I recently just put 20 inch eight hangers on a softail 1993 Fatboy and emptied all the fluid out of the brake master cylinder because I had to replace the cable because I had to extend it. I installed the cable and filled it up with fluid and I’m trying to bleed the brakes and there’s no fluid coming out. Any help would be appreciated.

 

What DOT type fluid are you using?

Has the master cylinder ever been rebuilt?

 

It reads like you have a 1993 Fatboy..basically a softail frame.
The master brake cylinder for the front wheel was emptied during a cable replacement...a longer cable replacement was installed.

You are reporting that you are trying to bleed the brakes and there’s no fluid coming out.

Assuming system was functional before + you are using the same fluid as replacement + there are no leaks....
I believe that from factory that model is DOT-5 but who knows what somebody has done after a few decades.

Keep in mind that it will take about 50 SLOW pulls and SLOW releases of front brake lever to move the fluid when that master cylinder is empty.
It can sometimes take an additional 12 pulls over the original 50 to get fluid movement and a fully functional stiff lever.

*Reason: The amount of fluid movement is actually rather small with each lever pull so it can take many pulls (+50) when conducting a manual changeout.

 

Hook up a Mighty Vac to the bleeder screw, open bleeder and keep pumping till brake fluid starts to flow.

 

Use a syringe connected to the caliper bleed nipple ( use a short piece of bleed tube)

Pull the plunger to create vacuum, then crack the bleed nipple. Close and repeat till you “ suck” the fluid through.

 

Use the suggestion vacuum pump. Replace the little blender cup with a Masion Jar. Drill two holes in the Mason seal ring . One hose to the bottom. Other just thru. (refer to the small plastic one if that doesn't make since)

Keep the vacuum low or you will pull air into master under cup seals.

Note, it's best to bleed a empty master first.

There is a very good chance if your master is old, pumping it and letting it botton drives the cup seal into corrosion at the bottom. The master may need to be rebuilt with a sleeve and piston kit if it's available.

 

I agree on the vacuum pump method. Could also try reverse bleeding from caliper up to the master.
If nothing is coming out perhaps you have an obstruction. (Dumb question but you are remembering to open the bleeder at the caliper correct?)

 

I use a bleeder that hooks up to my air compressor they are cheep at Harbor Freight works good. As some said after all of them years maybe its time to rebuild won't hurt.

 

I went through this on my front brake several weeks ago, and it takes a lot of time to get every bit of air out. I did a little write up of what I did in the thread titled DOT 5 or something like that.
The reservoir really wants to hold some air and even the line itself due to stiction. Tapping on the line, fittings and reservoir gets the air to release and come up through the reservoir.
Vacuum did help on the caliper, but it still took quite a while to work every bit of air out. Vacuum did not get it out of the top reservoir for me. Keep at it OP'r. Just takes time

 

Look for a video on reverse bleeding. Then follow that. Master cylinders don't last forever. New parts on old bikes help a lot. I had a similar problem a few years back.