OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Tecumseh / Kirby Engines greenfeild 12.30 techmesh ohv125

Spark plug gap seems to be 0.030", like most modern mower engines:
http://www.gardenresources.co.uk/content/garden_machinery/manuals/husqwm246_hwen1998_5321635-78.pdf

Carburetor adjustment is a bit trickier to find - Tecumseh engines are not all that common in Australia. Here is one person's opinion on it:
http://simpletractors.com/Club2/topic.asp?ARCHIVE=true&TOPIC_ID=49829

The carburetor adjustment isn't likely to be at all complicated, and the advice given on that site is very similar to Briggs and Stratton procedure, so it is probably about right.