Severe brake pedal travel after changing pads

[wetdogleader]

Hi, I have an 06 Vito 115 and have just changed the front and rear brake pads. I used genuine Merc pads and did the fronts first. After having changed the front pads the pedal has gone very soft and indeed if you keep your foot on it will travel to the floor. I have bled the brakes and it made no difference. I spoke to my local garage who said he had the same trouble with one and that if you continue to drive the vehicle the pedal will come back ( bit risky!). There is a fix for this that Mercs seem to keep closely guarded. Anyone know what it is please!

 

[panason1c]

Hi, I have an 06 Vito 115 and have just changed the front and rear brake pads. I used genuine Merc pads and did the fronts first. After having changed the front pads the pedal has gone very soft and indeed if you keep your foot on it will travel to the floor. I have bled the brakes and it made no difference. I spoke to my local garage who said he had the same trouble with one and that if you continue to drive the vehicle the pedal will come back ( bit risky!). There is a fix for this that Mercs seem to keep closely guarded. Anyone know what it is please!

Master cylinder gone Kaput.....Check out this thread..............
http://forums.mercedesclub.org.uk/showthread.php?p=231178#post231178

 

[amb67]

Yep, Panason1c is probably right.

When the caliper pistons are pushed back in to make room for the thicker pads the pistons seals can be pushed past the fluid inlet ports and this can cause the actuator piston seal lip to become damaged. The damage can be so minute that when you strip the MCyl down you can hardly notice it.

Do the brakes work at all, when you press on the brake pedal on all modern vans and cars the pedal will sink to the floor after a few seconds.

Does pumping the pedal with the engine running produce a hard pedal?

What you need to bear in mind is that new pads will produce a crap brake feel for around the first 500 miles. They need time to bed in.

 

[Ellsy Tanners]

You will have put the pin retaining spring for the rear pads in incorrectly.

ive done it myself on the vito.

It will be pushing the rear pads back againest the pistons and pushing them back in, thus making the pedal travel more to take up this travel everytime.

Check the rears!!!

I have just read the year of your van and its alot newer than the ones ive had problems with, however its stil a viable cause might be worth checking!

 

[wetdogleader]

Severe brake pedal travel after changing pads Reply to Thread

Thanks for the replies. I was unaware that the pedal can travel to the floor when held down on modern cars and vans. I have been driving it and the brakes seem OK as they only require light pressure anyway and the vehicle is manual (so not so reliant on brakes). The retaining clip might be a possibility but it wouls have to be the front ones as I checked the pedal after doing the fronts and the problem was there then before I did the rears. I'll persevere with it for a bit longer and see what happens after they have bedded in properly.......Thanks again for your replies

 

[oldcro]

(Quote from wetdogleader) and the vehicle is manual (so not so reliant on brakes). EeK! Please explain what you mean by NOT SO RELIANT ON BRAKES, as brakes are the most important items on any vehicle.

 

[panason1c]

on all modern vans and cars the pedal will sink to the floor after a few seconds.

I've not heard/been aware of that before, are you sure?

 

[oigle]

I've not heard/been aware of that before, are you sure?

Me too!!!!
I've never seen such a thing on any car with properly operating brakes. Would have to have a leaking cylinder somewhere for that to happen. New pads sure do need some miles to bed in, particularly on worn grooved discs. They will be soft for a while.