By Charles Fort
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.
Here are six spots on your boat where corrosion can be prevented through proper maintenance and regular inspections
The obvious and the not-so-obvious mistakes that can cause such severe damage, and how to avoid them
Metal parts underwater are subjected to two harmful types of corrosion: galvanic corrosion and stray current corrosion
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.