Help!

I have a POULAN Lawn Mower that has a Briggs 450 series Engine. It is two weeks old. It starts but will not maintain a throttle. The longer I prime it the longer it runs but or no more than 15 seconds though. What is the problem?

When it goes to shut down and doesn't "chug" smoke at the very end then it would be a lack of fuel in carb. That's why "priming" keeps it running.

If its 2 weeks old then it should be under warranty.

Since its so new the needle and seat valve should be fine along with fuel pump. The only thing I can think here is for some reason the carbs "float" is stuck in the down position and hung up in carb bowl not allowing fuel to enter carb.

Tap on carb with a screw driver handle and see if that makes a diff on the float position..

A pinched gas line could have the same effect here also..

I would suggest more here but the warranty needs to stay intact...