Honda Outboards BF40A/BF50A Service Manual, Page 330Get this manual
BF40A-BF50A NozzlesJets
Check the main jet, main nozzle and jet nozzle for debris
or damageReplace if necessary
SE (Starter Enrichment) THERMAL VALVE
1) Check the valve piston and needle for wear or
[2J NEEDLE
[1] VALVE PISTON
scratchesReplace as assembly, if necessary
2) Measure the resistance between the terminals