Your vacuum pump can have a break in the rubber diaphragm allowing oil to be sucked into the manifold.

There could be a rip in the leather diaphragm on the governor on the rear of the IP.

You can also have a bad head gasket.

Also your air filter is an oil bath type....this can also be dirty...

You may also need a valve adjustment.

My friend had a w115, it was an awesome car but it had a lot more headaches then a w123. After doing a lot of work on it....the head gasket blew....rebuilding the engine isn't easy....I personally would say a w115 is a around town on the weekend driver....won't last being a commuter...

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