i have been experiencing diesel run on and the brakes get stiff!
this has happend off and on..i read that this could be the vacum box.
but could this mean the booster too.i am not the most experinced yet with this car cause it has had no problems.
:P thanks fellas!!!! 1983 turbo diesel

You are on the right track. Both the brake booster and engine shutoff are vacuum actuated and a leak will cause problems with both. It could be the pump or it could be simply a matter of a loose fitting or cracked line. Invest in a mityvac tool to troubleshoot the problem if a visual inspection does not yield any results.