was curious if anyone has a defective (under the cowling) oil reservoir for a pro xs laying around. my cap worked its way loose and when tightening it will go tight, and then pop loose. i believe the threads may be stripped as i see no crack at the neck of the tank. mercury will not sell just the cap, only the tank assembly with the cap. my back up plan would be to find a 9/16" expanding plug (like a live well plug). mechanic told me as long as it holds in the oil it will work, but im sure mercury frowns upon it.