In the Bentley manual it mentions using a special BMW tool to depress the brake pedal slightly to prevent fluid loss when changing the brake hoses. Has anyone tried this? How much is "slightly"?

 

i think that might be just to prevent sucking in air when you brake the hoses loose. it's a messy ordeal. brake fluid is very corrosive.

my special tool is my torque wrench. i slide the seat up to hold the wrench between the brake pedal and the seat. not much pressure but enough to hold the wrench there.

this also reminds me to torque my wheels before i drive off. yes, i have forgotten in the past.

 

I believe pushing the pedal down a little bit pushes the master cylinder piston beyond the feed holes from the reservoir, preventing the fluid from just draining out through the opened brake line. It also creates a small suction on the line, much like putting your finger over the end of a straw filled with liquid.

 

It does seem to help. I had my rig slip and fluid bagen dripping out prety fast. Once I jammed the pedal again it slowed almost to a stop.

 

While I cannot confirm this on the MINI it is the case on the SRT4. The description is pretty accurate.