Yamaha Boat Engines: Corrosion Issues And Affected Years

Yamaha boat engines have been reported to have corrosion issues, particularly in models manufactured between 2000 and 2005. The issue was widely discussed in 2012, with some customers reporting severe corrosion and engine failure after only 500 to 700 hours of use. While Yamaha has not issued a recall, they did create a kit to address the problem, which costs consumers hundreds of dollars to implement. The corrosion is believed to be caused by a defect in the coating of the exhaust components, allowing hot gases to corrode the exhaust passages and leading to potential engine failure.

Yamaha F225 corrosion complaints from model years 2000-2004

Yamaha F225 engine models from 2000 to 2004 have been reported to have corrosion issues. The engine's exhaust gases corrode the exhaust tube and sometimes the engine's oil pan, which is located in the same area. This problem usually surfaces after 500 to 700 hours of use. The failure is not outwardly visible, but the engine may lose power and begin to smoke. In some cases, the oil dipstick can be blown out of the engine from the exhaust-gas pressure.

Several BoatUS members have reported experiencing this problem, and similar reports have been made by marine surveyors on both the east and west coasts. Internet chat rooms and forums also describe the experiences of many other owners who have had similar problems with their Yamaha F225s. One owner, who reported that both his engines failed after only 450 hours, compared the problem to "a youngster needing a hip replacement."

The repair is expensive. A kit with the necessary parts is about $650, but the biggest cost is labor, which can exceed $2,500. In some cases, the power head may need to be replaced, which can cost $10,000 (the F225 retails for over $17,000), or twice that for owners with two engines.

Yamaha has repaired engines that failed during the warranty period. However, as most recreational boat owners use their outboard engines for less than 100 hours per year, a three-year warranty means that many engines start to fail a year or two after the warranty expires. According to Yamaha, no service bulletins were issued about this corrosion problem, but the company appears to have created a parts kit to address it.

BoatUS member Steve Oetegenn, from San Diego, California, was about to sell his 2004 29-foot Seaswirl with twin 2003 Yamaha 225s. However, during the final sea trial, the starboard engine began to smoke, and the buyer walked away from the sale. Oetegenn took the boat to his mechanic and was told that the dry-exhaust corrosion was so severe that the power heads would have to be replaced at a cost of over $20,000 for both. The engines had been serviced every year per Yamaha's recommendations and had only 500 hours of use. Oetegenn had also purchased an extended warranty for both engines, but it had expired just months before the engine failed. Oetegenn wrote two letters to Yamaha requesting assistance but received a letter stating that because his engine was out of warranty, the company was unable to help.

Other owners who followed Yamaha's maintenance procedures have also expressed anger. In some cases, their dealers first tried to blame the owners, telling them that the corrosion was due to their failure to flush the engine after each use. However, according to Paul Logue, a marine surveyor in Scituate, Massachusetts, who has inspected three ruined Yamaha F225 engines, flushing would have had no effect because the corrosion occurs internally, where no cooling water is present. "In my opinion, there's nothing an owner could've done to prevent serious corrosion from eventually eating through the exhaust system," he says.

It is unlikely that ethanol is to blame for the corrosion, as it typically burns cleaner than gasoline. The design of a dry exhaust should take into account the hot exhaust gases from burned gasoline and the potential for these gases to corrode the metal. A coating to withstand these gases is basic and not expensive or high-tech. Indeed, the new replacement kit from Yamaha includes parts with a different coating that seems to be effective. Additionally, other Yamaha products do not seem to be suffering from the same corrosion issues.

When BoatUS contacted Yamaha to discuss the problem, the company sidestepped the corrosion issue and wrote, "The outboards you mention have been out of warranty for quite some time. We would like to remind our customers that the best way to prevent the issues encountered is to flush the motor after every use with plenty of fresh water." Despite repeated requests from BoatUS, Yamaha did not provide further clarification on how flushing the engine would prevent corrosion of the dry exhaust parts.

Yamaha's reaction to the corrosion issue

Some customers have reported mixed experiences with Yamaha's handling of the issue. While some have received support and guidance from Yamaha representatives, others have faced long wait times for repairs and felt that the company was not standing behind its products. There are also reports of customers taking matters into their own hands, attempting to fix the corrosion issue by welding aluminium patches over the perforated casing.

The corrosion issue appears to be isolated to certain models, specifically the F200, F225, and F250, with model years 2000-2004 being the most commonly mentioned. The problem is attributed to a combination of high heat, excess acidity in the exhaust, and exposure to seawater, leading to severe and expensive damage.

Despite the backlash and criticism, Yamaha has not issued a recall for the affected engines. This has led to dissatisfaction among customers, with some stating that they will not repower their boats with Yamaha engines in the future. However, it's worth noting that Yamaha mechanics have provided insights into the cause of the issue, blaming it on the corrosion coatings used to protect the exhaust manifolds.

The corrosion issue's impact on resale value

Yamaha's corrosion issues have had a significant impact on the resale value of their boat engines. The issues primarily affected the company's first-generation F-Series four-stroke outboard motors, manufactured between 2000 and 2005. The problem was severe corrosion and pitting of the exhaust passages, which led to premature engine failure. This resulted in a loss of power and, in some cases, expensive damage that was not worth the cost of repair.

The impact of these corrosion issues on resale value is evident from customer reactions and experiences. Many customers expressed disappointment and frustration with Yamaha's handling of the situation, feeling that the company should have issued a recall for what they considered to be a known engineering defect. Some even vowed not to repower their boats with Yamaha engines due to the company's lack of response and shoddy treatment of customers.

The financial burden of addressing the corrosion issues also affected resale value. Customers had to incur significant costs for repairs, with some reporting expenses of up to $5,000. This created a situation where owners of affected engines were left with the choice of either paying for costly repairs or selling their boats with the corrosion problem, which would likely result in a lower resale value.

Additionally, the corrosion issues caused a loss of trust in Yamaha's products and brand reputation. Customers questioned the reliability and durability of Yamaha's boat engines, which are crucial factors in the marine industry. This loss of trust could potentially lead to a decrease in resale value as buyers may be hesitant to purchase Yamaha engines due to concerns about corrosion and the company's response to the issue.

To address the corrosion issues and maintain the resale value of their boat engines, Yamaha offered a kit designed to correct the problem. However, this kit was not provided for free, and customers had to bear the cost of purchasing and installing it, adding to the financial burden. Despite these efforts, some customers still experienced engine problems, indicating that the kit may not have been fully effective in resolving the corrosion issues.

The root cause of the corrosion issue

Yamaha's first-generation F-Series four-stroke outboard motors (model years 2000–2005) were found to have corrosion issues. The problem was linked to a manufacturing or design defect in the coating of the exhaust components, which allowed hot gases to corrode the exhaust passages. This, in turn, led to holes in the passages, resulting in a loss of horsepower, smoking, and engine failure.

The issue was believed to be caused by a combination of high heat and excess acidity in the exhaust, which ate away at the aluminium. The exhaust passage, similar to a car's exhaust pipe, does not have cooling water running through it. However, as the exhaust ultimately exits through the propeller, the exhaust passage is exposed to splashed saltwater, especially if the engines are mounted low and the boat is in choppy water. As the boat bobs up and down, saltwater can splash up the exhaust, drying out when the engine is started.

The corrosion issue was found to be more severe at the top of the exhaust system, around the oil pan, rather than at the bottom. This led to speculation that Yamaha used multiple suppliers for the castings or casting material, and that the aluminium used may have contained zinc, which is highly susceptible to corrosion.

It is worth noting that not all Yamaha motors were affected by this issue, and the company has not issued any technical service bulletins or recalls. However, they did create a kit to try to correct the problem, which consumers had to pay for, in addition to the cost of implementing it.

Yamaha's corrosion protection products

Yamaha offers a wide range of marine maintenance products designed to protect boat engines from corrosion and wear-and-tear. Here are some of the Yamaha marine corrosion protection products available:

Yamalube External Engine Cleaner/Degreaser

The first step in protecting your marine engine is to keep it clean. Yamaha’s external engine cleaner and degreaser are designed to remove dirt, oil, and grease from your motor. It not only protects against corrosion but is also safe to use on most rubber, plastic, and painted metal surfaces.

Yamalube Silicone Protectant and Lubricant

After cleaning your engine, you can apply Yamaha’s silicone protectant and lubricant, a versatile spray that encapsulates all of the different exposed metal parts of your engine and protects them from rusting. It also provides protection for neoprene, rubber, and other surfaces.

Yamalube Rust & Corrosion Protection

Yamalube’s rust and corrosion protection spray, also known as Yamashield, provides premium protection against rust and corrosion using a combination of solvents, lubricants, and waxes. This waterproof spray combats existing corrosion and provides long-lasting lubrication for all engine components, not just metal parts.

Yamalube Combustion Chamber Cleaner

Yamalube’s combustion chamber cleaner is designed to remove carbon-based contaminants from valves, rings, cylinders, and pistons. By preventing carbon build-up, it helps to keep your engine running smoothly and efficiently. It also cleans out gum and varnish from the engine, helping to prevent damage over time.

Yamalube Engine Fogging Oil

If you’re storing your boat for the winter or for an extended period, Yamaha’s engine fogging oil will protect your engine from rust and corrosion. This oil is highly recommended for outboard winterization as it provides long-term protection by keeping engine parts lubricated during storage.

Yamalube EFI Engine Storage Fogging Oil

For those with a fuel injection system, Yamaha offers the EFI engine storage fogging oil. This oil has a special lubricant with a fuel stabilizer that equally distributes fogging oil to cylinders in EFI engines. It prevents salt water, combustion acids, and moisture from damaging pistons, valves, and cylinder walls while the boat is in storage.

Yamalube Battery Terminal Cleaner and Protector

Yamaha’s battery terminal cleaner and protector is a water-based spray that removes corrosion and leaves a protective film behind, acting as a shield against further corrosion.

Yamalube Marine Grease

Yamalube’s marine grease is a multi-purpose grease that is highly resistant to water and provides superior lubrication to keep marine parts functioning optimally. It repels both freshwater and saltwater corrosion, protects metal components from high temperatures and heavy shock loads, and prevents seals from deteriorating.

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