Re: bought a replacement engine and it wont start.
Don't give up. We'll get you running.
Spark plug color has nothing to do with if it is working or not. Brown is actually what you want to see but that comes later. Did it spark when you tried the test I described above?
For test purposes you can plug the idle screw hole with a piece of tape. Is your carburetor one of the earlier, NT style or the trouble prone CNS type?
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