Servo or Brake Master Cylinder BMC?

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LDV8
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Servo or Brake Master Cylinder BMC?

Post by LDV8 »

Hi guys,
Recently had front binding brakes. Replaced front brake hoses and calipers but still the same. The vehicle binds intermittantly.

I'm trying to work out if it's the Brake Master Cylinder or Servo.

I also recently noticed that on a cold start up I get a hissing from inside the cab from the servo (intermittant). I generally have to pump the brakes for this to stop (hissing not all the time).

Is there a safe way to check if it's the servo without disconnecting the Servo and driving the vehicle (to eliminate the Servo)?
Also had replaced last year, new brake pads, shoes, discs, drums, rear brake cylinders and fitting kit.

Any ideas?

Thanks,
Richard


Cheers KC

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ChrisJC
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Post by ChrisJC »

I would go for disconnecting the servo myself, and use the 'fear assisted' brakes that result!

Chris.
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LDV8
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Post by LDV8 »

considered the white knuckle ride but concerned about pulling the steering column and box through bulkhead!

Richard
Cheers KC

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Ian Anderson
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Post by Ian Anderson »

Disconnect the Vacuum from the servo - this should be reasonably easy.

Make sure you have an 8 0r 10 mm bolt to hand with which to block the "suck" going to the inlet manifold. (Push bolt into vacuum pipe and jubilee clamp in place)

Take for a test drive - after about 3rd application of brakes you should have no vacuum assistance left.
If the brakes then continue to bind I would susopect the problem lies elsewhere (Sticky piston or caliper)

IAn
Owner of an "On the Road" GT40 Replica by DAX powered by 3.9Hotwre Efi, worked over by DJ Motors. EFi Working but still does some kangaroo at low revs (Damn the speed limits) In to paint shop 18/03/08.

LDV8
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Post by LDV8 »

My only concern for that test is that I have an LDV Convoy Ex ambulance with a RV8 and I'm guessing that with what I carry on board I reckon it must weigh in at about 2.5-3T. Now if I need to brake sharpish then will I brake in time?

I might end up driving around for a good few miles before it happens if at all on a shortish journey! Intermittant faults don't you just love them!
Cheers KC

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Post by unstable load »

LDV8,
Your braking will be a bit less effective due to the lack of power assistance, but it should well be compensated with an increase in adrenaline :twisted: :twisted:
Cheers,
John

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Re: Servo or Brake Master Cylinder BMC?

Post by stevieturbo »

LDV8 wrote:Hi guys,
Recently had front binding brakes. Replaced front brake hoses and calipers but still the same. The vehicle binds intermittantly.

I'm trying to work out if it's the Brake Master Cylinder or Servo.

I also recently noticed that on a cold start up I get a hissing from inside the cab from the servo (intermittant). I generally have to pump the brakes for this to stop (hissing not all the time).

Is there a safe way to check if it's the servo without disconnecting the Servo and driving the vehicle (to eliminate the Servo)?
Also had replaced last year, new brake pads, shoes, discs, drums, rear brake cylinders and fitting kit.

Any ideas?

Thanks,
Richard
Suck on the vac pipe going to the servo and see if it is leaking. That should be a bit safer than driving lol

Or attach a vacuum gauge to the line and block either side of the gauge in turn.
The servo is sealed should maintain a decent amount of vacuum for a while.
And see if when the other side is blocked, if engine vacuum reading stays the same

Any other symptoms ? High idle ( ie air leak )
9.85 @ 144.75mph
202mph standing mile
http://www.youtube.com/watch?v=XgWRCDtiTQ0

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