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Mechanic Martyn
Mechanic Martyn, Australia Car Mechanic
Category: Australia Car
Satisfied Customers: 1002
Experience:  Advanced trade certificate in Automotive engineering
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RANGE ROVER SPORT 3.6 V8 DIESEL: 2010 RR 3.6 V8 sportBrake

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2010 RR 3.6 V8 sport
Brake pedal on first press after vehicle standing over night goes to the floor , release second press full pedal. Start engine with pressure on brake pedal it slowly goes to floor within 30 seconds
I would put that down to a failed master cylinder - one of the primary seals has failed inside the master cylinder - not much you can do except replace the master cylinder.
Mechanic Martyn
Customer: replied 3 years ago.

Customer: replied 3 years ago.


Ok - thank you for that extra bit of information.
The problem is still likely to lie with the master cylinder though.
It's possible that the pushrod to master cylinder clearance is wrong. If there is insufficient clearance between the two it can cause the master cylinder to not refil properly on the return stroke.
It would be worth getting the brake people to check that.
Has there been any other work done on the system?
Mechanic Martyn
Customer: replied 3 years ago.

A Landrover agent has checked system out and tells me they are ok . this does not seem right four the brake pedal to act in this way , Vehicle done 41000. Hope you can help
Thanks Eric.

Eric you are right it shouldn't act this way - I spent 12 years on rover - I am quite sure your master cylinder is internally bypassing - there is nothing else on your vehicle that will give that symptom.
Take it back to the Land Rover agent and point out that it is still doing it and they need to check it further.
They might try and point to the ABS system but that will not do this symptom.
If you like I am quite prepared to opt out of this question and throw it open to other experts to see if anyone has any other ideas.
Mechanic Martyn
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