Thread: P38 Total Brake Failure!

Range Rover Solutions Sell them

I am sure you would have read the many posts about this issue already, if not just google it and you will find the threads on AULRO

Originally Posted by 65s2a

I bought an unregistered P38 a couple of months ago (I've always liked the look of the MKII Range Rover), worked my way through a list of "issues" and got it registered a week ago. Even though it is now registered, the issues list still seems to be quite extensive?
As I was leaving the car park at work last night, the new item of: TOTAL BRAKE FAILURE got added to the list **** but no harm done.
After a tow truck home, research on line is currently favouring the need for Brake Modulator Repair Kit (BMR Kit ~ $100) with stainless steel rather than plastic washer item. Does anyone know where these are available from please?
Mine is 95 4.6 HSE, Brake fluid reservoir is full, accumulator pump was fine but now runs continuously, I'm wondering due to the failure of the plastic item?
I still have to confirm that this is my issue but even if it isn't, from what I have read the plastic thingy should be replaced...I'm thinking that Rover designers may have let them selves down a bit on this item.

I may be able to help you, I have a spare accumulator and also a modulator that has the kit fitted. I don,t mind you using these to find the problem as I,m in Brisbane (ferny hills), so call me if you need assistance.

Ken 0400 429283

Originally Posted by 65s2a

I bought an unregistered P38 a couple of months ago (I've always liked the look of the MKII Range Rover), worked my way through a list of "issues" and got it registered a week ago. Even though it is now registered, the issues list still seems to be quite extensive?
As I was leaving the car park at work last night, the new item of: TOTAL BRAKE FAILURE got added to the list **** but no harm done.
After a tow truck home, research on line is currently favouring the need for Brake Modulator Repair Kit (BMR Kit ~ $100) with stainless steel rather than plastic washer item. Does anyone know where these are available from please?
Mine is 95 4.6 HSE, Brake fluid reservoir is full, accumulator pump was fine but now runs continuously, I'm wondering due to the failure of the plastic item?
I still have to confirm that this is my issue but even if it isn't, from what I have read the plastic thingy should be replaced...I'm thinking that Rover designers may have let them selves down a bit on this item.

Before you do anything else disconnect the supply line from the brake fluid reservoir to the ABS motor and check if brake fluid runs freely out of it. If it doesn't then the you need to clean out the coarse filter that is inside the reservoir and that should fix your brake problem. If the filter isn't blocked then you can move on to the other usual suspects.

Hi and thanks for the help and offers of support. I plan to delve further into it this weekend. Yesterday I checked on another P38 that was wrecking, not running but still together, where brake pedal went most of the way to the floor and felt like a traditional hydraulic brake pedal which is what I would have expected normal behavior to be. Mine travels about two to three inches with only light spring resistance where it bottoms out to a rock solid stop. There is still four inches of potential travel before the pedal would hit the floor. Since I am in Brisbane, I will take up the offer of local help.
Since I'm new to the P38 it will be good to meet local enthusiasts. Thanks Les

OK, so it was the plastic piece on the master cylinder piston that was broken. When it breaks, it somehow allows the piston to come out of the bore and drop such that it won't go into the bore and no brakes...pedal stops halfway down. Also, the accumulator pump runs continuously, circulating fluid through the brake master assembly. I tested to see that there was fluid supply to the pump yes. I fed the pump from an external fluid source and the pump pumped this into the reservoir so I knew the pump was pumping.
I replaced the plastic washer with a stainles steel one, reassembled the master cylinder, bled the brakes and all is well except...the brake light stays on when ever the ignition switch is on.
I checked the switch with a multimeter, the switch operates when the plunger is mooved. I can manually move the switch throughout its travel and switch the ignition on with the switch open or closed and brake lights always come on.
Does the P38 have other things that intentionally turn the brake light on apart from the brake pedal switch?

Brake light problem was adjustment of the brake light switch mount (bent it slightly) All good now. Thanks Les