I had an issue when I had to remove the PS unit. Got air trapped and had a heck of a time getting it purged. It belched oil on every turn of the wheel. In all the times of working on a PS issue, never had one quite like it.

Yours sounds like it may be just worn out, or possibly a small hole or lose fitting allowing air into the system, and pushing the oil out when pressure builds???

There was a post on a E-Body ps unit that had a small rust hole in one of the plates and leaked oil all over the place. Like one said, how can rust materialize in a unit completely filled with oil.

Let us know what you find out.



Sorry I could not be of help on this one.