Some onboard equipment is all but invisible when we list what service to do during our annual maintenance. Surprisingly, this includes important gear that is ignored until it stops working.

I did a casual survey of friends, and it is not just me. So, I am confident that it may be a universal thing. We all tend to ignore certain gear on our boats. And I suspect I know why.

Some equipment is so reliable and requires so little maintenance, we just don’t give it a second thought, compared to other more obvious things like fuel filters. But the danger, of course, is that at some critical moment when we really need it to function, it may quit or perform poorly.

So, we should include them in our commissioning plans, and make sure they always work well, to keep our cruising safe and enjoyable.

Electric Bow and Stern Thrusters

I have owned several boats with thrusters, and while purists used to complain they are not necessary, having a thruster makes all the difference in many boating situations. As we discussed before, having a stern and/or bow thruster allows a boat with a single engine to maneuver every bit as well as a boat with twin engines. Thrusters give us confidence when wind and current are against us coming into a slip or narrow fairway. Rather than luxury options for big yachts only, thrusters are now standard on many production powerboats, trawlers, and even sailboats. They just make sense and for all the right reasons.

Given that we love thrusters, when was the last time you inspected your bow thruster? It stands ready to help you dock like a pro, but have you checked the space where it is located recently? It is well worth your time to inspect the electrical connections, look for water, corrosion, dust, or anything unusual.

When you think about it, an electric thruster is both an electrical and mechanical machine of moving parts on a boat in saltwater. So how can we possibly think it could be maintenance free?

Years aboard boats with thrusters means I probably used most every thruster manufactured by companies around the world. And I guarantee that each comes with a user manual with a section on maintenance. While thruster models may vary slightly, the recommended maintenance programs from each manufacturer show that an electric bow or stern thruster needs regular attention.

(Seen below: Bow thrusters assist with docking by allowing the captain to move the boat using any easy joystick control.)

bow thrusters

My current day cruiser came with a Side-Power SP 40 thruster. While it is a small boat and the modest unit is self-contained, I still need to check the space under the V-berth for leaks as well as to make sure all electrical connections are tight and corrosion-free. It is also a good idea to make sure the nuts holding the thruster unit to the saddle of the thruster tube are tight. In larger units there is gear oil to change and maintain at the proper level. On bigger cruising boats, thrusters are large and complex.

When I noticed black dust in the small space near the chain locker of our Zimmerman 36, a technician found out why and then replaced the four pairs of brushes in the thruster motor.

Look at the terminals. A rag with contact cleaner is a good way to clean off the terminals, and then use anti-corrosion spray or grease to keep them protected from corrosion in the often damp and unventilated space below the waterline.

It is also important to occasionally check for voltage drop between the thruster terminals and the battery. Some companies suggest annual tests for voltage drop, while Vetus recommends the test every two months during the season if the boat is used a lot. If one finds more than a 10-percent voltage drop between the thruster motor and the battery, there is something amiss. You will need to have a marine technician look and measure each leg of the thruster circuit for resistance.

All thruster manufacturers recommend that the zinc anode on the lower unit be changed at least yearly, or when it is down to half its original size.

Keep the thruster unit space clean, and everything tight. This will do much to ensure the system will work when you need it. Given the heat generated by a thruster, it is also important to keep the space clear of combustible materials, which is usually not hard to do with a bow thruster. But a stern thruster may share space with other gear.

Electric Anchor Windlasses

A properly sized anchor windlass is absolutely necessary for couples who cruise on a large boat, as heavy ground tackle can’t be handled without it. Yet it seems we really do not think about it, as it just works...until it doesn’t.

There are many styles and sizes of anchor windlasses, and all need proper maintenance on a regular basis. Ideal Windlass (now owned by Schaefer Marine) recommends checking the gear case oil level every six months, and removing, cleaning, and greasing the friction plates and wildcat once a year. Every two years the company recommends checking the electrical connections and condition of the rubber covers over the foot switches, as well as changing the gear case oil.

Muir recommends stripping the windlass once a year to clean all moving parts and grease them before reassembling the unit. Maxwell publishes a maintenance guide that lists similar activities at the start of the season, at six months, and at the end of the season. The Maxwell guide has different recommendations among its model line, depending on factors such as whether the windlass components are above or below the deck.

(Seen below: An electric anchor windlass will continue to function properly with the right periodic care and maintenance.)

electric windlass

Lofrans provides a chart of recommended maintenance tasks, based on how many months the boat is used each year, spaced at intervals of 3, 6, 12, 24, and 36 months. For full-time cruisers, it recommends some level of service every three months. The maintenance program includes washing all external surfaces to remove salt layers, cleaning and lubricating all moving parts, replacing gaskets, checking for voltage drop at the terminals, even removing the anchor windlass off the deck to clean the area underneath the windlass before reinstalling and sealing the windlass base.

So, it seems that the beautiful hunk of machinery, that we depend on for keeping us safe when we are cruising, is not something to be overlooked.

If I owned a boat over ten years old, and I planned to go cruising out of home waters, I would probably remove the windlass and send it back to the manufacturer or its repair facility, to have it rebuilt and reconditioned with new internal components as needed. That way, I am assured of shoving off with an essentially new anchor windlass.

While discussing anchor windlasses, why not also look at the anchor and the anchor rode? Recently, a friend bought a used 43-foot Downeast cruiser with big twin diesels. It is a real speed machine that takes him places way faster than the lovely, 54-foot sailboat he owned for years. Both nice boats, but now he loves getting places quickly and says the Ray Hunt-designed hull is smooth and a joy to run at speed.

The boat came with 300 feet of anchor chain for his primary main anchor. He is still learning his new cruising boat, so at the suggestion of a fellow ancient mariner, he pulled all the chain out of the chain locker and spread it out on the dock. He was shocked to see about half of the chain was heavily rusted and probably no longer safe. He salvaged about 175 feet of chain, which is more than adequate for Chesapeake Bay.

I do hope he tied the bitter end of the chain to a length of rope rather than attaching the last link directly to the bulkhead in the chain locker. You do know that, right? In case of emergency, the rope provides a vital cushion to stretch if all 175 feet ran out quickly by accident or gear failure. That has caused extensive damage to boats in the past when the full force of the chain coming taut rips out a structural bulkhead.

This rope should also be long enough to allow crew to cut the rope with a knife if all of the chain and anchor need to be jettisoned quickly, as when the anchor is stuck and the boat is swinging onto a rocky shore and we need to get out of this downhill-spiraling situation right NOW.

For those with a combined chain and nylon rode, inspect the chain-to-rope splice to make sure it is still pliable and not worn or coming apart. After repeated wet/dry cycles, the nylon will shrink and become so tight on the chain it no longer passes easily through the windlass. Better to get this squared away before the boat is out there cruising and you discover it then.

Before I leave this topic, I would like to add that seasonal thruster and windlass maintenance are excellent reasons to develop a solid relationship with a quality service yard. It will have ABYC-certified technicians with the right tools, training, and experience to take care of whatever comes up. While I am a DIY kind of guy, I prefer to let a trusted yard tackle work when it is more than I am comfortable with. Again, we call it pleasure boating for a reason.

And if you do go cruising and have a problem, your yard might be able to assist you if they know your boat, and perhaps recommend a nearby yard that can help you.

Simply put, a boat owner does need to become a Master Wrench if he or she can develop a support system with a quality service yard. While most cruisers can change a belt or filter, they might prefer to let a trained professional adjust a diesel engine’s valves or disassemble a windlass.

There is more to talk about as we prepare our boats for the coming season, but we will save that for the next article. The saying “The Devil is in the Details” was never more fitting than when getting a cruising boat ready for sea.

But for folks like me, that is half the fun…

Continue reading: Preventative Boat Maintenance - Part 2