Got a real problem on my hands which is the reason I registered.
I really hope someone can help me cuz I'm out of ideas for now.
K, I got an Audi 80 B3 '89 1.8S PM. No ABS, drum brakes in the rear.
The brake fluid was dark as night, and the braking distance terrible. So I figured I'm gonna flush it all and bleed it. It's been ages since anyone even looked at it. Said and done.
After the bleed though, I still got a soft pedal if not even softer LoL! o.O
I tried bleeding the system a couple of times, thinking I was doing it wrong and some air was still left. I used 3 litres of fluid to be exact. Still no improvement.
I then bought a new master cylinder as the old one started to leak cuz I pushed it too far -.- But it was very old anyway so good riddance
Also bought two new drum brake cylinders as one of the old ones was leaking a bit. Then I disassembled, cleaned and re-assembled the drum brakes.
I tried bleeding it the "one person" way I found on the net which is put a bottle with some brake fluid on the floor and pump the pedal.
Also tried hanging the bottle upside down and thus filling the hose with fluid, then opening the valve and pumping a few times.
Even tried with someone pumping the brake while I open/closed the valve!
So I'm pretty sure no air is present in the system.
I also checked the brake proportion valve (brake force regulator) and I think it does it's job. I let someone pump the brake for me while I was rotating the wheel and moving the lever of said valve.
When I applied pressure like the spring would when the back of the car is loaded, the wheel stopped earlier as opposed to relieved pressure where it would take quite some brake pressure to activate the rear brakes.
The valve moves 0.5/1mm when I manually tried it.
When I push the brake pedal it goes slowly to about half way until it stops. I feel the rear drum brake shoes expanding as I push. As if they need to travel some distance before touching the drum o.O
I checked the pads and drum surfaces and they're still OK. Also very little clearance between the two.
When I deactivate the rear brakes via the brake proportion valve so no or very little fluid is moving to the rear, I get a harder pedal.
Also when I apply the parking brake I get a much stiffer pedal. So obviously it's something related to the drum brakes?
I was thinking of buying some new brake shoes, but I'm not sure what that would do really?
Any advice on this? I'm really desperate since I'm trying for a few days to make the brakes work
I linked two pics of the brakes just in case.
I appreciate any help! thanX!