YANMAR-MARINE-EXHAUST-TEMP critical Yanmar ›

Yanmar Marine Exhaust Elbow Over-Temp Alarm

The YANMAR-MARINE-EXHAUST-TEMP (Yanmar) diesel fault code means: Yanmar Marine Exhaust Elbow Over-Temp Alarm. This is a critical severity code.

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Keep driving?
No -- stop driving
DIY difficulty
advanced
Estimated cost
$100-$2,000
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Common Symptoms

  • Exhaust temp alarm
  • Steam, possible melted exhaust hose

Probable Causes (Ranked by Likelihood)

  • Raw water mixer flow loss (impeller problem) Very Likely
  • Corroded / blocked exhaust riser Likely

Step-by-Step Diagnostic Procedure

  1. Shut down immediately.

  2. Check raw water flow at strainer.

  3. Inspect riser for internal rust scale blockage.

Frequently Asked Questions

What is Yanmar code MARINE-EGT-HIGH?

Yanmar MARINE-EGT-HIGH: Yanmar Marine Exhaust Elbow Over-Temp Alarm. This code is reported on Yanmar equipment running the described engine family.

Can I keep working with Yanmar code MARINE-EGT-HIGH?

Do not continue operating. Risk of engine damage or unsafe shutdown.

How much does Yanmar MARINE-EGT-HIGH cost to fix?

Typical repair cost: $100-$2,000. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Yanmar SmartAssist / YDT) is usually required.

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