Replaced the 40 year old Pierburg mechanical pump with a Vaico brand. They claim to be a German aftermarket manufacturer, but I heard that they're made in China.

Anyhow, I'm getting oil seepage out the weep hole. Brand new pump. Do you guys have any experience with them? Is it possible for the fuel pump to somehow suck out oil if they're bad? Is is worth asking for a replacement or just chalking up to "lesson learned" and forking over $200 for a Pierburg? Or should I do away with the mechanical setup altogether and install an electric pump?

What's the best course of action for long term reliability? I have a Weber conversion in the mail as well, so I'd like to address the pump and forget about it.