merc.190e brakes locking on

[N.kench]

Help! my brakes will lock on sometimes on the rear other times on the front.
ive checked the calipers they are free, ive changed the master cylinder,
discionnected the relays to the ABS still lock on ive disconnected the servo
still lock on this usually happens after about 2 to three miles when one can feel the brakes binding with that acrid burning smell I am at a loss to get the ABS
checked out garage want £150 need a solution Help!

 

[television]

Hello and welcome, I would change the 4 flexi hoses, it is known that the inside can collapse blocking the fluid from returning, the only other thing is the one way valve on the servo, or a servo fault

 

[N.kench]

Mercedes 190 brakes locking

Hi malcom. thank you so much for responding so fast! Ive replaced the front flexible pipes and drove it with servo vacuum disconnected and the brakes still locked. where is the one way valve situated?! when brakes are partially locked i released the pressure from the bleed valve on the wheel and it then spins freely but locks up again once brake is pressed. My garage says it must be the ABS...:I appreciate your help.

 

[television]

I have been thinking and the servo would not cause it, even with a leak in the vacuum part. the car does not have BAS, so no sensor, and this only leaves the ABS pump, there are quite a few being broken, 201's that is

 

[N.kench]

mercedes 190e brakes locking

hi malcolme drove the car 7 miles from start up without touching the brake then
all of a sudden the front brakes started binding. went swimming left car for 45 minutes then drove home without any problem .

 

[wireman]

Given that you have changed the most likely culprits this is an unusual fault, it could be the ABS since that's all there is left to change and it is older than the 10 year life its manufacturer suggests. However it may be the pedal is not fully returning to its rest position and holding the master cylinder piston(s) just past the snifter holes thus creating a hydraulic lock which as the fluid expands (due to warming) increases the system pressure untill the brakes begin to bind and get hot, then expansion goes skywards. Some vehicles have adjustment on the push rod for this.
Check this before you shell out loads of cash on changing the ABS pump unit.

If the car has had its regular brake fluid changes neglected, go and get all the bits that have not been changed yet, because they will all be suffering from degraded flourinated rubber components and more faults will occur, some of which are much less safe than binding and slowing progress.

Was there any blackness in the fluid reservoir when you started out fixing it?

 

[N.kench]

shall have a look at brake pedal and see if it can be adjusted .thanks very much.