Improved starting on Yanmar 1GM10

[ianwoods]

After two years of poor starting I had the Injector serviced by diesel factor who informed me of its incorrect spray pattern. Cost £15. Starting and running are less smokey. Took a few cold starts to find the new "best position" for the throttle lever.
Injector never removed for 10 years. Is there a recommended service interval?

 

[Spuddy]

Go on - what's the new best position. Could help me out after the overhaul.