Brake issues... no fluid when bleeding

[Lippy]

I've bled brakes many times on many different cars. I haven't bled the brakes on my E30 yet, but wanted to do it today as the brakes have been feeling soft.
I'm using the Schwaben pressure bleeder (very similar to the Motive bleeder).
Starting from the passenger rear, I started bleeding. Opened the screw... nothing. Removed the screw completely.... nothing.

Same thing happened for every wheel except the drivers front.

I'm not sure whats going on. Bad Master Cylinder?

The fluid was pretty dirty and the brake reservoir looks a little gunky too. It really needs a good flush... frustrated I can't do it.
I pulled as much fluid from the reservoir as I could and replaced it with fresh, but not nearly what needs to be done.

I test drove the car after and it seems about the same as prior to bleeding, perhaps slightly better.

[Jordan]

Very likely the ABS hydraulic unit is coked up with sludge, schmutz and schmoo blocking flow and all but certainly completely inhibbiting ABS function.

Crack the outlet fittings loose at the ABS unit and see if they bleed out there. Outlets are the 3 top fittings. If they do bleed out the issue on your car is down stream in the lines of calipers. If they don't leak go ahead and tighten them, then crack the bottom input fittings loose and see if they leak. If you have flow at the inlets... you need a ABS pump.

Here is an idea of what you can expect to find inside:

https://mtechniqueauto.com/lies-within

[AWDBOB]

I haven't had much luck pressure bleeding E30s. Not sure the science behind that, but it almost never works, for me.

But every E30 I've bled recently, I've had to pull the bleed screws out and clean the fluid passages to get fluid to pass, so that would be a good place to start.

Try some good ole 2 person brake bleeding, but also pull bleed screws to check for debris/clean.

[Lippy]

I did pull the bleed screws completely out and still no fluid. I replaced the back two with new ones, I would have replaced the front as well, but the bleed screws in the front were longer than the back, so it didn't look like the ones I bought would work.
I'm going to try to get a brush attachment for my Dremel or something like that and try to clean the caliper bleed screw passages like AWDBOB suggested.

I hope its not the ABS pump. There is no way I'll find a working one of those. Even if I did, it would probably cost more than the car.

[Lippy]

Forgot to mention, I'll also try to crack the fittings on the ABS pump to check that as well. Thanks Jordan.

[peytonracer4]

I had to bleed a reman caliper on my e46 recently and spent a couple hours trying to figure out why no fluid would come from the bleeder screw on the caliper. Was going to return it but in a last ditch effort, the person pressing on the brake pedal gave a lot of pressure and "something" came out and popped the cherry. After that, everything was normal. Maybe try the two person method and give it a little more pedal pressure than you normally would.

[hopeful]

Forgot to mention, I'll also try to crack the fittings on the ABS pump to check that as well. Thanks Jordan.

I don't know if that would be a good idea in your case, as you may end up introducing air into the system which will only add to your difficulties. I'd definetly just do the two people method as suggested by another member.

[E30 Wagen]

I haven't had much luck pressure bleeding E30s. Not sure the science behind that, but it almost never works, for me.

But every E30 I've bled recently, I've had to pull the bleed screws out and clean the fluid passages to get fluid to pass, so that would be a good place to start.

Try some good ole 2 person brake bleeding, but also pull bleed screws to check for debris/clean.

Same here, pressure bleeder failed to do the job for me twice, had to get somebody to help. Probably one of the two jobs I most hate doing along with burping the cooling system.

[Jordan]

I hope its not the ABS pump. There is no way I'll find a working one of those. Even if I did, it would probably cost more than the car.

Not that big of a deal, and its possible and likely that will be what you ultimately find out. I rebuild these pumps, and I sell a lot of them to E30 owners. There are 7 different non-M E30 pump variants starting from $949 w/ core exchange.