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Brake booster failing?

vc commodore

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Yes,Repco used to sell exchange Boosters back in the VN Day but they were pricey,not sure if they still do but some of the smaller independants have taken it over i was told,Rare Spares?


Not sure who sells them new these days...I do know ABS brakes in Adelaide reco them at a cost of about $400 for a double diaphram commodore booster.... :)
 

Turd Ferguson

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Back to throw some more fuel on the fire on this one.

Car hasnt been getting driven as ive been doing some work on it ( Including new IAC and 02 sensors)
Still has a lousy idle when braking.

I noticed today that The idle got PROGRESSIVELY worse as I pushed the pedal, especially if I put it hard to the floor the idle goes noticeable worse.
If I really listen I think I can hear a slight air leak when pushing the pedal, it must be quite minor but just enough.

Will scope out a local wrecker to see if I can get one, if not theres a place or two in Adelaide that reco them.
 
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vc commodore

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The symptoms you describe do sound like a failing booster....Maybe speak to a brake specialist and see what they say...

I have a double diaphram booster here to suit VB to VR (I think VR) that has no leaks and works well, if you require.
 

MikeC

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Back to throw some more fuel on the fire on this one.

Car hasnt been getting driven as ive been doing some work on it ( Including new IAC and 02 sensors)
Still has a lousy idle when braking.

I noticed today that The idle got PROGRESSIVELY worse as I pushed the pedal, especially if I put it hard to the floor the idle goes noticeable worse.
If I really listen I think I can hear a slight air leak when pushing the pedal, it must be quite minor but just enough.

Will scope out a local wrecker to see if I can get one, if not theres a place or two in Adelaide that reco them.
Maybe take off the booster hose and plug it- then see if it still happens. At least this test will confirm if the problem's in the booster.
 

Turd Ferguson

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Don't believe I mentioned it earlier but definite evidence the old master cylinder was leaking out the back, paint had bubbled down the front of the booster where brake fluid had been running.
 

Turd Ferguson

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Update: Booster from a VP at the wreckers has fixed it.

The old one

PXL_20210529_014553132.jpg
 

Skylarking

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And the prize goes to vc commodore for his post #2 :p
 

vc commodore

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And the prize goes to vc commodore for his post #2 :p

What's my prize :p

Seriously, that booster looks like crap...Also glad the OP found the problem and posted up the end result....
 

Skylarking

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What's my prize :p

Seriously, that booster looks like crap...Also glad the OP found the problem and posted up the end result....
Its a gold plated “I was right” card. You’ll get a visit from the forum fairies at night time and they’ll leave your prize under your pillow :p

Jokes aside, good call.

But I’ve seen worse paint blistering on one of my cars and in that case both brakes and engine worked well. So it’d be interesting to see the condition of @Turd Ferguson’s booster internal‘s (diaphragms and seals) to get a better handle on what actually caused the major air leak impacting the engine... Yeah, I know these units are not rebuildable by the layperson but curious what the inside looks like :rolleyes:
 

vc commodore

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Its a gold plated “I was right” card. You’ll get a visit from the forum fairies at night time and they’ll leave your prize under your pillow :p

Jokes aside, good call.

But I’ve seen worse paint blistering on one of my cars and in that case both brakes and engine worked well. So it’d be interesting to see the condition of @Turd Ferguson’s booster internal‘s (diaphragms and seals) to get a better handle on what actually caused the major air leak impacting the engine... Yeah, I know these units are not rebuildable by the layperson but curious what the inside looks like :rolleyes:

I would suspect there would be brake fluid inside, which has caused the seals to fail...Or the beginning of the failing, hence the air escaping noise described along with the engine miss.... :)
 
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