Quote:
Originally Posted by kerry
That doesn't make sense to me. If crankcase blow-by is forcing it's way past the vacuum pump diaphragm there wouldn't be any vacuum in the system causing the brake booster to fail and making most people stop driving and fix the pump to get their brakes back.
|
He means the shut off diaphragm fails, crankcase blow-by is forcing it's way into the vacuum system.
Even a small rip or puncture will pass a lot of oil.
With the engine running, shutdown:
* Vacuum is applied to the failed shut off diaphragm.
* Crankcase blow-by is forcing it's way into the vacuum system.
* All of the MB vacuum pumps that do not have a second dedicated vent/output hose; air vacuumed from the system is vented into the crankcase, increasing crankcase atmospheric pressure = making the issue worse.