The kill switch often is the problem. If that doesn't work read the link below.
Engine Trouble - Engine wont start? TROUBLESHOOTING GUIDE
If your Happy Time engine isnt starting then work your way through this guide to identify and fix the problem. Still no hope? then just ask... With many thanks to BoltsMissing who compiled this great troubleshooting guide. Thanks to Lordoflightaz too for a few tips :) Firstly start off by...
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