Engine stall on startup 337B NA?

[Jhogan0101]

Yesterday i landed and got fuel (OAT 90F, Field 1000’MSL)
Plane was sitting for about 30 mins.
I got in to fire up using primer knob instead of fuel pump.
Primer seems to work better for starts imo.
I primed 4 times (front) started up, got to about 2000 rpms then slowly stalled out.
It was similar to when you shut down engines using mixture.
This happened 3 times total and then started like normal and i was able to fly for 3 hours fine.
Sumped tanks, no water, hangared plane.
Any ideas why this would happen?

[Learjetter]

Sounds like vapor lock from heat in line from throttle body to flow divider & maybe in line to fuel pump. Engine would rev on primer fuel and stall when pump pushed vapor to nozzles.

One technique: full throttle, idle/cutoff mixture and run aux pump for about 20-30 seconds to push cooler fuel thru lines to pump. With pump on, Hit starter and crack mixture 1 inch open or so until she lights off. Then quickly turn pump off, and open mixture full rich while pulling throttle to idle. Takes three hands or practice to time it all correctly.

[general]

Standard vapor lock scenario if you would have hit the Boost pump probably in low the engine would have smoothed out