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Brake booster failing?

Skylarking

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So by depressing the brake pedal, whilst the car is running and a rough idle appears along with air noise, what would this indicate?
If the owner doesn’t know, it would indicate they should go to a mechanic and have it looked at :p

Jokes aside, as I said, if one holds their foot on the brake pedal and air noise continues, something is stuffed within the booster so it needs investigation/replacing... The fact the engine gets too much unmetered air just adds another indicator to the mix but we already knew that :p

It’s just a shame boosters are sealed units as they are dumb as door knob devices that should be able to be rebuilt.
 
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vc commodore

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Jokes aside, as I said, if one holds their foot on the brake pedal and air noise continues, something is stuffed within the booster so it needs investigation/replacing... The fact the engine gets too much unmetered air just adds another indicator to the mix but we already knew that :p

It’s just a shame boosters are sealed units as they are dumb as door knob devices that should be able to be rebuilt.

Did we know that air escaping, with a rough idle means the booster is buggered? It seems by the responses, the rough idle part of the issue has been overlooked by many....:)

Boosters can be rebuilt....From memory it was going to set me back about $400ish to have the booster rebuilt for my VC.....Didn't go down that path, because I found a 2nd hand unit cheaper which fixed my problem....
 

DavesSV6Tonner

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I found it was cheaper and less hassle to buy a new Master Vac for our VS from our local Holden Dealer.
That probably won't be an option these days.
 

Fachoo

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Calm down mate.

If you can hear air when pushing the brake pedal you can't be certain it is not the seal failing on the input shaft. Common enough and something I have personally experienced. Certainly not something to simply discount at any rate like you suggest.
No sweat mate I wasn’t saying any seals were failing or discounting anything
I clearly stated you can get atmospheric air noise with just pedal movement, similar to a hand pump motion producing squish noises. I certainly wasn:t saying it was air loss from booster diaphragm fail as that would be obvious if it happened to anyone.

If you read the 1st OP post he clearly states that ....
The car stops alright in terms of brake performance but I really have to go beyond half way on the brake pedal before anything starts happpening.
With the car turned off the pedal pumps up fine and goes firm, but with engine running it is very spongey. I get a bit of air noise when depressing brake pedal with engine running. I also noticed my idle can go a little rough depending on my braking so Im thinking my booster is on the way out.
So according to OP brake performance is good, spongy pedal and a bit of air/rough idle when braking, car is old VN so idle probably not perfect for age in the tune, autos, especially when drawing vacuum for brakes or any other part needing vacuum, once driving you wouldn:t notice anything.

He did booster test and ok and still working properly for good brakes.... so it:s not a booster fail....... that leaves the spongy pedal feel, well proper bleeding and different master cylinder conversion change points to be his issue which can produce a spongy feel even when the brakes stop properly and have no major leaks....can also be the booster vacuum check valve poorly working.

So lets not simply discount those items at any rate which you haven:t suggested
 

vc commodore

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No sweat mate I wasn’t saying any seals were failing or discounting anything
I clearly stated you can get atmospheric air noise with just pedal movement, similar to a hand pump motion producing squish noises. I certainly wasn:t saying it was air loss from booster diaphragm fail as that would be obvious if it happened to anyone.

If you read the 1st OP post he clearly states that ....

So according to OP brake performance is good, spongy pedal and a bit of air/rough idle when braking, car is old VN so idle probably not perfect for age in the tune, autos, especially when drawing vacuum for brakes or any other part needing vacuum, once driving you wouldn:t notice anything.

He did booster test and ok and still working properly for good brakes.... so it:s not a booster fail....... that leaves the spongy pedal feel, well proper bleeding and different master cylinder conversion change points to be his issue which can produce a spongy feel even when the brakes stop properly and have no major leaks....can also be the booster vacuum check valve poorly working.

So lets not simply discount those items at any rate which you haven:t suggested


I don't recall seeing where the OP did a booster test, even after re-reading the whole thread....Perhaps you could point this out for us to see....

You also say you're not discounting a booster fail, then after quoting the OP's original message, you say it's not a booster fail....Doesn't add upto me....
 

Fachoo

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I don't recall seeing where the OP did a booster test, even after re-reading the whole thread....Perhaps you could point this out for us to see....
Why don:t you PM Turd Ferguson Being the OP I am sure he can indulge your questions considering he has the answers.
You also say you're not discounting a booster fail, then after quoting the OP's original message, you say it's not a booster fail....Doesn't add upto me....
Same as Above ^ ^ ^ ^ ^
 

vc commodore

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Why don:t you PM Turd Ferguson Being the OP I am sure he can indulge your questions considering he has the answers.

Same as Above ^ ^ ^ ^ ^

You're the one stating a booster test was done, not the op....Just re-read your previous post and you'll see where you made that statement....So it's upto you to post the quote up, not the op
 

vc commodore

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Calm down mate
Nobody has to do or say anything just because you want it so.
Simply if you:re that desperate to know anything ask @Turd Ferguson who started this thread

But your the one making statements stating the booster has been tested then saying it hasn't....then you pass the buck just like now....

Seriously it's not hard for you to point out where it has been stated the booster has been tested
 

HarryHoudini

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Boosters can be rebuilt....From memory it was going to set me back about $400ish to have the booster rebuilt for my VC.....Didn't go down that path, because I found a 2nd hand unit cheaper which fixed my problem....

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?
 
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