does it screw up the whole system? Car runs, is looking good...needs to STOP. headbang.gif
porschetub
Have you bleed off the calipers in the correct order i.e.furtherest to nearest from the m/c /,what brand of m/c did you buy?,is your brake pedal adjusted for correct stroke?.
Have you replaced the brake fluid,old shity stuff can wear out new parts in no time...ask me how I know.
Whole bunch of questions I know but I'am not in your garage to see whats going on.
Good luck.
JHop
QUOTE(porschetub @ Feb 14 2017, 05:21 PM) *

Have you bleed off the calipers in the correct order i.e.furtherest to nearest from the m/c /,what brand of m/c did you buy?,is your brake pedal adjusted for correct stroke?.
Have you replaced the brake fluid,old shity stuff can wear out new parts in no time...ask me how I know.
Whole bunch of questions I know but I'am not in your garage to see whats going on.
Good luck.


Hey there! Yeah, I did the correct order...not sure about the brake pedal...all new fluid. have an ATE MC...

Would it make sense to check the venting on the rears again? I'm so frustrated, I'm about to cave in and get it towed to my indy....I just want to fix it myself...
wndsrfr
QUOTE(JHop @ Feb 14 2017, 04:59 PM) *

Gents,

I have done the searches, watched some video, looked up stuff, rebuilt my calipers, replaced the MC, soft brake lines, and some hard lines, new pads and hardware, adjusted the venting clearance on the rear pads, speed bleeders...probably going on about $600 all in on this brake system so far...bled , then bled, then bled some more using a pressure bleeder...still a soft pedal and red blinky brake dash light when the pedal goes to the floor. I tried to do the pedal bleed, but it didn't seem like the fluid was moving. When I switched to the pressure bleeder, the fluid started coming out...no air bubbles.

What am I missing? Adjust the venting again? If I did that wrong, does it screw up the whole system? Car runs, is looking good...needs to STOP. headbang.gif

Did you "bench bleed" the MC before installing....if not, do it.
mepstein
QUOTE(wndsrfr @ Feb 14 2017, 09:46 PM) *

QUOTE(JHop @ Feb 14 2017, 04:59 PM) *

Gents,

I have done the searches, watched some video, looked up stuff, rebuilt my calipers, replaced the MC, soft brake lines, and some hard lines, new pads and hardware, adjusted the venting clearance on the rear pads, speed bleeders...probably going on about $600 all in on this brake system so far...bled , then bled, then bled some more using a pressure bleeder...still a soft pedal and red blinky brake dash light when the pedal goes to the floor. I tried to do the pedal bleed, but it didn't seem like the fluid was moving. When I switched to the pressure bleeder, the fluid started coming out...no air bubbles.

What am I missing? Adjust the venting again? If I did that wrong, does it screw up the whole system? Car runs, is looking good...needs to STOP. headbang.gif

Did you "bench bleed" the MC before installing....if not, do it.

Or crack the lines at the MC.
stugray
Do you have the calipers installed where the bleeders are at the top of the calipers?

And if you have any calipers with two bleeders, you are using the top ones?
JHop
QUOTE(mepstein @ Feb 14 2017, 06:50 PM) *

QUOTE(wndsrfr @ Feb 14 2017, 09:46 PM) *

QUOTE(JHop @ Feb 14 2017, 04:59 PM) *

Gents,

I have done the searches, watched some video, looked up stuff, rebuilt my calipers, replaced the MC, soft brake lines, and some hard lines, new pads and hardware, adjusted the venting clearance on the rear pads, speed bleeders...probably going on about $600 all in on this brake system so far...bled , then bled, then bled some more using a pressure bleeder...still a soft pedal and red blinky brake dash light when the pedal goes to the floor. I tried to do the pedal bleed, but it didn't seem like the fluid was moving. When I switched to the pressure bleeder, the fluid started coming out...no air bubbles.

What am I missing? Adjust the venting again? If I did that wrong, does it screw up the whole system? Car runs, is looking good...needs to STOP. headbang.gif

Did you "bench bleed" the MC before installing....if not, do it.

Or crack the lines at the MC.

Are you thinking I have air in the MC? Another thing...my brake lights are now on the minute I fire the car up...any clue? never seen that before.
JHop
QUOTE(stugray @ Feb 14 2017, 09:44 PM) *

Do you have the calipers installed where the bleeders are at the top of the calipers?

And if you have any calipers with two bleeders, you are using the top ones?


Yes, the rears have the two bleeders, and I've only used the top ones...still no pedal at all.

Man, I just want to be able to drive this car...it's killing me. If there is anyone in the Portland, OR area that can help me I'll be forever grateful!
dlee6204
QUOTE(JHop @ Feb 15 2017, 12:46 AM) *

QUOTE(mepstein @ Feb 14 2017, 06:50 PM) *

QUOTE(wndsrfr @ Feb 14 2017, 09:46 PM) *

QUOTE(JHop @ Feb 14 2017, 04:59 PM) *

Gents,

I have done the searches, watched some video, looked up stuff, rebuilt my calipers, replaced the MC, soft brake lines, and some hard lines, new pads and hardware, adjusted the venting clearance on the rear pads, speed bleeders...probably going on about $600 all in on this brake system so far...bled , then bled, then bled some more using a pressure bleeder...still a soft pedal and red blinky brake dash light when the pedal goes to the floor. I tried to do the pedal bleed, but it didn't seem like the fluid was moving. When I switched to the pressure bleeder, the fluid started coming out...no air bubbles.

What am I missing? Adjust the venting again? If I did that wrong, does it screw up the whole system? Car runs, is looking good...needs to STOP. headbang.gif

Did you "bench bleed" the MC before installing....if not, do it.

Or crack the lines at the MC.

Are you thinking I have air in the MC? Another thing...my brake lights are now on the minute I fire the car up...any clue? never seen that before.


We are absolutely thinking you have air in the system. So did you crack the lines at the master cylinder and bleed it? The brake light being on is likely a simple fix of the actuating rod engaging the brake switch at the pedal cluster.

Typically on a new system, the very first thing I do is crack one of the lines at the MC and pump the pedal until fluid comes out. I close one line and crack the other and repeat. After bleeding both lines at the MC, I then crack one line after the proportion of valve and pump til fluid comes out. I then proceed to all four wheels and bleed. I drive the car and then bleed again. Seems to work pretty well.
JHop
QUOTE(dlee6204 @ Feb 15 2017, 04:45 AM) *

QUOTE(JHop @ Feb 15 2017, 12:46 AM) *

QUOTE(mepstein @ Feb 14 2017, 06:50 PM) *

QUOTE(wndsrfr @ Feb 14 2017, 09:46 PM) *

QUOTE(JHop @ Feb 14 2017, 04:59 PM) *

Gents,

I have done the searches, watched some video, looked up stuff, rebuilt my calipers, replaced the MC, soft brake lines, and some hard lines, new pads and hardware, adjusted the venting clearance on the rear pads, speed bleeders...probably going on about $600 all in on this brake system so far...bled , then bled, then bled some more using a pressure bleeder...still a soft pedal and red blinky brake dash light when the pedal goes to the floor. I tried to do the pedal bleed, but it didn't seem like the fluid was moving. When I switched to the pressure bleeder, the fluid started coming out...no air bubbles.

What am I missing? Adjust the venting again? If I did that wrong, does it screw up the whole system? Car runs, is looking good...needs to STOP. headbang.gif

Did you "bench bleed" the MC before installing....if not, do it.

Or crack the lines at the MC.

Are you thinking I have air in the MC? Another thing...my brake lights are now on the minute I fire the car up...any clue? never seen that before.


We are absolutely thinking you have air in the system. So did you crack the lines at the master cylinder and bleed it? The brake light being on is likely a simple fix of the actuating rod engaging the brake switch at the pedal cluster.

Typically on a new system, the very first thing I do is crack one of the lines at the MC and pump the pedal until fluid comes out. I close one line and crack the other and repeat. After bleeding both lines at the MC, I then crack one line after the proportion of valve and pump til fluid comes out. I then proceed to all four wheels and bleed. I drive the car and then bleed again. Seems to work pretty well.

Thanks for the help guys! I'll try the above and take a look at the actuating rod as well. I'll let you know what happens. I've done a bunch of MC exchanges before, but this one has just been a real challenge!
tomeric914
Check your brake hoses. If they are 40+ years old, they will be constricted.

I ran across a situation recently where the internal bleed passageway down to one side of the caliper bores was blocked with crud/rust so only one side of the caliper was able to bled. The result was spongy to no brakes.

I had to split the caliper and run a wire or very small drill through the passageway to clear it out. With the passageway clear, the brakes bled normally and I had a solid pedal.

While the image below is of a bicycle caliper, the idea of the passageways is similar to how our calipers passageways are run. If they aren't clear, the caliper won't bleed.

IPB Image
6freak
i recalL someone saying something along the lines of .. if you push the peddle to far down you can damage an o ring or seal in the M/C IIRC there for not being able to build pressure good luck smile.gif IMO its the M/C
McMark
You absolutely, undeniably MUST bleed the master cylinder before hooking up your brake lines. This can be done on a bench or it can be done in the car.

You need three caps to plug the outlet lines on the MC. You can make these by getting some cheap bubble-flare brake lines from your local auto parts store. Cut the ends off, crimp the cut end of the hardline, the heat with a torch and drop some plumbing solder down the tube. Viola! Brake line plug.

Make three of those and install them in the outlet ports of the MC. Then just pump the pedal until is gets ROCK solid. Not kinda solid. Not mostly solid. Not a little bit firm. Keep going until it's SOLID. (well there may be a bit of free play at the top/initial movement depending on how your pedal plunger is adjusted).

Once the MC is solid, have someone sit in the car and press the pedal and keep it down while you remove the plugs and install the real brake lines. With the pedal down the fluid from the reservoir won't spill all over.

Or for an even better bleeding experience, hook up just the rear lines first, leave the caps in the front and bleed the rears until they're rock solid. Then add one of the fronts and bleed that until rock solid. Then add the last front and finish bleeding.

It's a pain in the ass, but you're driving yourself crazy because you're doing it completely wrong. Take a break (laugh.gif) and then come back and attack it correctly.

You can do it. thumb3d.gif
McMark
Wrote up a tutorial on building the brake line plugs you need.
http://www.914world.com/bbs2/index.php?showtopic=304882
Spoke
QUOTE(JHop @ Feb 15 2017, 12:46 AM) *

Another thing...my brake lights are now on the minute I fire the car up...any clue? never seen that before.


This may be a clue to why you have no brakes. This means your brake pedal is always depressed. It might be the mechanical connection between the pedal and the MC. Have you taken the pedal board out and inspected the connection from the pedal to the MC?

When the pedal board is out, you can see the brake switch which lights the brake lights. There may be an adjustment necessary or something isn't lined up properly.
Dave_Darling
The brake lights are triggered by a switch on the pedal cluster. The switch is spring-loaded in the "brake lights on" position. The switch is pressed by a washer on the pushrod that goes from the pedal to the master cylinder; when the pedal comes back up it pushes on the arm of the switch and breaks the circuit turning the brake lights off.

It is easy to get the arm of the switch on the wrong side of the washer, which will lead to brake lights on all the time.

The brake warning light coming on is happening because the pedal is going to the floor. That's one of the functions of the warning light.


You still have air in the system somewhere, or fluid is bypassing the seals somewhere in the system.

Brake lines will not cause you to have no pedal unless they are letting air in, at which point they will also be letting fluid out and you'll generally find leaked-out fluid.

--DD
malcolm2
I bet the MC has a split seal. New or not it sounds like the MC is not building pressure. I had the same issue. Searched everywhere, fixed everything. Took the MC out. Took it apart and there is was. Mine was a 17mm so I could not find parts. Just bought another.

Won't hurt to take it apart and look at it.
TheCabinetmaker
What brand, and where did you buy said master cylinder? I put 4 master cylinders on my truck before I got one that worked.
JHop
QUOTE(The Cabinetmaker @ Feb 15 2017, 01:57 PM) *

What brand, and where did you buy said master cylinder? I put 4 master cylinders on my truck before I got one that worked.


Bought the MC from local import auto place that specializes in VW/Porsche. FTE was what it said on the box...I hope I'm not going through that many... sad.gif
jsaum
QUOTE(JHop @ Feb 14 2017, 09:49 PM) *

QUOTE(stugray @ Feb 14 2017, 09:44 PM) *

Do you have the calipers installed where the bleeders are at the top of the calipers?

And if you have any calipers with two bleeders, you are using the top ones?


Yes, the rears have the two bleeders, and I've only used the top ones...still no pedal at all.

Man, I just want to be able to drive this car...it's killing me. If there is anyone in the Portland, OR area that can help me I'll be forever grateful!

And your front calipers have the bleeders on top too? It took me a week to figure out I had them on the wrong sides. I ran three large bottles of fluid through while trying to bleed the system. Once I switched them I had a firm pedal in minutes! Oh and I now have a really cleanly flushed out brake system! Hang in there you'll figure it out.
Jsaum
porschetub
The above reply made me laugh couldn't get my brembo 4 pots right until I found a second bleeder on my rear of the calipers,felt silly about that....a quick bleed on each of the rear ones (front was ok) got me a lovely firm pedal.
OP hasn't mentioned venting off the m/c yet sounds airlocked to me ,hope the seals are still ok dry.gif
Peashooter
I had a bad seal in the m/c as well. Moved fluid but couldn't get a good pedal. A lot of them have been sitting on the shelf for years and the seals dry up and split when pressure is applied.
JHop
QUOTE(jsaum @ Feb 16 2017, 07:51 PM) *

QUOTE(JHop @ Feb 14 2017, 09:49 PM) *

QUOTE(stugray @ Feb 14 2017, 09:44 PM) *

Do you have the calipers installed where the bleeders are at the top of the calipers?

And if you have any calipers with two bleeders, you are using the top ones?


Yes, the rears have the two bleeders, and I've only used the top ones...still no pedal at all.

Man, I just want to be able to drive this car...it's killing me. If there is anyone in the Portland, OR area that can help me I'll be forever grateful!

And your front calipers have the bleeders on top too? It took me a week to figure out I had them on the wrong sides. I ran three large bottles of fluid through while trying to bleed the system. Once I switched them I had a firm pedal in minutes! Oh and I now have a really cleanly flushed out brake system! Hang in there you'll figure it out.
Jsaum

Yeah, the calipers are correct...just pressurized the system with the presssure bleeder...firm pedal! So, what does THAT mean?

JHop
QUOTE(Peashooter @ Feb 17 2017, 12:53 PM) *

I had a bad seal in the m/c as well. Moved fluid but couldn't get a good pedal. A lot of them have been sitting on the shelf for years and the seals dry up and split when pressure is applied.


SUCCESS! Took getting my buddy to help out, but we finally got a firm pedal...combination of pressure bleeding, vac bleeding and old fashioned pedal work. Of course, a 914 firm pedal still could use some work... smile.gif

Off to have a beer! beer3.gif

Thanks to everyone for your advice! Great forum!

John
jsaum
Congrats! It's a frustrating battle but the victory is great!
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