The jury is still out on that. One of the major issues is the need to keep the fuel mixed—otherwise settling occurs.

They’ve been around a long time now. One advantages is that they’re not succeptible to electrolysis. The biggest problem is lack of maintenance. All thru-hulls need to be exercised occasionally. If I were building a new boat, I’d go with plastic.

A large part of the cost in repowering is the installation. For that reason, a new engine usually makes more sense.

Speed! If you’re a racer, the sprayed bottom will give you a significant competitive edge.

The thru-hulls should be exercised (opened and closed) at least every three months, even those that are normally always closed. Make sure that wooden bungs are close at hand for every thru-hull. Hose clamps should not be rusted beyond utility. Flexible hosing from the thru-hull should be supple and free of cracks.

It depends on the use of the boat. Ablative paint works great if the boat is moving through the water often. Hard vinyl and modified epoxy are great for boats that sit most of the time, or where the bottom is cleaned by scrubbing. Two things to keep in mind with bottom paint. Make sure any new paint is compatible with what’s currently on the boat, and read the manufacturer’s application instructions carefully.

A major cause of rot on wooden boats is fresh water, which combined with with dust accumulation causes mold. The mold attacks the wood. That’s why wooden boats on lakes are pulled out of the water and dry stored. When washing your wooden boat, finish rinse it with salt water if possible.

It’s likely the heat exchanger is plugged up with corrosion and from previous zincs which have partly disolved. The heat exchanger should be removed and brought in for inspection and cleaning.

Check your exhaust for carbon buildup. Once the engine has cooled, remove the exhaust hose from the back of the engine, look into the exhaust elbow and inspect the passages. On some engines, the exhaust elbow may need to be removed for inspection. If the elbow has significant carbon buildup, it needs to be cleaned or replaced. Another indicator of this problem is reduced water flow coming out of the exhaust.

The packinng gland should be adjusted just tight enough so that it’s not leaking at rest. The gland should leak just enough during operation so that it won’t heat up.

The engine oil should be changed at least once a year, and more often with heavy usage. For sailboats, even though the engine may run just a few hours a year, the oil degrades and must be replaced.

Your boat engine should be wiped down with a rag periodically to remove any excess oil or water accumulation. If the oil and water continue to form, the origin should be determined and repaired. A clean engine will help keep your engine running well.

The general rule is the standing rigging should be replaced every 10 years. However, occasional inspections are needed and replacement should be made if any of the following is observed: swedges have cracks; meat hooks are discovered in the wire; or the lay of the wire feels rough.