Yamaha F225 Corrosion Complaints

By Charles Fort

Owners of some Yamaha outboards are incensed at having to pay thousands to repair their relatively low-hour engines.

Recently, the BoatUS Consumer Protection Bureau has been made aware of dozens of reports regarding serious corrosion problems in Yamaha outboards, specifically 2000 to 2004, first-generation F225 models. Over time — the issue usually surfaces after 500 to 700 hours of use — the engine's exhaust gases appear to corrode the exhaust tube and sometimes the engine's oil pan, which is in the same area. Reinier Van Der Herp, a New Jersey marine surveyor, told BoatUS, "I've seen the damage to six engines myself, and know of at least a dozen others in the New Jersey area." The failure, he reports, isn't outwardly visible, but the engine may lose power and begin to smoke. In some cases, he says, the oil dipstick can be blown out of the engine from the exhaust-gas pressure.

To date, six BoatUS members have reported to us that they've experienced this problem, and we've received similar reports from three other marine surveyors, on both coasts, who have examined this problem firsthand on other boats. In addition, Internet chat rooms and forums describe the experiences of many other owners who have 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 hit to the wallet is labor, which can top $2,500. In some cases, the power head may have to be replaced, which can cost $10,000 (the F225 retails for more than $17,000), or twice that for owners whose boats have two engines.

For its part, Yamaha duly repaired engines that failed during the warranty period. But because most recreational boat owners use their outboard engines less than 100 hours per year, a three-year warranty means that many engines begin failing a year or two after the warranty expires. According to Yamaha, no service bulletins were issued about this corrosion problem, though it appears the company has created a parts kit specifically to address fixing it.

A Case In Point

BoatUS member Steve Oetegenn from San Diego, California, was about to close the sale of his 2004 29-foot Seaswirl with twin 2003 Yamaha 225s, but during the final sea trial, the starboard engine began to smoke and the buyer walked. Oetegenn took the boat to his mechanic and was stunned when told the dry-exhaust corrosion was so severe that the power heads would have to be replaced at a cost of more than $20,000 for both.

The engines had been serviced every year exactly as Yamaha suggested, and in fact had just been serviced a week before at a cost of $2,000. His engines had only 500 hours of use. The frustrating part, says Oetegenn, is that if Yamaha had previously informed the technician of the potential problem, the engines could have been inspected for corrosion during a prior annual maintenance (while still under warranty) and perhaps been repaired, rather than ruined. The worst part? Oetegenn had purchased an extended warranty for both engines, and it had expired only months before the engine failed. Oetegenn wrote two letters to Yamaha to request assistance, and received a letter that said, because his engine was out of warranty, the company was unable to help. He now will have to spend thousands of dollars in repairs, just so he can sell his boat.

Other owners who followed Yamaha's maintenance procedures are also angry. In some cases, their dealers first tried to fault the owners by telling them that the corrosion stemmed from the owner's failure to flush the engine after every use. But according to Paul Logue, a marine surveyor in Scituate, Massachusetts, who's inspected three ruined Yamaha F225 engines, that argument evaporates because the corrosion happens internally where no cooling water is present. "Flushing would have no effect," he says. "In my opinion, there's nothing an owner could've done to prevent serious corrosion from eventually eating through the exhaust system."

Is Ethanol To Blame? Probably Not

Many of the affected engines became damaged shortly after E10 was introduced. Mark Bell, a metallurgical engineer in Sacramento, California, says it’s unlikely that ethanol is the culprit because it typically burns even cleaner than gasoline. The design of a dry exhaust, he says, should take into account the hot exhaust gases from burned gasoline and its potential to corrode the metal. A coating to withstand the gases is basic and not expensive or high tech, he adds. Indeed, the new replacement kit from Yamaha has parts with a different coating that seems to be effective. Another reason ethanol likely isn’t to blame is that other Yamaha products don't appear to be suffering the same corrosion issues.

Yamaha Responds

BoatUS contacted Yamaha by phone and letter to discuss this problem. In a response letter to BoatUS, 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 would not provide further clarification about how flushing the engine would prevent corrosion of the dry exhaust parts. 

From 1906 to 1980, max horsepower ratings grew from around 3 to 300 HP. In 2008 that jumped to 350 HP. just three years later, the new bar was set at 557 HP by Seven Marine.

— Published: October/November 2012

Do You Have A Yamaha 225? Here's What You Need To Know

While it's often possible to have the dry exhaust inspected by dropping the drive leg (no more time-consuming or expensive than getting access to change the water pump), sometimes the damage can only be discovered with a special tool called a borescope that's snaked up inside, and even then the technician has to know what to look for. If damage is found early enough, it may be possible to replace only the damaged exhaust pieces. If the corrosion is too advanced, engine replacement may be the only option. If you have any experience, positive or negative, with Yamaha, or with the corroded dryexhaust sections on your Yamaha 225, please report it to BoatUS Consumer Protection at ConsumerProtection@BoatUS.com.


BoatUS Magazine Is A Benefit Of BoatUS Membership

Membership Also Provides:

  • Subscription to the print version of BoatUS Magazine
  • 4% back on purchases from West Marine stores or online at WestMarine.com
  • Discounts on fuel, transient slips, repairs and more at over 1,000 businesses
  • Deals on cruises, charters, car rentals, hotel stays and more ...
  • All For Only $24 A Year!

Join Today!