Is there anyway to test the injection pump to ensure it is working properly? I recently purchase a used 2001 and the guy said he does not trust oil injection so he was running mixed gas. I would like to run unmixed .

 

The oil injections on them are pretty much bullet proof. Just about every 90 2 stroke has the same motor and oil injection system. IIs everything still there? If so I would fill the oil tank up, take the oil line off to bleed the air out and run it with mix for about a tank full. Then just use the oil injection from there. If the exhaust stops smoking then there is a problem. You can run the premix and the oil injection for a bit and see if the oil tank level goes down. Chances are that there is nothing wrong with the oil injection but he just ran it dry so there is air in the lines.