Truck should still run iif someone replaced with ca100 carb check to make sure no hole in carb diafram and when cranking it is moving up. Could be stuck. Also put vacuum gauge on motet and see what the vacuum is cranking. Make sure they put all gaskets from govern to carb.if not drawing propane has to be vacuum problem if you replaced most parts.

It has the ca100 set up. It will run with starting fluid. The compression is good. I think someone put the wrong set up. My parts department says it's wrong.

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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