If you keep your boat in the water, these simple steps can help prevent engine damage and save you money. Do you keep your boat in the water during the season like thousands of other boat owners? Maybe you live in one of the southern states and keep it in a slip year-round. Regardless of your circumstances, if your boat stays in the water for extended periods of time, there is one simple procedure you should perform after each outing. This important task can prevent lost boating time, save money on unnecessary repairs, and keep lubricants out of the marine environment. If you’re like many of your fellow slip-bound boaters, you probably forgot all about it after initially reading the operating instructions in your outboard owner’s manual.
Pete Reils is a Yamaha Master Technician who works at Garden State Marina in Pt. Pleasant Beach, New Jersey. Recently, he was changing two of the four trim seal and ram assemblies on a large center console boat powered by twin Yamaha F350 outboards. The assemblies are part of the hydraulic power trim and tilt units, a system that is integrated into most Yamaha outboards over 50 horsepower. On larger outboards, each engine has one long ram for the tilt function, which raises the engine out of the water when not in use, and two shorter rams that trim the engine up or down during operation to fine-tune the boat’s ride and fuel economy. It’s a dependable system designed to provide years of trouble-free service.
“This is one costly repair that we should never have to make,” said Reils as he showed one the damaged ram assemblies alongside the new replacement. Corrosion had eaten away at the stainless steel shaft where it passes through the seal. “Sometimes corrosion like this can be caused by prolonged exposure to saltwater. If the boat is left unused for extended periods of time, the rams can even become fouled with barnacles. Whether it’s fouling or corrosion (figure 1), the rough spots on the shaft ultimately damage the seal allowing pressurized hydraulic fluid to leak out of the cylinder and water to permeate into it.”
Figure 1
So what’s the answer to preventing this all-too-common problem? Maybe it’s easiest to start with another question. When you return to the dock after using the boat, what’s the last thing you do before you leave? Most will answer that they tilt the engine all the way up so it is out of the water. However, there is one more important step to take to protect your outboard.
Figure 2
Once the outboard is fully raised, walk back to the engine and drop the retractable engine rest into position (figure 2), then press the power trim and tilt control button at the helm or on the side of the engine to fully retract the trim rams back into the cylinders until just the tips are visible (figure 3). In this position, the rams will be protected and lubricated no matter how long the boat is idle. The whole procedure takes less than a minute, but failing to do so can lead to unnecessary repairs, lost time on the water and can cause hydraulic fluid to leak out of the system into the environment.
Figure 3
Another cause for concern for boaters who wet-store their boats is damage due to galvanic corrosion
Your Yamaha outboard comes equipped with sacrificial anodes, commonly called zincs (figures 4 & 5), which help prevent this form of corrosion. The anodes are designed to be the first metal to sacrifice itself, thereby protecting other parts.
Figure 4
By nature, the anodes have a life span that can vary with the environment around your boat and they should be checked periodically. If you notice that they have corroded to a point where their integrity could be compromised, have them replaced promptly. They are cheap insurance against possible corrosion to the expensive parts of your outboard’s lower unit.
Figure 5
Keeping your boat in the water at a marina or in a slip in your backyard does not have to be a problem as long as you follow proper storage procedures and maintain the basic systems designed to keep your engine operating at peak performance.
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