Hi!
Does anyone have an idea where the problem might be? So the rear drum brake on driver side has really bad braking power compared to the passenger side. I've so far changed everything on the brake except drum and springs ( Still in delivery), bleeded rear brakes multible times, tried sanding the drum, reassembled the brake a few times. Still not fixed.

 

Have you replaced the wheel cylinder on that corner? Years ago I got bit by a semi-seized wheel cylinder. Attempted to diagnose low brake pedal concern and replaced pretty much everything in the system but the wheel cylinder. Exhausted, I finally did and when you know it it returned halfway. Stupid, cheap parts can sometimes cause the biggest headaches.

 

Yes, I did replace it. The old one was in a bad shape but didn't help. Maybe I should try bleeding more. There was some random air bubbles last time bleeding it. I did bleed close to 1.5 litres of fluid through the rear lines but maybe there is more air still?

 

That would be the next place I'd go, yes. Make sure the line is tight too and not reintroducing air.

 

Adjust it up until you can JUST BARELY still get the drum on over it. If the drum has a lip, replace it before trying to make it work. Otherwise you'll have to adjust it up with the drum on, which requires sticking a tool through the backing plate, which you might not even have a slot to do that through, and even if you do, it's a major PITA.

"When in doubt, swap it out".

 

If you really want to know get a brake pressure gauge and see what you're getting at that wheel. When you say 1 wheel has bad braking power how are you measuring/gauging that?