Lt155 fuel pump not pulling fuel from tank.

[SimpleLawnBoy]

I have a Lt155 lawn mower where the fuel pump is not pumping the gas from the tank to carb. The previous owner claims he put a new pump on it, and I also bought a new one just to make sure. And still no luck.
I set up a gravity feed tank to the engine and the engine ran perfect so I know it's the pump. I am at a lost. It's a Kohler 13hp engine.

 

[Born2Mow]

The pump is vacuum operated. Ideas...

• Replace the hose that takes the vacuum from the engine to the pump with std automotive fuel hose rated SAE J30.
• Check that the pump output and input aren't reversed.
• Check the fuel lines for blockages or restrictions. Fuel line should be replaced every 5 years or so.

 

[Hammermechanicman]

Pull the fuel pickup out of the tank and check for grass plugging it.