Cummins Generator Error Code 118: How to Fix It

Q: Can I run the generator with low coolant pressure?

No, running with low coolant pressure can cause overheating and severe engine damage. Address the issue immediately.

Q: What coolant should I use?

Use a 50/50 mixture of distilled water and a high-quality ethylene glycol coolant recommended by Cummins. Check your owner's manual for specific requirements.

Q: How do I know if the radiator cap is bad?

A bad cap may have a cracked rubber seal, or the pressure tester will show it cannot hold pressure. A failed cap often causes coolant to overflow or boil over.

Q: Will error code 118 clear itself after fixing?

Yes, after repairing the issue and running the generator, the error code should clear. If it persists, you may need to reset the system by disconnecting the battery for a few minutes.

Q: What if I find a leak in the radiator?

Small leaks can sometimes be sealed with epoxy or tape temporarily, but for a permanent fix, replace the radiator. Contact a professional if unsure.

Abstract

Cummins generator error code 118 indicates low coolant pressure. This means the engine coolant system is not maintaining proper pressure, which can lead to overheating. The fix involves checking the coolant level, inspecting for leaks, and testing the radiator cap.