MK Brake Master Cylinder problem

[Robo]

How is it booster makes rear brakes work but not front, can't bet he right problem.
Think a common problem with those old MK was a small disc falling off the brake booster assemble internally.
symptom very long soft peddle with obvious less brake affect. Gen manual describes this affect, experienced this twice on a MQ and MK.
Service the front end.
Extra good chance calliper piston seals are swollen and causing pistons to stick, not to mention full of rubbish and possible corrosion. these all happen with an ageing vehicle , not to worry.
Another cause is because the rear haven't been working properly for a while the front have been working overtime and could be glazed up.
again this requires attention, recon machining is a waste of time they are so cheap to replace with new ones these days. For the age of vehicle, it'a good chance their under size anyway.

And those old rubber brake lines will be adding to spongy peddle feel also. whether you think so or not.
new rubber after market copied from original at local brake specialist should be a reasonable price, and Teflon lines are an upgrade very worth while they don't bulge and as a result give a much firmer peddle, a little dearer but recon worth it and especially for towing are worth the extra few $, Teflon around $300+ for all 6.
You really do feel the upgrade with Teflon lines.
Fix em right and they might just save your life.
Cheers.

[trublubiker]

You misunderstood, it was a faulty master cylinder, not the booster.

As you are probably aware it is a twin system, and the piston that pumps to the front brakes wasn't working, so no front brakes.

Anyway mate, job done, problem fixed. I've now got good brakes.

[Robo]

Sorry, my mistake.
that's what happens speed reading, glancing over.
So forget the first two lines.
the rest still stands.
Maintance/repair tip for brakes anyway.
Cheers mate.