Starter motors and dual-purpose starter-generators fall under 851140. Alternators — which generate AC current for vehicle electrical systems — are classified under 851150 as generators for internal combustion engines. The key distinction is function: starting the engine (851140) versus generating power once the engine is running (851150).

Yes — the heading covers electrical ignition and starting equipment for both spark-ignition and compression-ignition internal combustion engines regardless of the vehicle type, so marine outboard and inboard engine ignition parts, as well as piston-engine aircraft ignition components, are classified here. The end-use sector does not change the heading.