Brakes?

[andyjwhit]

Evening all, havent posted in a while as all has been good with the car. Went out today and the brake padel seemed a bit spongy but stragely the travel was about half usual and then pedal went hard/almost solid but without any increase in stopping power, most strange. Can anyone shed any light on this? Thanks Andy

 

[spyderman]

When was the brake fluid last changed?

 

[andyjwhit]

Hi Spyderman, last done eighteen months ago at OPC, so due next service in Aug

 

[Chris_in_the_UK]

Sounds like a case of brake piston knock back?

 

[spyderman]

Good call on a piston issue - time for a refurb.

 

[JuliusF]

Ah yes, piston broke, know that feeling! I think if it was just brake fluid it would be sponginess only.

Trip to the dealers for this one I think (easy job for an indie).

Best.

 

[Richard_Hamilton]

Another possibility is the brake servo. Early 996s had a problem with the bellows seal, which allowed water into the servo, causing it to rust badly inside. You would have thought that it would have manifested itself by now, but would be worth checking. If you want the full TSB, drop me an email.

 

[andyjwhit]

Hi Guys, thanks for the feedback, had never heard of knockback? Does this mean the brake calipers have springs in behing the pistons and that one of them has broken?

If its the servo guess its easy for OPC to do without breaking the bank?

Thx Andy

 

[Chris_in_the_UK]

Hi Andy

Knockback is either vibration or unevenly worn disc (including rear face corrosion) which pushes the piston further in than it normally sits. When you hit the pedal it takes a bit of travel before you feel any braking force (which is where the 'soft' pedal feel comes from) followed by a normal solid feel at the second press as the piston is where it should be after the first press.

 

[andyjwhit]

Hi Chris, thanks for the clarification, rear discs were replaced two years ago due to corrosion on inside face.

Richard pls can you let me have your email address, thanks

 

[Levasseur]

If servo is fine it could be something further up the line, like the vacuum/tandem pump or a hole in the hose connecting to the pump.

 

[Richard_Hamilton]

ORIGINAL: Levasseur

If servo is fine it could be something further up the line, like the vacuum/tandem pump or a hole in the hose connecting to the pump.

996s don't have the vacuum (tandem) pump like a 997.

 

[Richard_Hamilton]

ORIGINAL: andyjwhit

Hi Chris, thanks for the clarification, rear discs were replaced two years ago due to corrosion on inside face.

Richard pls can you let me have your email address, thanks

Just click the email link under my avatar.