Having Trouble Bleeding New Brakes

[hotcobra03]

another thing to look for...if you replaced any steel brake lines ,with a longer line and had to make a loop in the line,,,the loop must be facing down....(air trapped in loop)

have seen it before

 

[tx65coupe]

I'm glad your brought that up. What is a sufficient bore size for Granada front and Versailles rear with manual brakes?

I'm going to try to find out what the bore size is?

Thats a good point about the looped metal lines. I do actually have a line like that that goes to the SSBC adjustable proportioning valve. When you say the loop must be facing down, do you mean that it needs to be a verticle loop and not a horizontal loop?

I have read in another forum that the proportioning valve needs to be turned all the way clockwise to be fully open or to be inoperative. Is this true? My initial setup says to turn it all the way counter clockwise and the turn it a little bit clockwise. The user in the other forum said he had trouble bleeding his brakes until he turned the knob all the way in. That seems backwards to me.

 

[Rusty67]

You need to find the bore size of the calipers. There is a forumla to calculate it. I gota try and look it up again.

 

[Bullitt]

Thats a good point about the looped metal lines. I do actually have a line like that that goes to the SSBC adjustable proportioning valve. When you say the loop must be facing down, do you mean that it needs to be a verticle loop and not a horizontal loop?

You do not want vertical loops as they will create a highpoint for air. Horizontal loops shouldn't cause you any problems.

I have read in another forum that the proportioning valve needs to be turned all the way clockwise to be fully open or to be inoperative. Is this true? My initial setup says to turn it all the way counter clockwise and the turn it a little bit clockwise. The user in the other forum said he had trouble bleeding his brakes until he turned the knob all the way in. That seems backwards to me.

You want the proportioning valve set so that it has full pressure to the rear brakes. After you've bled the brakes you can screw it in (reducing pressure to the rear brakes) and back it off a few turns.

 

[Bullitt]

Another thought too...

Are you running a proportioning block of any sort in addition to the adjustable valve????

If so, you need to make sure that it's gutted and doesn't have any proportioning functionality. This is a step that a lot of people forget when they convert Fox mustangs to rear disk w/ adjustable valve and the brakes never work right if it isn't done.

 

[hotcobra03]

low pedal troubleshooting links

Diagnosing Spongy Brake Pedals: Solving Before Installing,Bill Williams, Brake & Front End, September 2004

http://www.carquest.com/common/downloads/partsTechBrakeCQB 00-06.pdf


brake system

 

[tx65coupe]

I'm not running a proportioning block. I do have a distribution block, but thats all it does. I do have a loop in each of the lines coming off of the MC but they are horizontal loops positioned like a front coil spring.

As far are turning the knob on the SSBC proportioning valve. Doesn't screwing it all the way in increase to give full pressure to rear brakes. That is what I was told by a couple of other people in another forum and I read that in a tech article. It seems backwards to me.

I screwed the knob all the way in and bled them again. I think all of the air is out now. I still think the pedal goes down too far.

I won't be able to test drive yet. The drivetrain is not all in the car yet. The engine went in tonight. The transmission is going in tomarrow. Then I have to wait for a driveshaft and a backordered radiator.

The bore size of the MC is about an inch. We measured it before installing it.

 

[tx65coupe]

Diagnosing Spongy Brake Pedals: Solving Before Installing,Bill Williams, Brake & Front End, September 2004

http://www.carquest.com/common/downloads/partsTechBrakeCQB 00-06.pdf


brake system

Thanks for the links. I'm going to read over them.

 

[hotcobra03]

bore sizes

i did a search and seen alot have the 15/16 bore..than they started 1 1/8 bore...

most showed upgrades with rear drum..than said can be used with 4wheel disc but with special mc for manual brakes,,but didnt see part number for mc...


in the one link i passed on it has the pinch off test....do that test..to see if mc is good,and it holds with a high pedal,,


this reminds me of a guy who made me learn fast,,,he would bring me 1950`s trucks and try to get them to work,,,, this is fun... had done this with books before the internet...now its even easier,,



i think you have a fluid return problem....calipers take more fluid than wheel cylinders..

than with the adjustable proportioning valve..i still think you need more between that and mc..to hold fluid from returning back into mc...this is what the pinch test will show...if you get a hard pedal than you have fluid flow problem.....

 

[markandjay]

no brakes

I put maverick disc on my car with lincoln t.c. 9inch w disc on back. I had to bleed 4 2 forevers!!! The best way I've found to do this is to buy some mason jars fill with fluid shove vac. lines on the bleeders pull top off m.c. and pump the brakes just keep an eye on your jars make sure to keep em full. and watch the fluid at the m.c. it will make a mess if it is not tended to. also remeber to close bleeders when finished it is all kinda backwards so it can be easily forgotten.

 

[Rusty67]

What did you measure the bore size with ? Don't use a measuring tape to check this as it wont be accurate. You need to use a caliper to check.

I wouldn't run anything larger then a 1" bore caliper if yer going to keep it manual. I have the SVO MC with a 1 1/8" bore and that pedal is ROCK hard. I'm going to be puting a booster in.

You should provably run a 15/16" bore or a 1" bore. You may have to play with it to find the right size for the pedal feel you desire. Remember, a larger bore will create a harder pedal with less travel. The smaller bore will make the pedal feel easier but the pedal will have to travel further before the brakes will actually work.