Other Deleted

Chrisjb330 said:

Changed all calipers and hoses today, bled them all individually then all in sequence after. Good pedal with the engine off.

However with the engine running and hard pressure on the pedal it goes slowly to the floor. Brakes fine, holds at the lights fine etc.

I've read this is normal, can anyone confirm?

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Have you driven it? has the pulling to one side been cured?

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Brake pedal creep to the floor is not a standard feature of any good brake system - it's a symptom of leaking mastercylinder seals in both brake circuits.
Its often tolerable though because its only significant when you press the brake pedal lightly & hold for a long time (ie not normal braking). If you hit the pedal hard - as in an emergency, the higher pressure often causes the seals to seal properly until you release the pedal.

Diesel creep is the effect mentioned in the other forum post where if you put your foot on the brake pedal it moves down a fair way (BUT NOT to the floor) immediately after you start the engine when its been off for a while AND you have leaking Servo Non Return Valve. It's caused by the the servo brake assistance only slowly building up as the disel engine vacuum pump slowly builds up vacuum IF it's leaked away. The vacuum pump can often take many seconds to build up to max. vacuum / assistance.
The same effect is also present on some petrol engines nowadays - as some also have vacuum pumps.
Older petrol engined cars don't noticably have the problem because the vacuum level is built up very fast to a lower level than a vac pump (as soon as the engine is running at idle there will be good vacuum)

Chrisjb330 said:

Still pulling to the left but that disc has worn in more than the rest, will give it a week to bed the other side in.

Trying to confirm if I need a new master cylinder or not now.

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If one side has bedded in quicker then you may still have an issue, how many mile have you done?

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Pawl said:

Thanks for sharing that info.
"Brake grease" is normally only designed for reducing friction between metal parts not in contact with brake fluid - eg caliper slide pins, brake shows to drum brake backplates etc
You've obviously found a better grease that is brake fluid compatible.
At the least the piston seal grease supplier also acknowledges the infamous "Red rubber grease is not a suitable piston seal lubricant – it’s not a low friction lubricant and is too thick to remain long between seal and piston" - but they miss the major issue that it's a mineral fluid based grease & therefore should never be used near brake fluid related components.

Good luck finding the cause of the pull.

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Ive been using red rubber grease for over 30 years, rebuilding callipers, no issues at all. Ask your local MOT shop to do a brake test on your car. It will highlight how much the braking system is out of balance.


Here is a comprehensive list of RRG properties:

• Fully compatible with natural and synthetic rubbers
• Compatible with brake fluids and some hydraulic oils.
• Rust inhibitor (protects from oxidation and rust).
• RRG is water resistant.
• Hight temperarure. The grease can be used in applications with temperatures up to 210-230F. It will not melt and will not contaminate brake pads.
• Petrol resistant. Although it will get contaminated in contact with gasoline, but still it will protect rubber parts from it.
• High chemical and structural(mechanical) stability.
• High resistance against water washing (will stay on after a rain, or car wash).
• Has high wear protecting quality.

http://www.redrubbergrease.com/tips-how-to-brake-caliper-failure-repair-with-rebuild-kit.html

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I forgot about the brake tester.... I mentioned it because I just had it done on the wifes car...

What you do depends on how deep are your pockets. If youve replaced the discs, pads and callipers, New thing would be a worn suspension or steering component. What condition are the springs or shocks ? Im just in the process of replacing the bushes in my lads Defender, as the car is all over the road. Found two knackered bushes on the N/S suspension arm already, and thats just the first thing I started on.

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THe steering wheel position wont make it pull to the left on braking. Have you got a set of pry bars, to check the bushes, like the MOT tester does ?

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Did you change the master cylinder in the end...

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https://www.ebay.co.uk/itm/174644380875?hash=item28a99dc4cb:g:8dMAAOSwbgNgL8aj

This set would help. Nice if it was a bit cheaper. Tests the brake line pressure in the line, via the calliper bleeders.

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