Do I Need to Bleed Hydraulic Shocks?
 

After having my 88’300TE sitting for a couple years it’s back on the road again and the reservoir for the hydraulic fluid on the rear shocks is empty.

The shocks were leaking prior to parking it and I plan to buy new ones, but as temporary solution if I refill the reservoir will the shocks come back up?

I seem to remember reading somewhere that they had to be bled like a brake line. I’d sincerely appreciate it if someone would enlighten me on this.

123's have a self bleeding SLS. I've heard from other 124 owners that it too is self bleeding. I believe it's the SLS on 126's that requires manual bleeding.

I had problem with my 92 300 TE making a clanking noise from the rear. Lots of trouble to diagnois. Turned out to be coming from the rear shocks.

We bleed the system and noise was gone.

So I would say yes they can be bled. See link below for my problem with shocks.
http://www.peachparts.com/shopforum/tech-help/143256-clanking-noise-rear-300te-whats-source.html?highlight=hydraulic

They all can be bled manually (actually compressing the suspension while opening a bleed valve), but in my 123 I bounced on the rear bumper a bunch of times and it burped the air out through the return line into the reservoir. Any air I missed came out while driving.

If all you did was fill the reservoir and drive, I would imagine it would take quite a while to get enough bounces that would completely self bleed the system.

That is what I had done. Empied the reservoir to clean it and to remove rear shocks to design and make new bump stops, since the old ones were completely gone.