I read your post how do you know that it's not getting propane into mixer first will it start with a small amount of starting fluid if so than l would think you are correct.l would than check vacuum the emco converter and fuel lock need vacuum to pull fuel into the mixer also make sure the vacuum line from the fuel lock is on the carb also l believe it uses a ca55carb make sure the plunger is moving when you are cranking and not stuck this would stop vacuum and cause no propane to draw. I would than check compression to moter to make sure you are dealing with a good moter also check propane hose low pressure from converter to mixter might have small hole in it the emco runs on 1/2 of gas pressure small leak from hose would not allow to start.if won't start on starting fluid you have a spark problem hope l was of help
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