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Old 10-13-2013, 10:36 PM
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gcthree
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Default What Is It?

I know others have somehow wiggled their hands into the abyss and managed to change the clutch master cylinder with all systems in place, I took (what I thought) was the easy route by removing the brake booster and doing a general clean-up while I was at it.

In cleaning the reservoir, there is a rubber cover over a spring loaded 'switch' that you can depress. Here it is without the rubber cover. What is it, and what do it do?
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Old 10-13-2013, 10:43 PM
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Jadz928
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When you pulled the booster, did you push in the brake and secure the MC rod w/a clamp plate?

Last edited by Jadz928; 10-13-2013 at 11:01 PM. Reason: removed wrong info
Old 10-13-2013, 10:48 PM
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ammonman
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Test button for the low brake fluid warning switch. Press for 20 seconds and the "Low Brake Fluid" warning light should light up.

Mike
Old 10-13-2013, 11:00 PM
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Wow. I was way off. Learn something new everyday!
Old 10-13-2013, 11:03 PM
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gcthree
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Jim, I'm going with Mike's test switch answer. Sounds right to me.

Yes, I did push in on the brake pedal and secure it with a clamp...which flew off the minute I released the brake pedal. So, I clamped the rod with a small set of Vice Grips, and took 2 swipes at it per the WSM. It still was a couple of mm protruding too much to allow me to rotate the booster out.

So, I used a screw driver behind the Vice Grips to exert just a little more pressure and that got me what I needed. Not elegant, but it worked.

What is really needed is a threaded shaft on the booster that allows you to pull the rod out. How do we do that, Jim?

Here's a couple of photos:
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Old 10-13-2013, 11:06 PM
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Bilal928S4
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Doesn't that muck up the rod?
Old 10-13-2013, 11:10 PM
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gcthree
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Hardened steel, Bilal. Didn't leave a mark, but the clamp on the rod shot-off and wouldn't grip.
Old 10-13-2013, 11:15 PM
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Jadz928
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Originally Posted by gcthree
...

So, I used a screw driver behind the Vice Grips to exert just a little more pressure and that got me what I needed. Not elegant, but it worked.

What is really needed is a threaded shaft on the booster that allows you to pull the rod out. How do we do that, Jim?

Here's a couple of photos:
Search me. I'm trying to figure out how to paint the booster w/o removing the plate.
Old 10-13-2013, 11:21 PM
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Mrmerlin
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to pull the booster rod out,
simply get a piece of gas line hose slide it onto the rod then get the vice grips and clamp it ,
it wont move till your ready and no marks on the rod.

Ahh the other point to remember is that the seating surface of the MC to the booster is a precision fit ,

and if you scratch this surface then you may find your brakes wont work as well as they should,
since you will have effectively created a vacuum leak to the booster.
There is also a rubber seal thats in between the booster and MC but a scratch will make the seal difficult
Old 10-13-2013, 11:22 PM
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gcthree
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I'm going to work-up a bracket for the rear of the booster. I'll source parts tomorrow and cobble it together. If it works, I'll shoot it up to you.

I has a small spot of surface rust on the bottom of the booster, and after sand/prime, I hit it with the Eastwood Chassis Black and now it's clear that the whole booster will look amazing painted. Like you, I need to get that plate off to do it right.

Bob
Old 10-13-2013, 11:25 PM
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gcthree
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Now, why didn't I think of that.... probably could use the clamp, too.

Originally Posted by Mrmerlin
to pull the booster rod out,
simply get a piece of gas line hose slide it onto the rod then get the vice grips and clamp it ,
it wont move till your ready and no marks on the rod



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