Bobcat 7753 won't crank

[Firescooby]

Bobcat 7753 was running fine a couple of days ago. Today it started to crank, but wouldn't stay running. Opened hatch and squeezed primer bulb just in case. It only took one pump to firm up, still wouldn't fire. Opened hatch again and noticed primer bulb is "squeezed" and won't release. Ideas? Thanks

 

[flyerdan]

The primer bulb has a check valve in it, so if it won't expand again once it's been squeezed, that means that it's fighting a vacuum. I would suspect an obstruction in the fuel line or a tank vent problem.
If you take off the fuel cap and hear a giant whoosh of inrushing air, that's the vent problem, if not the next logical test would be at the fuel pickup tube. Some of them had a screen or mesh sock that can crud up.