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Discussion Starter · #1 ·
One of those again!!We Rodders get them from now and then,as you well know,so here goes......had a leaking servo on my Pop,so got a new one( had no numbers on it at all so 15 hrs on ebay etc and found a Victor 101 that was new and same size!)Anyway master cylinder had to be removed so we got the usual rounded head fittings.I was going to change the cylinder just to keep everything new but could nt find one like it and after trawling for several days on computer. ,gave up and stripped it down to get seal numbers,which I actually got.Rebuilt master cylinder and took rear brake pipes off to. Have new ends/fittings put on.(Did nt want to take front pipe off,there are pipes to each wheel so Master cylinder is a 4 pot,,as it looked like a nightmare to remove so bought a sealer DIY flare kit and tried to do it in situ).What a job!Tried about 12 times to get double flare and in the end gave it my best shot.........not too bad a flare but not brilliant.Put it all back together today and with wife on the pedal tried bleeding,near side front first,air and fluid flew out .......next off side front,no problem,then rears and this I'd where PROBLEM started.....no fluid coming out,then eventually a bit after almost screwing nipple out,no not the wife's!,so back to near side front....no fluid coming out,same on the other side,pumped pedal for ages tried nipples.....no fluid coming out.Pedal goes hard when motor is run then turned off so servo works but with motor running pedal goes to floor!no brakes?So what's going on?Is master cylinder knackered after initial pumps? Is it something to do with my duff flares on two of the pipes going into master cylinder?Are these stopping fluid from being pumped out of cylinder?Can t think what it can be,anyone any ideas?"?................
 

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That's because you should have bled the rears first on a dual circuit the rear most on the servo is the rear and the way it couples and pushes each piston inside means it a pig to bleed if you do it in the wrong order. Either drain down one of the front calipers or use a pressure bleeder should fix it.
 

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Discussion Starter · #3 ·
That's because you should have bled the rears first on a dual circuit the rear most on the servo is the rear and the way it couples and pushes each piston inside means it a pig to bleed if you do it in the wrong order. Either drain down one of the front calipers or use a pressure bleeder should fix it.
. Thanks for info BUT what I can t understand is on the master cylinder there are 4ports .The front ports,those nearest to servo,the r/h one serves the R/h front wheel and the l/h one serves the l/h rear and on the two rear ports the r/h one serves the right rear and the l/h one serves l/h front,now is that right?
 

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What is the m/c from as thy went through a period of using diagonally split brakes systems instead of front to rear .However it needs to be connected as per the donor car as they have built in pressure limitation . If it's that sort of system then you bleed the pipes connected to the m/c ports nearest the servo first.
 

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Discussion Starter · #5 ·
What is the m/c from as thy went through a period of using diagonally split brakes systems instead of front to rear .However it needs to be connected as per the donor car as they have built in pressure limitation . If it's that sort of system then you bleed the pipes connected to the m/c ports nearest the servo first.
Ok the MC was on the pop when I bought it and it is a diagonal system.After days of investigation I still can't find out what its from.The R/H rear and L/h rear are nearest,then R/H front and L/H front,so this is how Ill bleed them. Tomorrow. thanks
 

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Sorry might not have been clear enough. yYou need to bleed them as attached so that chamber is free of air so , if I understand above , you'll need to do rh front lh rear to clear that first port :)
 

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Discussion Starter · #7 ·
OH SO we clear the ports of air in sequence,what a bloomin pulava this is,I ll give it a go tomorrow. Thanks for the help
 

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The front and rear ports have emergency interlinks when they fail but to get them to travel full stroke you need to get the back one ( nearest the servo ) totally empty of air so it can push the front one fully. Otherwise because they are in emergency mode they simply let the air bubble recycle . I'd drain the other front caliper to make life easier :)
 

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Discussion Starter · #11 ·
Reply to Kari......how can I drain front calliper when I take bleed nipple out completey and. Nothin comes out except a drop?
 

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hi kev, i know you've been involved with brakes a lot but i've always bled from the corner nearest to the master and worked away. never had any issues that way even with diagonally split systems like mk3 escorts. however if the master has been replaced/rebuilt i bleed that first (as the yanks recommend with all their master cylinders), i usually loosen the pipes at the master and get a mate to push and hold the pedal down. tighten pipes, lift pedal and then repeat 'til fluid comes out of all ports. then i bleed at the wheels.
at least if you try bleeding the master you'll know if it's that or your flares at fault.
 

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Discussion Starter · #13 ·
sounds good to me,so tomorrow I'll bleed MC first then each port in sequence"........going to bed now but keep em coming,thanks y all"
 

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Hi

I'm no expert and this was the first time I had done this. I've just completely installed a new brake system on my Chevy truck including new lines.

I bled the master cylinder before I put it on the truck. The master cylinder came with some little plastic threaded ports with some plastic tubing to pump the brake fluid back into the top of the master cylinder until no more bubbles came through.

I then bled from the furthest away from the master cylinder at the rear then worked forward. I had to go through the bleeding process twice to clear all the air completely just to make sure. If you are still not getting fluid at the rear try just opening the bleed screw at the furthest away and let gravity do its work for an hour or 2 this is how the yanks do it sometimes.

I also used one of those flaring kits and they are a bit of a nightmare, you find the flaring tool wears after a coupe of uses and doesn't go down square. The last couple I took to a local mechanic who had a proper flaring tool and it literally took him seconds to do them he didn't charge me anything for it as it was that quick. I would just do that if one of the flared lines turns out to be the cause instead of messing round with a cheap flaring tool that you need 3 pairs of hands to use.

Have patience I'm sure you will figure it out.
 

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hi kev, i know you've been involved with brakes a lot but i've always bled from the corner nearest to the master and worked away. never had any issues that way even with diagonally split systems like mk3 escorts. however if the master has been replaced/rebuilt i bleed that first (as the yanks recommend with all their master cylinders), i usually loosen the pipes at the master and get a mate to push and hold the pedal down. tighten pipes, lift pedal and then repeat 'til fluid comes out of all ports. then i bleed at the wheels.
at least if you try bleeding the master you'll know if it's that or your flares at fault.
I know most people do it that way Neil. However bleed sequences do differ on different cars and sometimes it can make all the difference. Power bleeder will overide all that though but I'm talking manual bleeding. You'll have taken enough cylinders apart to know what I'm talking about with the pressure in the rearmost portion driving the furthest one forward.

Good idea on bleeding the m/c though I'm normally don't as I guarantee the fluid will end up on a nicely painted engine bay!
 

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Discussion Starter · #16 ·
HI just bought a vacuum bleeder kit and although the wife won't let me in the garage today(she wants me all to herself on Sundays! don't ask) I managed to sneak in and try it out on one of the wheels,wow loads of air and fluid pouring out,when there was nothing before,anyway will use it properly tommorow..................
 
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