I've been studying the debate regarding pre-mix with or without a functioning OMP. My question is, can you actually see some oil flow in the flexible lines from the OMP to the carb? I'm wondering if mine is working. I'm going to test it with the lines off, but they are a little hard to access. The lines seem translucent enough that you could see some oil move through them.

 

You should be able to see oil working their way through them unless they're covered in dirt.

 

Normally you can see the oil as it creeps up to the carb. It only pumps a very small amount actually. The FSM has details for testing it out. Its good to check it once a year to make sure its still working as designed. Very little can go wrong except for leaking at the pump mount on the front cover.