A reader asks: We are thinking of running AMSOIL Dominator Synthetic 10W-30 Racing Oil in our Briggs Local 206 kart racing engines. The question is about the break-in process. Should we run AMSOIL Break-in Oil, a dino oil or can we use synthetic oil right off the bat?
Our Answer: Why not break-in the engine with the Dominator 10W-30? While the AMSOIL Break-in Oil would be OK for your Briggs & Stratton kart engines, it is designed more so for large displacement automotive engines. Your Briggs kart engines use only splash lubrication and require an engine oil with maximum anti-foaming resistance. Dominator 10W-30 is a much better option for those considerations.
But will the synthetic Dominator Racing Oil allow the rings to seat during the break-in process? Absolutely, 100% yes. Synthetic oil will allow rings to seat and leave you with an engine with great compression, minimum oil consumption and maximum engine protection. The notion of piston rings not seating properly when broken in with a synthetic oil is an old wives tale from the disco era.
AMSOIL Dominator 10W-30 Racing Oil delivers a number of benefits for air-cooled, splash-lubed engines such as your Briggs Local 206. These benefits include minimized friction, maximum wear control, robust foaming suppression and cooler engine temperatures.
So yes, definitely break-in your engine with AMSOIL Dominator 10W-30 Racing oil and stay with it for maximum engine life and output.
Note that this question came from a Canadian resident. Kart racers located in the United States can use Briggs/AMSOIL Synthetic 4T Racing Oil in 4-stroke Briggs engines. 4T Racing Oil was developed through a joint partnership between Briggs & Stratton and AMSOIL for their 4-stroke kart racing engines. AMSOIL does not export 4T Racing Oil to Canada and it doesn’t sound like they will anytime soon. The break-in advice above applies to karts racers using 4T Racing Oil as well. We have covered how AMSOIL Dominator 10W-30 is an outstanding substitute for Briggs 4T (and perhaps even an upgrade) in Briggs & Stratton kart racing engines.
Update January, 2018- Oildepot.ca now sells Briggs & Stratton Synthetic 4T Racing Oil in Canada.