So after about 50+ hours of working on my shop project, my L2850 GST suddenly is extremely hard to start. It had been running great and always started with ease up to this point. I pulled the fuel line off the lift pump, and it seems to be pumping ok, not a lot of volume or pressure, but it is pumping. So is my main pump shot? How do I check the main pump? Is there a rebuild kit out there for the main pump?