Brake Pedal Creep, Very Low Braking Efficency.

[BobLeeSwagger]

Hi, i have an S reg Hilux single cab and the brake pedal goes a long way before there is any braking and when there is some, it isn't much. Also, if you pump the brake pedal it builds up pressure so the pedal becomes quite firm but then still creeps back to the floor. If you do this whilst driving (I've only been testing it down the farm track) there is none or very little braking.

I bled it all, No change. I've just fitted a master cylinder repair kit and bled it all again and still no change.

When you pump the pedal with the engine off, and press it, it doesn't creep. The only thing affected by the engine is the servo but i have no idea how that works.

Is anyone able to shed some light on the subject?

Thanks, Tom.

[4x4Steve]

when i was a young un i was told you can check your servo is working with the engine off, pump the brake until it goes hard, this is basicly emptying the vacume from the servo, then with your foot still on the hard pedal start the engine

if the servo and the pump work properly then the pedal will drop a little,

try that first,

[BobLeeSwagger]

Ah right, thank you. I have done that and it drops a lot. I'll have a look around all the flexible pipes tomorrow to see if they are swelling up under pressure.

[4x4Steve]

Ah right, thank you. I have done that and it drops a lot. I'll have a look around all the flexible pipes tomorrow to see if they are swelling up under pressure.

it proves that the vacume pump is working, so it leaves 2 possible faults

either the seals are damaged/faulty or the vacume chamber has a leak, the chamber is the big round thing under the master cylinder

[4x4Steve]

just a thought, it could just need !Removed! good bleed, ????

[BobLeeSwagger]

I fitted new pistons and seals in the master cylinder, and then bled the whole thing. I even carried on giving them a few more pumps once i got to the clean brake fluid just to make sure. Kept the resevoir full to the max mark the whole time. This may be a daft question, but there are only the 4 bleed nipples on the calipers to do aren't there? There are no more lurking around anywhere else?

It could be a leak in the vacuum chamber then. Thanks very much.

[4x4Steve]

I fitted new pistons and seals in the master cylinder, and then bled the whole thing. I even carried on giving them a few more pumps once i got to the clean brake fluid just to make sure. Kept the resevoir full to the max mark the whole time. This may be a daft question, but there are only the 4 bleed nipples on the calipers to do aren't there? There are no more lurking around anywhere else?

It could be a leak in the vacuum chamber then. Thanks very much.

in the back of my mind is a thought that there is a bleed nipple in the brake compensator,

its the think at the back, with a lever from the axle to it

[BobLeeSwagger]

I did wonder if that might have something to do with that. I never thought of there being a bleed nipple on it. I'll have a look at that.

[BobLeeSwagger]

Just wondering, is there a certain order in which i should be bleeding the brakes? I'm currently working from a Haynes manual for a Ford Sierra (it's all i had) and it says to start at the left front, then right front, right back, then left back.

You were right there is a bleed nipple on the load compensator... Or there was until i gave it a slight twist with a spanner and it sheared straight off.

[4x4Steve]

Just wondering, is there a certain order in which i should be bleeding the brakes? I'm currently working from a Haynes manual for a Ford Sierra (it's all i had) and it says to start at the left front, then right front, right back, then left back.

You were right there is a bleed nipple on the load compensator... Or there was until i gave it a slight twist with a spanner and it sheared straight off.

good to know ther is one there

and i was always told furthest one away from the master cylinder,

i can look in my manual, its at work so will have a look tomorow

[Jackwout]

I’m having the same drama 

I’ve replaced everything apart from brake booster and vacuum pump. I have no bpv on my car for some reason..

my brakes lock up all fours on first push then second brake push less brakes third even less while getting a very hard pedal while brake are (Mod edit), when you pull up to and intersection while holding foot on brake it slowly sinks all the way to the floor.

any held would be great full