I agree with Chuck.  Inspect and replace the components as needed... not "just because".  While all sorts of things can happen, the adjusters have two main wear modes: rounding off of the square drive end, and corrosion of the adjuster threads preventing them from turning.  Once adjusted, not much happens to/with the adjusters.

See https://www.minimania.com/part/17H7620/Classic-Mini-Cooper-Brake-Adjuster-Kit-For-The-Rear-Brakes

It doesn't hurt to take your parts out to see what kind of shape they are in.

Are these to be replaced, along with the springs when renewing the shoes. Is there anything that should be replace at that time?

This is one of those things that will be obvious to you once you start "tightening" the adjuster.  

See the link below for a picture of the adjuster.  The square faceted front conical end pushes the shoes out against the inside of the drum.  Each time you turn the adjuster you will feel it push the shoes out and then pop forward a little bit so the shoes are resting on one of the adjuster's flats. 

Again... once you do this the first time you'll know the feeling.

As far as tightening your car's drums more, refer to the information I put in my first post above.

Can you describe what the adjuster feels like when it "clicks into place"? I feel I can improve a little more on my '68's
rear wheel adjustment as well.

An '85 should have discs on the front which removes the grief of adjusting the front drums.

As advised, tighten the rear brakes and think about a brake fluid change.

The rear brakes will be drums and for what you describe, start by adjusting the rear brakes.  You will need a brake wrench to avoid rounding the corners of the adjuster.

The brake adjusters are 4-sided wedges advanced by turning them 1/4 turn at a time using the special 4-point brake wrench.  Don't be tempted to use an open end wrench or adjustable wrench.  The adjuster heads are just too easy to round off.

With the parking brake off and one rear wheel elevated, turn the adjuster in 1/4 turn steps (you will feel the adjuster "click" into place).  You want to tighten the adjusters up until the wheel can just be turned by hand.  You should hear a bit of brake drag and the wheel should stop spinning at about one revolution.  If the wheel can be rotated and it spins much more than one revolution... they need to be tightened more.

If your front brakes are also drums, they will also benefit from adjustment.  I will let others describe the best method to adjust front brakes.  I have only done it twice on a Mini.

Obviously buy a manual.  Haynes is a good starting point.  However, it never hurts to have multiple manuals to reference against one another.

Hello all,

 

I'm new to mini's but not new to turning wrenches.  I recently picked up a 1985 mini, in a bit of rough shape, but it does run and drive.  I'm trying to sort the brakes at the moment so i can enjoy it a bit before tearing into the rust repair.

My current issue is, the brake pedal goes halfway to the floor before I get any braking response.  From my experience, it acts as though the brake pushrod needs adjusting, but i can't seem to find any adjustment for it.  Is there adjustment available hidden under the dash where i'm not seeing it?  Is this just normal for a mini?  Or should I go about on the assumption the master cylinder is no good and needs replacement?

Thanks!

Pete