Makboatworks

Makboatworks  partners with the OCEAN POSSE

 

 

a Yanmar 4JH

By Mike Keller, Makboatworks

I’m in Virginia having tacos with my kids when the phone rings. It’s my clients and Ocean Posse members, Tim and Gretchen on S/V Felicità. They are five miles from rounding Cabo Corrientes in Mexico and I can hear the shrill sound of an engine alarm in the background.

I meticulously prepared the engine back in San Diego before Felicità set off for Mexico in 2022 and now it’s overheating. Before they called, they did the obvious things: checked the impeller, checked the coolant, checked the oil, and looked for leaks. That’s when they picked up the phone and called me, their virtual ‘life line,’ and the virtual troubleshooting began.

I always start with the obvious. Perhaps they picked up something that’ll shake loose when they restart. While they were a bit nervous to restart the engine, Tim turned the key. Water was flowing out of the exhaust, and I hear them breathe a sigh of relief, chalking it up to a minor hiccup. I bid them fair winds and went back to my kids and our tacos… for a few minutes. The phone rings again, and Tim is on the phone with that darn alarm blaring in the background.

I asked them to  inspect the water pump.  The raw pump was showing no leaks, the bearings are fine, and the impeller looks perfect—no missing fins or signs of separation from the bushing. It doesn’t add up. They decided to turn back for La Cruz under sail and then the deep trouble shooting began.

Back at the dock, I had them test the water pump. Everything seemed fine. Water was flowing steadily, and the engine was running without overheating. Convinced it was a fluke, I suggested they go for a test sail. For a while, everything ran smoothly. Then, 30 minutes in, the temperature climbed, and the water flow stopped—again.

Uncovering the Culprit

After exhausting the usual suspects—through-hull blockages, impeller issues, and the cooling system, I suggested they inspect and clean the heat exchanger—which they did with the help of a local mechanic in La Cruz. They also took a look at the exhaust system (replaced during the 2022 refit) everything  looked fine. But that darn alarm was still sounding. This left only one thing: the water pump itself. A rebuild or replacement seems inevitable.

So after I talked Tim through removing the raw water pump, the mystery unraveled. The gear driving the pump and the flywheel had worn teeth—but not in the way you might expect. Both sets of teeth were worn on the edges, a telltale sign that the pump’s gear had been installed backward.

What’s more surprising? The pump had never leaked, and regular maintenance showed no red flags. The impellers had been replaced routinely, and general servicing was diligently performed. This issue, hidden in plain sight, had been waiting since before Tim and Gretchen bought the boat. It likely stemmed from a repair by a previous owner, overlooked and untraceable until now.

Fortunately, prior to departure Gretchen asked me to give them a list of suggested spares to carry so they had a spare raw water pump onboard and using What’s App and Facetime I was able to support them from afar.

What we learned

This Yanmar 4JH incident with my clients on Felicità serves as a reminder that even seasoned boaters can learn something new. With every challenge comes wisdom, and with every surprise, an opportunity to become a better, more resilient sailor.

So, what’s the takeaway from this experience? No matter how carefully we planned setting up their boat for cruising or how diligently they kept up on the service of their systems, unexpected problems can still arise. Wild cards like this teach us to dig deeper and inspect the less obvious.

Here are a few key lessons:

• Don’t Assume: A “new-to-you” boat deserves a thorough inspection, even of components that seem to be working fine. Remove and inspect the water pump as part of your first deep dive into the engine.
• Take Pictures: Before removing any part, take photos of its orientation. It’s a simple way to ensure you can reinstall correctly or identify prior mistakes.
• Expect the Unexpected: Preventative maintenance is critical, but it doesn’t eliminate every possible failure. Staying prepared for surprises and carrying the right spares is part of the boating experience.

Next time you’re out on the water, remember: every hiccup is a chance to grow, troubleshoot, and, ultimately, enjoy the adventure of boating.

Photos

The water pump with worn gear teeth:

 

 

 

 

Flywheel damage inside the engine housing:

Comparison of the old water pump (left) with the new one (right):

 

 

 

 

 

ABOUT  Makboatworks

Marine Consulting and Emergency Response for Cruisers

– Supporting sailors with 25 years of expertise
– Custom solutions tailored to your budget and cruising lifestyle

Mission

Empowering Sailors to Maintain and Upgrade Their Vessels

– Delivering practical knowledge for confident cruising
– Providing support to ensure safe, enjoyable, and cost-effective journeys

Key Features Overview

1. Boat Assessments for Cruisers
2. Proactive Maintenance Solutions
3. Emergency Lifeline Support
4. Repair Guidance and Support

Feature 1 – Boat Assessments

– Comprehensive evaluations to align your boat’s systems with your cruising goals.

– Understand existing systems and plan upgrades for simplicity and functionality.

– Focus on maintaining systems that are easy for owners to operate and repair.

Feature 2 – Preventative Maintenance

– Minimize downtime and expenses with proactive strategies.

– Faster issue diagnosis keeps you cruising longer for less.

– Practical, budget-friendly solutions tailored to your needs.

Feature 3 – Emergency Lifeline

– 24/7 remote phone support for at-sea emergencies.

– Step-by-step guidance for on-the-spot repairs.

– Helping you reach port safely with practical repair strategies.

Feature 4 – Repair Guidance

– Support for DIY repairs, with detailed step-by-step guidance.

– Expert advice to ensure professional repairs are done correctly.

– Assistance with parts sourcing to avoid costly mistakes.

Why Choose Makboatworks?

– 25 Years of Industry Experience: Trusted expertise in marine systems.

– Custom Solutions: Tailored to your lifestyle, budget, and vessel.

– Comprehensive Support: From understanding your boat to emergency assistance.

– Passion for Sailing: Helping cruisers enjoy worry-free adventures.

• Contact Information
• Mike Keller – Founder
• Email: Makboatworks@gmail.com
• Phone: 619-757-9487
• Website: www.Makboatworks.com

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by admin