Brake problems - is the servo shot?

[Rubce]

Hi Guys

Here is a puzzle for you to solve.

A few weeks back whilst manouvering the resto around the driveway a leak developed on the front wheel side of the PDWA valve resulting in a spray of fluid shooting out all over the nearside front wing. The dash warning light came on. I cleaned off all the fluid off ther paintwork and tightened up the offending pipe fitting. Topped up the front half ofthe reservoir.Brakes then functioned okay.

Came to reset the PDWA valve this morning and noticed that the fluid in the front half of the reservoir has dissappeared again. On my car that section of the reservoir is for the front brakes. No sign of any leaks anywhere. With the engine running the brake pedal is going to the floor with little resistance despite pumping it to get pressure up. All I hear is the sound of air passing.

Is the servo shot?

Regards

Bruce

[Moraystag]

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Bruce check the vacume pipe is not holed or perished and the connection isn't cracked. Probably the master cylinder as this is what went on mine with much the same symptoms apart from hissing

[Giles]

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I would not think the servo would allow the pedal to go to the floor? Sounds more like master cylinder if there is no sign of the fluid loss I assume ithas leakedinto the servo? See what others think.

[V Mad]

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Giles wrote:

I would not think the servo would allow the pedal to go to the floor? Sounds more like master cylinder if there is no sign of the fluid loss I assume ithas leakedinto the servo? See what others think.

I agree; this is a direct acting servo, so in the event of vacuum failure alll you should lose if the power assistance. There must be a fluid loss somewhere.

[flying farmer]

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If the fluid is leaking out of the front half it is unlikely it is getting into the servo, back half could well be.Is it still leaking out of the PDWA valve and running down inside the chassis leg?

Neil

[Rubce]

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Gents

Neil was right, the PDWA was still weeping from the large washer at the front end.

Think I will fit a replacement new one. Does anyone have experience of the brake bias valve that James Paddock sell. Is it a modern direct replacementof the PDWA as they are selling it under the same part no. 155071.

Regards

Bruce