OTTO Sh4503B 6Uz1 Japan Nikko Genuine Electric Starter Motor 12V 24V 1811004320 181100-4320 1-81100432-0 For Isuzu Engineered for harsh mining conditions, this Nikko genuine motor delivers instant, stable ignition for SH4503B excavators. Unlike low-quality replacements, it resists wear and voltage fluctuations, slashing downtime and maintenance costs, and keeping your mining operations running nonstop.