The guru's that have responded are spot on with their test requests. You need to isolate to the subsystem that is causing the problem. Then test individual related components.
That said, these old 6 bangers can be notorious to restart after a good run. Alot has to do with how well the intake is heated or the lack there of and condition of all the sub systems.
A tried and true procedure is thus:
While cranking, slowly fully depress the throttle then slowly lift up. What you are doing is varying the fuel/air mixture while cranking to find the happy spot. I have to use this procedure on my 49 216 regularly and it works 100% of the time.
Do NOT apply choke once it's warmed up. You'll flood it and that causes a whole new set pf starting issues.....
Likes been said, theres an art to owning/operating/wrenching these old manually fabulous machines of yesterday. You are the CPU with them.
