Need a new thermostat for an Isuzu industrial or marine engine? This is a direct replacement for part numbers 5137700221 and 5137700101. It's compatible with a bunch of Isuzu engine models including the 4BD1, 4BG1, 2AA1, 3AA1, 3AD1, 2AB1, 3AE1, 3AF1, and 3AG1. It's also listed as fitting the Hitachi EX50UR excavator (which likely uses one of those Isuzu engines). This is a brand new aftermarket part designed to match the original specifications, helping to regulate your engine's coolant temperature properly for efficient operation and to prevent overheating. Before you buy, it's super important to verify that this part number matches the one you're replacing or is correct for your specific engine model. A correct thermostat is a small part that plays a big role in engine health. Keep your equipment running cool and reliable.
