YANMAR-MARINE-FUEL-PRESSURE serious Yanmar ›

Yanmar Marine Fuel System Low Pressure

The YANMAR-MARINE-FUEL-PRESSURE (Yanmar) diesel fault code means: Yanmar Marine Fuel System Low Pressure. This is a serious severity code.

My Garage →
Keep driving?
Limited driving only
DIY difficulty
intermediate
Estimated cost
$30-$400

What Are the Symptoms of YANMAR-MARINE-FUEL-PRESSURE?

  • Surging at cruise
  • Shutdown under load

What Causes YANMAR-MARINE-FUEL-PRESSURE? (Most Likely First)

  • Plugged primary (Racor) fuel filter Very Likely
  • Air ingress from loose fitting / cracked hose Likely
  • Failed electric lift pump Possible

Can I Still Drive with YANMAR-MARINE-FUEL-PRESSURE?

Limited driving only. YANMAR-MARINE-FUEL-PRESSURE is rated serious severity. Keep trips short and get it diagnosed soon rather than waiting for symptoms to worsen.

Frequently Asked Questions

What is Yanmar code MARINE-FP?

Yanmar MARINE-FP: Yanmar Marine Fuel System Low Pressure. This code is reported on Yanmar equipment running the described engine family.

Can I keep working with Yanmar code MARINE-FP?

Limited operation only -- finish the current task then shut down for repair.

How much does Yanmar MARINE-FP cost to fix?

Estimated repair cost: $30-$400. Off-road diesel shop labor runs $125-$175/hr in 2026. Dealer diagnostic software (Yanmar SmartAssist / YDT) is usually required.

Mechanics Guide Step-by-step diagnosis

How Do You Diagnose YANMAR-MARINE-FUEL-PRESSURE?

  1. Replace primary Racor filter; note vacuum gauge reading.

  2. Smoke-test suction side of fuel system.

  3. Test lift pump pressure.

Which Vehicles Commonly Get YANMAR-MARINE-FUEL-PRESSURE?

  • Hunter / Beneteau / Catalina sailboats with Yanmar 3JH / 4JH
  • Trawlers and sport fishing boats with Yanmar 6LY / 6LF series
  • Sailboat auxiliaries with Yanmar 2YM / 3YM / 3JH5 diesels
  • Commercial fishing vessels with Yanmar 6LY3-UTP
  • Yachts with Yanmar 6LY400 / 6LY440 / 8LV common-rail marine diesels
  • Workboats with Yanmar 4LV / 4JH series marine propulsion
  • Ski boats and express cruisers with Yanmar marine diesels
  • Tenders and RIBs with Yanmar 3YM20 / 3YM30 sailboat aux
  • Island-hopper ferries with Yanmar 6AYM / 6HYM commercial series
  • Tug boats and small workboats with Yanmar 6HAL-HTP / 6HYM

Explore More

Was this helpful?

Send this to whoever is fixing the truck — your tech, or the person asking what the fault means.