Hello,
First off would like to say Thank you in advance for any input.

We have a CGP 30 that will not start and here is what we have done so far:

We ran it with the tank shut off and it ran out of propane and would never restart;

I removed the line to the regulator and it has good flow to and from the regulator , when we removed the line from the vaporizer to the carb it was getting propane up to the carberator but it seemed to be putting an excess of propane into the carb. The only way I can get it to run is pull the top of the carb off and crank it over and eventually it will run for 15-30 seconds before it dies. With the top of the carb off it does spray propane out of the carb steadily with the cover off. I removed the air filter thinking it was creating a rich state with no success.

We replaced the diaphragm in the vaporizer about 3 months ago

Im really good with gasoline style carbs but this propane system has me a bit confused. Could the carb be plugged some how?
Thank again in advance
Jake