Vacuum pump issues maybe?
 

Morning all
Recently my brake pedal would get very hard when I'm going down hill coming to a stop.
Ive read in several threads here that there is a valve of some sort on the vacuum line leading from the pump to the master cylinder.I just cant find one(valve).I know for sure its a vacuum issue but would it be all related to the pump itself? Would a vacuum check on the line itself give me a false reading,thinking it would be the pump and not the so called valve if there such a valve or visa versa?
I have attached several pictures for you to tell me where this valve would be.
Thank you,.
Dan:confused:
1983 300SD

Anyone???:confused:

There's a check valve in the vacuum pump itself. If I were you, I'd hook up a vacuum gauge to the lines, run them into the car and monitor the vacuum on the brake booster line for a while.

Will do
Thank you

I have a couple of threads on here about the hard brakes on my 77 300d
Turns out the pads had worn down enough that the spring that holds them in place was contacting both sides of the caliper, stopping it from squeezing the pads enough to provide braking power. I'm not the only one who experienced this. Don't know if same problem applies to an SD.