First, which of the four or five Surpass 120's do you have. They all plumb differently. Do you have a pump? Is there a regulator on the carb. A few more answers, and We can give you the right plumbing setup.

A small black pump and a small black regulator cover on the carb is a Surpass III W/ Pump. An aluminum pump with no regulator on the carb is the Surpass I. The aluminum pump with aluminum regulator is the Surpass II. The I and IIplumb about the same. The non pumped ones IE the 120E are like any other engine, two or four stroke. The Surpass III is a two line from the tank to pump, one vent and one supply. None of the pump engines us a line from the muffler to the tank, and all need a vented to atmosphere tank.

Don