Bach TR-500 Student Bb-Trompete

I was excited to get this trumpet as a backup to my trusty Shew. Except for the adjustable 3rd valve ring it look pretty much like a Strad. The bell is a little smaller and tighter that the Strad though. Overall it is a nice looking horn. When the valves started to hesitate after a half hour or so of playing I thought that maybe it was lapping compound so I cleaned the trumpet thoroughly in warm soapy water twice and rinsed well. I relubed everything with Hetman slide grease and Al Cass oil. After another hour of playing I noticed more hesitation and more black goo in the valves. After the 5th cleaning it is still oozing whatever the contaminant is and therefore the horn is unusable. Bach should be ashamed of this horn!