Bleeding brakes or find a leak

Need some help with a technical problem - ask away and let's see if we can all help.

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911hillclimber
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Re: Bleeding brakes or find a leak

Post by 911hillclimber »

I still think you should change the master when all else is adjusted.
The pedal should hit the brakes in much the same spot every time, the position should feel familiar every time.
73T 911 Coupe, road/hillclimber 3.2L
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Nine One One
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Re: Bleeding brakes or find a leak

Post by Nine One One »

If the master cylinder is knackered, it does not matter how many times you bleed the brakes, air will be getting in via the master cylinder.
For that small cost to replace it, you then have everything renewed. At the moment you will just be chasing your tail, using endless brake fluid, because air is still getting in the system. The Master Cylinder is the heart of the brake system, if that is not working correctly how can you expect the other bits to do so?
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Re: Bleeding brakes or find a leak

Post by mycar »

If you're ditching your master cylinder, take the opportunity and go dual circuit.
911hillclimber
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Re: Bleeding brakes or find a leak

Post by 911hillclimber »

Very sound advice indeed.
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
neilbardsley
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Re: Bleeding brakes or find a leak

Post by neilbardsley »

I've already bought a new master cylinder at a princely cost of £50!
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911hillclimber
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Re: Bleeding brakes or find a leak

Post by 911hillclimber »

Tandem cylinder is a good mod, independent feeds to Front and Rear, but a stock single system should work as well under normal driving.
Will you fit the new one now?
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
neilbardsley
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Re: Bleeding brakes or find a leak

Post by neilbardsley »

911hillclimber wrote:Tandem cylinder is a good mod, independent feeds to Front and Rear, but a stock single system should work as well under normal driving.
Will you fit the new one now?
I will try some weekend. Maybe not this. How many hours for a numpty like me? 1-2 hours to change then another hour to bleed?
“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
911hillclimber
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Re: Bleeding brakes or find a leak

Post by 911hillclimber »

Yes, spot on esp if the wife does her job right!
73T 911 Coupe, road/hillclimber 3.2L
Lola t 492 / 3.2 hillclimb racer
Boxster 987 Gen II 2.9
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hot66
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Re: Bleeding brakes or find a leak

Post by hot66 »

neilbardsley wrote:
911hillclimber wrote:Tandem cylinder is a good mod, independent feeds to Front and Rear, but a stock single system should work as well under normal driving.
Will you fit the new one now?
I will try some weekend. Maybe not this. How many hours for a numpty like me? 1-2 hours to change then another hour to bleed?
If you’ve not got one, buy or borrow a proper brake fitting spanner as the fittings are easy to round off using a standard spanner
James

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1993 964 C2
2010 987 Spyder

1963 Honda C100 Supercub

Its not how fast you go, but how you go fast ;)
neilbardsley
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Re: Bleeding brakes or find a leak

Post by neilbardsley »

hot66 wrote:
neilbardsley wrote:
911hillclimber wrote:Tandem cylinder is a good mod, independent feeds to Front and Rear, but a stock single system should work as well under normal driving.
Will you fit the new one now?
I will try some weekend. Maybe not this. How many hours for a numpty like me? 1-2 hours to change then another hour to bleed?
If you’ve not got one, buy or borrow a proper brake fitting spanner as the fittings are easy to round off using a standard spanner
I wasn't aware that a brake fitting spanner existed. Which nuts/bolts are you talking about? On the hoses I've been using 17mm and 11mm. On the bleed screws 7mm?
“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
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hot66
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Re: Bleeding brakes or find a leak

Post by hot66 »

its nothing particularly fancy, but does a much better job and gives you a better chance of not rounding the fittings ... assume 356 fittings are standard size ?

this kind of thing

https://www.halfords.com/workshop-tools ... re-spanner
James

1973 911 2.4S
1993 964 C2
2010 987 Spyder

1963 Honda C100 Supercub

Its not how fast you go, but how you go fast ;)
neilbardsley
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Re: Bleeding brakes or find a leak

Post by neilbardsley »

Changed the master cylinder today. Took for a short test drive. Bite further down the pedal but this may be because the pedal needs adjusting to the new cylinder?

I'm not sure if the problem is resolved a longer drive is needed

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“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
Nine One One
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Re: Bleeding brakes or find a leak

Post by Nine One One »

You adjust the throw on the rod, but also are all the shoes adjusted correctly?
neilbardsley
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Re: Bleeding brakes or find a leak

Post by neilbardsley »

I adjusted them a while ago but worth checking. I normally adjust to the point just before I can hear any contact

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“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
neilbardsley
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Joined: Mon Apr 16, 2012 4:31 pm

Re: Bleeding brakes or find a leak

Post by neilbardsley »

Victory!!

I now have a firm, high bite. I adjusted the pushrod but completely lost the firmness. Then I decided to check again and saw the 2nd nipple on the front wheels!!! Numpty of the year award but lots of lessons learnt.


Now the car needs a service as its backfiring as I take my foot off the gas as it drops from the main to idle circuit.

Sent from my HTC One M9 using Tapatalk
“A REMINDER. I would be grateful if those members who have borrowed bits from me in emergencies (e.g starter motor, oil cooler, etc) would return them and/or contact me”. – Chris Turner RIP
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