Author Topic: brake pedal not returning fully when hot  (Read 461 times)

w116john

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brake pedal not returning fully when hot
« on: 28 May 2018, 09:04 AM »
hi all

driving the car today and got it nice and hot and i found that the brake pedal was not returning fully and there was a noise from the rear until i lifted the pedal with my foot. the pedal feels fine brakes are firm not hard. i have had suspicion of a sticky caliper on the rear right for some time. the pedal is not returning the final 2 inches maybe.

any advice appreciated

john

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Re: brake pedal not returning fully when hot
« Reply #1 on: 28 May 2018, 10:15 AM »
It's possible you have a clogged brake hose or two. If they are older hoses, there is a high chance that the rubber inside is deteriorating and restricting flow. I had an identical experience with a clutch cylinder--it would engage fine, but I would have to lift the pedal back with my foot. When I replaced the hose, I pushed out a long cylinder of rubber. Also, with the rear brakes of another Mercedes--despite replacing parts and adjusting, the rear brakes kept dragging--it was once again deteriorated hoses that were allowing pressure one way, but not allowing the fluid to flow backward.

Old, clogged brake hoses will give the same symptoms as dragging calipers.
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w116john

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Re: brake pedal not returning fully when hot
« Reply #2 on: 28 May 2018, 01:39 PM »
 hi

i will have to get it checked out soon, strange its not an issue when cold, i will replace the fluid and pipes and see how it goes.

thanks
john
« Last Edit: 29 May 2018, 02:11 AM by w116john »

robparker

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Re: brake pedal not returning fully when hot
« Reply #3 on: 28 May 2018, 01:57 PM »
Just to throw out a simple idea too.. on my 202 I had the same problem, and after replacing everything it turned out to be the actual pivot the pedal moves on was old and seized. Pedal removed and new bush £2 from mercedes, like new again. Don't know if this can translate to the 116
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w116john

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Re: brake pedal not returning fully when hot
« Reply #4 on: 29 May 2018, 02:17 AM »

hi

thats what i'm hoping, it is something small, the brakes were not the next project i had planned,  i have some rust in the engine bay i want to sort out.

thanks all the best
john


w116john

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Re: brake pedal not returning fully when hot
« Reply #5 on: 24 June 2019, 03:53 PM »
hi all

just to close this case,  it was the front brake hoses that caused the problem, as soon as i replaced them i had a normal pedal.  i have replaced most of the brake parts except the front calipers which are fine, i am really glad to get this job done gives a bit more confidence on the road

thanks for the advice