I have a 10 year old Sears mower with a Briggs and Stratton 16HP OHV engine. Last week it started blowing tons of white smoke and stopped running.

After some research I decided to change the head gasket and generally clean up the engine. Changed the gasket - no problem, cleaned the bypass valve, put new plug and all back together.

Engine started right up - ran for about 2 minutes then stopped. Would not restart.
Pulled valve cover and verified valves/pushrods were cycling the valves - no bent rods.

Checked spark - fine
Checked compression - fine
Checked fuel flow after the filter - fine

If I spray starter fluid into the carb - it still won't start - get a couple pops and backfire but no run.

What do I check on the carb? This unit has a solenoid on the bottom - I assume this shuts off fuel flow.

Help!!

Yes the solenoid on the bottom is a fuel shutoff.
Use carb cleaner instead of starting fluid.