Vacuum pump oil leak

[bobimihi]

Hello!
I have already doubled disassemble vacuum pump from the engine. This is necessary because there is an oil leak. A common problem with this model Saab. I brush, buy a new rubber seal and install vacuum pump to engine. I did that at the end of July. Oil leaks stopped. Last week I noticed that the oil flows back from the same place.
Has anyone faced this problem? What further I need to do to stop the oil leak?
I am grateful for every answer, an idea and a proposal to eliminate this annoying problem.
Thanks in advance!
Bobi

[Peter Robson]

When top bolt is removed, the seal between cover and pump body leaks. Remove and reseal with high temp silicone. Use new seal between pump and engine. Have repaired 5+.