"Paul... Sounds like you'r
"Paul... Sounds like you're only obtaining power on four cylinders. If you've got good compression and spark that will jump a 7/16 gap (with the s/plugs out) on all cylinders, the problem would have to be fuel related. YOu say that the engine took two months to be fixed and that the carbs were rebuilt two months before that... means that the carbs have been sitting for four (4) months. They could foul in that length of time.
Remove the large black plastic carburetor face plate and start the engine. With the engine running, stick two fingers in the top left carburetor throat which will act like a choke, then repeat the process with the right top throat, center left throat etc etc. The engine will have a tendency to slow down on the carbs that are okay... but will increase in rpms when you do the carb that's fouled. Clean that one. Keep me informed.
Curious.... you had the p/pack rebuilt or simply replaced?
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