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Discussion Starter #1
Replacing the brake booster. I'll be able to remove/re-install the brake master cylinder and bleed the line. Since the clutch master cylinder is attached to the booster looks like that will have to come off as well and be bleed after re-attach. Question is where does the line from the clutch master cylinder end so I can bleed the line?
 

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Discussion Starter #3
Thanks for the reply! Where in the transmission is the slave cylinder located? Hoping the bleed nozzle is accessible without getting in the transmission...
 

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But Mad North-Northwest
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Slave is on the right front of the transmission. Follow the hose, it's accessible from below the car for bleeding.

Having done this a couple times, I'd recommend removing the pedal box as an assembly and doing the booster job on the bench. You'll need to disconnect the brake and clutch master cylinder fittings and bleed both systems but that's not very hard.

Disconnect the hydraulic fittings at both MCs, take off the brake/clutch pedal rubber pads, remove four nuts, and you can lift the whole pedal box assembly out of the engine bay (rotate it a bit to get it around the steering shaft).

Make sure you properly set the new booster pin length on the bench to match your old one. If you haven't done it, this is also a good opportunity to replace your clutch pivot lever with one of the upgraded ones. The original ones are weak and prone to breaking at the weld.
 

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Discussion Starter #5
would love to see what the pedal box looks like. photo or diagram. it's been mentioned before. Have read some posts that say you can use a universal joint socket and not need to take the pedal box out to release the booster. as for bleeding the brake lines, do you need to bleed each caliper?
 

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But Mad North-Northwest
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You're in luck, I took a photo. There are two nuts in the top in the engine bay, then two in the driver's footwell, and then it comes out as an assembly with a little lifting and rotating. Personally I find it a lot easier than trying to get the booster out under the dash, and you can easily upgrade your clutch pivot at the same time. I'm sure some folks prefer to do it without removing the pedal box or the MC connections.

Yes, if you disconnect the MC connections you need to bleed at each caliper. When you reconnect the fittings loosen both MCs from their attachment points so you can get them lined up properly and start the threads by hand, this avoids the risk of cross threading.


1645384
 

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But Mad North-Northwest
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Yep, you can see them if you look at the backside of the pedal box from the footwell. You can take it out via those nuts, some people do, but I just take the whole thing out and do the job on the bench.
 

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Discussion Starter #9
Wow, I have no idea how you can reach the screws to release the booster with the peddle box in... As for the brake fluid in the second chamber, does that drain out when the fitting is released?
 

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But Mad North-Northwest
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Yes. The reservoir is divided front to back with a half-height divider. This is so if one half of the system springs a leak the MC will still retain fluid for the other half to work. When you remove the line to the rear brakes, the fluid in the rear half of the MC will dribble out.

The issues with getting to the booster under the dash are why I just pull the pedal box, yes. The two bottom nuts holding the pedal box in are pretty easy to get to.
 

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But Mad North-Northwest
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Also note that if you find any fluid in your booster the brake MC is leaking from the rear and needs to be replaced. This is the main reason the boosters fail: the rubber sits in brake fluid for a while and dies.
 

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Discussion Starter #12
Peddle box is out and on the bench. Is there a correct method for removing the clutch master to not lose the adjustment?
 

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But Mad North-Northwest
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The length should be locked with a nut. Just remove the clevis pin and the two bolts and pull it out, it'll be fine.
 

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Discussion Starter #14
I guess you just squeeze through the rubber cover on the clutch master.

Took your advice and got a new brake master. May as well.

Is there a trick for adjusting the rod on the new booster?

Thanks so much for the help!
 

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But Mad North-Northwest
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Not sure what you mean? The rubber cover is attached to the clutch MC. It should all come off as one piece when you remove the pin and two bolts.

The booster rod needs to be very close to the MC piston face but not touching. There are tools available to set it correctly. In my experience the MCs are generally the same so if you set it to be the same length as your old booster it works okay, but you should take some measurements and do a test fit to verify this. This is another thing that's much easier to do with the assembly off the car.
 

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Discussion Starter #16
I don't feel any pressure when I put the master cylinder onto the booster. both push rods are at the same position as the they relate to the opening...
 

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Discussion Starter #17
I don't feel any pressure when I put the master cylinder onto the booster. both push rods are at the same position as the they relate to the opening...

The distance from the inner back plate to the opening is different between the two. But, again the rod position is the same in relation to the opening. Really just want to get it right. Cant image having to remove, adjust and bleed the lines again!
 

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But Mad North-Northwest
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I don't know any brilliant way to verify it, maybe someone else will join in. I just took some careful measurements with a plunge micrometer. There are tools to measure it right but I don't have one.

1645519


If you push the rod from the pedal side you may be able to feel it make contact with the MC. Or maybe you could use a piece of modeling clay or something to see what the clearance is.
 

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Discussion Starter #19
In your opinion, what is the critical measure? Is it the distance of the push rod protrusion past the plain of the booster? Seems that would be the case s the MC is standard...
 

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But Mad North-Northwest
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The critical measure is the end of the pin to the rear of the MC piston. You want a slight gap there. This site has a photo and shows how the tool is used.


Like I said, I guesstimated it using a plunge micrometer. If you search Google for "brake booster pin adjustment" you may find other methods.
 
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