What Tools to Have on a Boat for Engine Maintenance

On boats, engines are a critical lifeline, especially when you live on a boat like we do - our catamaran is our home, and the tender is like our car.

Having the ability to maintain your marine engines can be financially beneficial, and give you peace of mind, but you'll need to have the right tools aboard. Based on what we have and use all the time, here are some of the essential tools I think every cruiser should consider having in order to complete basic marine engine maintenance and repairs.

CONTENTS:

• Why you need the right tools

• What tools to carry

• Servicing spares

• How to service your own marine engines

• Organization

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Why having the right tools matters

Imagine being anchored in a remote bay with no access to a marine mechanic. Your engine sputters, and you’re left with two options; fix it yourself or stay put until help arrives. What do you do?

On our boat we have 3 marine engines in service; two Yanmar diesel's and a Tohatsu outboard. It was important to us to know how to maintain and troubleshoot these engines ourselves, because as liveaboard cruisers we aren't always located places where there's competent marine mechanic available. Part of that equation is having the right tools to get the job done.

What tools to have on a boat for the engines

We have a comprehensive toolkit aboard so it's hard to narrow it down to the key item. That said, here's a list of general tools and equipment I think is useful to have, as well as some engine specific things to consider getting.

General tools and equipment

Starting with the basics, here are the general tools and equipment that we use not just for our engines, but also for numerous other tasks around the boat.

• Fluke multimeter to troubleshoot electrical issues

• Bosch thermal camera to check engine temperature, and for leaks and hot joins

• Metric socket set and rachet

• Metric spanner set

• Adjustable wrench

• Flat head (slotted) and Phillips screwdriver set (We prefer Wiha)

• Electrical rated plier set (We always get Knipex)

• A bag of cotton rags

• A bucket to place used parts while working

• Cleaning solvents like isopropyl

• Trim removal kit with plastic scrapers as they won't damage metal or gelcoat

• Silicone grease, silicone spray, Joker spray and contact cleaner

Some of these tools we already owned before moving on the boat, others, like the thermal camera, were bought because of the boat.

Engine servicing tools

These are some of the tool we keep aboard specifically for working on our engines, as well as the Yanmar SD 60 saildrives our catamaran has.

• Filter wrench

• Torque wrench

• Mechanic pick set

• Manual oil changer (we have had the West Marine one for years)

• Various funnels for filling oil and diesel - the flexible oil funnel is nice to have

• Lower unit gear oil pump for our outboard

• Yanmar impeller puller

• Bearing press kit

Many of these tools are used for other things around the yacht, including installing parts and servicing the generator, windlass, dive compressor and watermaker motor.

Servicing spares to keep aboard

At each servicing interval there's specific parts and fluids that need to be checked and changed, and if something goes wrong it may be one of those that's the root cause of the issue. It's useful to have a selection of spares aboard so that you don't need to mess around with trying to find a dealer. This could include:

• Fuel filter

• Oil filter

• Impeller

• Engine oil

• Coolant

• Anodes

• Exhaust mixer elbow

• Seals and hose

• Spark plug

• Hose clamps

How to service and troubleshoot your marine engines

If you're attempting to service, repair or troubleshoot your engines it's important that you know exactly what you're trying to achieve and the logical steps needed to get there. A small error or misunderstanding could cost you thousands in repairs, not to mention leaving you stranded - this isn't something to approach with a cowboy attitude. Education, attention to detail and having the service manual are some of the best ways around this.

If you're still building your skills you may want to:

• Take a course on marine engine servicing

• Hire a mechanic or experienced cruiser to provide 1:1 lessons

• Self-educate by reading books and watching relevant YouTube tutorials from knowledgeable individuals

• Assist other cruisers in servicing their engines to learn how they do it

It's also smart to source the workshop service manual for your specific engine, as this document will contain all of the specs and details you need to know to service it correctly.

Overall it's advisable to be methodical, think logically through each step, and be careful in your approach (don't panic or rush yourself) to maximize the chances of success.

How to organize and store your tools on a boat

How you store your tools will depend on the size and layout of the boat, but the key is to keep it organized, and away from salt water and sea breeze.

Aboard SV Liger, frequently used tools are organized into a stainless steel tool chest with pull out drawers, while those that have a more specific use, like the manual oil changer, are kept in harder to reach spots.

We keep our engine spares in airtight containers that are kept in the engine bay. Before being stored, each part is noted in a Google Sheet with the part number and how many we currently have. That sheet is updated every time something changes, so we know exactly how many spares we have.

Consumables like marine grease, sprays, electrical tape, hose clamps and thread-locker are kept in a single cupboard inside, and replaced as needed. Engine oil and coolant is in the engine bay, and we always have enough on hand for one full service.