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> Brakes won't pump up, Bad master cyl.?
toon1
post Feb 21 2013, 10:03 PM
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I just completed the 5 lug conversion on the front and I can't get any brake pedal pressure. I've bled the system from the back pass. first, driver rear second, front pass. third and front driver last. I have clear fluid all the way through the system and no bubbles.

The front calipers are rebuilt with all new seals.

I pressed on the pedal slowly with the bleeder valve open and can see fluid moving towards the catch bottle.

There are no leaks anywhere.

I'm stumped, I'm wondering if the master went bad somehow and it wont build pressure.

They worked great before the conversion.
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mrbubblehead
post Feb 21 2013, 10:37 PM
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try and bleed the master cylinder first. have someone put pressure on the brake pedal and crack open the fittings on the master cylinder a couple times. then you should be able to go to the calipers.
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Mark Henry
post Feb 21 2013, 10:49 PM
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QUOTE(mrbubblehead @ Feb 21 2013, 11:37 PM) *

try and bleed the master cylinder first. have someone put pressure on the brake pedal and crack open the fittings on the master cylinder a couple times. then you should be able to go to the calipers.

(IMG:style_emoticons/default/agree.gif)
Makes a mess but crack the fittings just like you would a bleeder screw, if you still have a proportion valve do it there as well.
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Cap'n Krusty
post Feb 21 2013, 10:49 PM
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You're gonna have that problem with rebuilt calipers, and putting a bunch 'o miles on it will probably fix the problem. BTDT, many times.

The Cap'n
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toon1
post Feb 21 2013, 10:59 PM
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I'll try bleeding the master cyl. .

will it still work even if there is NO pedal pressure?
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mrbubblehead
post Feb 21 2013, 11:19 PM
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QUOTE(toon1 @ Feb 21 2013, 08:59 PM) *

I'll try bleeding the master cyl. .

will it still work even if there is NO pedal pressure?


yes, push the pedal to the floor, crack the fitting, release pedal. repeat.

after 2, 3,or 4 times, you should start to feel the pedal get harder. you should probly do all 3 fittings. i dont think the brake electrical fitting is necessary.

like mark said it kinda messy. throw a rag around the MC so you dont spray brake fluid all over. safety glasses probly wont hurt either. make sure you wash the sprayed brake fluid with soap and water right away.
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McMark
post Feb 22 2013, 10:36 AM
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I'd go to the parts store and get a couple of short lengths of brake hard line. Cut 1/2" to 1" of tube and crimp the end flat. Then solder or epoxy the center tube shut. You want no air leaks and it has to stand up to pressure.

Then install these new plugs into the connections on the master cylinder (there's three). With everything sealed up, jump in the car and pump the pedal until it's absolutely rock hard. I can't emphasize that enough don't stop until the pedal doesn't move (aside from the gap between the pedal pushrod and the MC internals). You'll have to top off the fluid a few times. Also do different movements-- full strokes, short bursts, simply tapping the pedal with your foot. All these things will cause bubbles to burp out the reservoir.

Once it's completely bled out, hook up the calipers and bleed those. You either need to be quick when swapping the plugs for the lines, or have someone step on the brake pedal. Having the pedal pushed down will block off the reservoir feed lines and keep the MC and reservoir from draining. There will be a squirt of fluid when you open the first connection, but if the helpe doesn't move their foot, it won't drip any more fluid after that.
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McMark
post Feb 22 2013, 10:37 AM
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Also, search for the long tube method.
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Eric_Shea
post Feb 22 2013, 11:17 AM
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...or:

(IMG:http://www.914world.com/bbs2/uploads_offsite/www.pmbperformance.com-1110-1361553438.1.jpg)
http://www.pmbperformance.com/catalog/item...563/9748923.htm

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http://www.pmbperformance.com/catalog/item...563/9748903.htm

(IMG:style_emoticons/default/biggrin.gif)
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ChrisFoley
post Feb 22 2013, 11:54 AM
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Or grab two old brake hard lines from a parts car and do what McMark recommended - for free. (IMG:style_emoticons/default/laugh.gif)
I TIG weld the crimped tubing shut.
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Eric_Shea
post Feb 22 2013, 02:38 PM
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Unless you value your time. (IMG:style_emoticons/default/biggrin.gif)
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mrbubblehead
post Feb 22 2013, 02:42 PM
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QUOTE(Racer Chris @ Feb 22 2013, 09:54 AM) *

Or grab two old brake hard lines from a parts car and do what McMark recommended - for free. (IMG:style_emoticons/default/laugh.gif)
I TIG weld the crimped tubing shut.

i'm not understanding (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/confused24.gif)
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mrbubblehead
post Feb 22 2013, 02:44 PM
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QUOTE(McMark @ Feb 22 2013, 08:36 AM) *

I'd go to the parts store and get a couple of short lengths of brake hard line. Cut 1/2" to 1" of tube and crimp the end flat. Then solder or epoxy the center tube shut. You want no air leaks and it has to stand up to pressure.

Then install these new plugs into the connections on the master cylinder (there's three). With everything sealed up, jump in the car and pump the pedal until it's absolutely rock hard. I can't emphasize that enough don't stop until the pedal doesn't move (aside from the gap between the pedal pushrod and the MC internals). You'll have to top off the fluid a few times. Also do different movements-- full strokes, short bursts, simply tapping the pedal with your foot. All these things will cause bubbles to burp out the reservoir.

Once it's completely bled out, hook up the calipers and bleed those. You either need to be quick when swapping the plugs for the lines, or have someone step on the brake pedal. Having the pedal pushed down will block off the reservoir feed lines and keep the MC and reservoir from draining. There will be a squirt of fluid when you open the first connection, but if the helpe doesn't move their foot, it won't drip any more fluid after that.
i'm not understanding (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/confused24.gif)
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Chris H.
post Feb 22 2013, 02:57 PM
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This happened to me last year...I hate to even admit how simple the fix was...did you bleed the top and bottom bleeders on all wheels that have them? I forgot the upper back ones when changing the fluid and MC. Fixed it immediately after those were opened...
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toon1
post Feb 22 2013, 03:13 PM
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QUOTE(Chris H. @ Feb 22 2013, 12:57 PM) *

This happened to me last year...I hate to even admit how simple the fix was...did you bleed the top and bottom bleeders on all wheels that have them? I forgot the upper back ones when changing the fluid and MC. Fixed it immediately after those were opened...


There is only one bleeder on my caipers.

Thanks for all the suggestions guy's. I'll try them and let you know what I find.
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ChrisFoley
post Feb 22 2013, 03:18 PM
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QUOTE(mrbubblehead @ Feb 22 2013, 03:42 PM) *

i'm not understanding (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/confused24.gif)

We're using the brake line fittings as plugs by sealing the cut off end of the line.
Eric's picture is the cap for a rear caliper inner adjuster - same threads.
I like the line fittings better for a pressure application because they have the tapered seat.
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ArtechnikA
post Feb 22 2013, 04:43 PM
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QUOTE
There is only one bleeder on my calipers.

Gotta ask - because there are no pictures - you've got 'em mounted with the bleeders up, yes ? Right on the right, left on the left ?

You wouldn't be the first...

There's brake-port-plugs with the conical seats.
Once upon a time I knew the VW part number.
I'll try to post a picture tonight - but Feb 22 is National Margarita Day so I can make no promises :-)
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toon1
post Feb 22 2013, 05:14 PM
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QUOTE(ArtechnikA @ Feb 22 2013, 02:43 PM) *

QUOTE
There is only one bleeder on my calipers.

Gotta ask - because there are no pictures - you've got 'em mounted with the bleeders up, yes ? Right on the right, left on the left ?

You wouldn't be the first...

There's brake-port-plugs with the conical seats.
Once upon a time I knew the VW part number.
I'll try to post a picture tonight - but Feb 22 is National Margarita Day so I can make no promises :-)



You may be the winner! the bleeders are on the bottom. Didn't notice that.

I dissconnected the lines from the MC and plugged them. The MC is rock solid.
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ChrisFoley
post Feb 22 2013, 06:07 PM
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QUOTE(ArtechnikA @ Feb 22 2013, 05:43 PM) *

= you've got 'em mounted with the bleeders up, yes ? Right on the right, left on the left ?

Good catch!
QUOTE

I'll try to post a picture tonight - but Feb 22 is National Margarita Day so I can make no promises :-)

Really?
I didn't know that but...
Maybe that's why I had the irresistible urge to mix a Margarita as soon as I got home from work. (IMG:style_emoticons/default/beer3.gif)
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ArtechnikA
post Feb 22 2013, 06:40 PM
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QUOTE(ArtechnikA @ Feb 22 2013, 05:43 PM) *

I'll try to post a picture tonight...

Well - there is no Cointreau nor Triple Sec so we'll have to have two 'ritas tomorrow.
Meanwhile I am drinking my Cabo Wabo Blanco (it was on sale...) neet.
Was able to get this pic tho...
Interestingly, the conical part is on the _inside_. But they have served me well through several 'partial brake install' adventures...
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