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hi again, my 318 '81 has some issues with uneven brakes in the front. when i brake semi hard it has a tendency to pull to the left. is this common and does anyone have an idea what could be the problem? i havent yet disassembled anything as i dont quite know where to start and why

You can´t adjust the brake bias from side to side. Only answer is that the hydraulics are not working properly. The first (and cheap and easy) step to do would be to remove all old brake fluids from the car completely. It needs to be drained. Put in new fluids and vent the brakes on all 4 wheels. Then in theory it should brake even. If it still is not braking even, the issue can be with the brake pads, or in extreme cases the brake caliper itself.

But i would definatly try to replace the old fluids first and vent the brakes.

My 2 cents:

1. Beware not to be misled by road conditions. Roads are shaped convex to get rid of rain water. But if you tried in different situations and roads, you may be right and your brakes may apply different forces left and right.
2. I don't expect miracles from changing fluid. In most cases the brake calipers do not move freely anymore because of build up of rust and dirt in the chambers behind the calipers, something you will never be able to get out by bleeding the brake system.

My advice, especially if you have no idea when the calipers have been rebuilt or if it has been ages already: remove the calipers for a full rebuild. Replace rings, dust caps, rubber o-rings between caliper halfs, clean the chambers out completely and make sure the pistons are refitted without a singe trace of rust or an uneven surface and use (Ate) brake grease for refitting all parts.

Then apply fresh brake fluid, not a can you've had in your shed for ages, and fresh brake pads. Re bleed after a few 100 kms. You will guaranteed be amazed by the difference an afternoon of tooling will make.