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Spoke to brake guy again.

He said based on what I've said the booster sounds fine to him and if it was never firm before hand (with the same brakes) it shouldn't be firm now.

He suspects my adjustment of the rod to re-position the pedal might be the issue and has given me some notes on checking rod to master clearances, there should be some travel on the pedal and I'd say there's little if any.

I'll take a look. That might help the initial pedal firmness but I can't see how it will help how it feels once the booster rod comes in contact with the master.

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Yeah I don't know mate, I'm no brake expert I was just making the point that I don't think it's the pads based on my experiences with them/what you said.

Throw those spare pads at it and adjust master rod and test. Those are the only easy options bar testing a different BM.

I run the same pads and have punished them at track, just had the fluid get too hot replace fluid, bled and punished them again, never a hard pedal...

I dont thinks its pads either

The booster itself has been tested with and without Vac, and behaves as expected.

I'll test the pedal without it, but really that's no different to me pumping the pedal then holding it down and starting the car.

I'm hoping to get a few mins tonight and I'll focus on the booster rod length I think.

Well still confused.

I wasn't 100% clear on what he actually wanted me to measure, but I can say the rod on the booster has clearance to the master and is not hard up against it.

What I did find is that with the booster removed from the car and my finger over the fitting where the vac hose would connect. I could operate the booster by hand (which I thought he said I shouldn't be able to do but I'm not sure if he went with it on or off the car).

Either way, when the rod extends out the front I can feel air moving past the rod which I would assume is supposed to be air tight.

I have it with me and will drop past the brakes place tomorrow to discuss.

GTSBoy said he would put money on air leak from booster.

I said booster

We weren't just guessing. I've had the complete opposite in a non turbo were the brakes were soft all the way to the floor but still worked normal

Problems with brake effort with normal brake function are almost always booster related

I reckon I should be able to grab one locally.

I'll confirm it's stuffed first as I don't know enough about properly testing them, I am only assuming that air I felt is a problem.

I'd prefer to have it confirmed.

No air should escape AFAIK. But seen as they are under vacuum I will have to think about it a bit more.

The vacuum does disappear when you press the pedal a few times with the car off, But I think that is something to do with the 1-way valve and compressing the booster chamber. I'm not real sure to be honest lol. Will have to really think about it

EDIT: O.K, research done. the back (pedal side) of the booster should let atmospheric pressure into the booster when the pedal is pressed. So I think you said you are getting air on the other side of it so that might be your problem. Master side should always be vacuum, pedal side is vacuum until pedal pressed.

HowStuffWorks was awesome when I was 14, still awesome now that I'm 24 :) Click the link and it should help you understand it. It also shows how come you only get a few pedal presses before losing all brake boost assist

Edited by 89CAL

I read all the same stuff, hence taking it in.

Guy behind the counter was very helpful and said while he was not 100% it was definitely faulty, it should behave as you mentioned above (and as I can get one for $50 second hand easily enough to just swap it out).

I'll grab another and see how it goes.

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