Yamaha Overhaul Times?

[BillRichardson]

Does anyone have any experience with max run times on Yamaha 4-strokes (specifically 115's) before overhaul, and/or replacement? What are the average high-time hours before they start to crap-out and need replacing? Any thoughts? Hearsay?

Thanks,
Bill Richardson
Scituate, MA
<ainslierich@msn.com>

[Scotia Mist]

Hi Bill,
 I would say that a properly maintained 4 stroke Yamaha would run anywhere between 1500 to 4500 hours. I think the more they are used the longer they last providing that the motors are set up correctly. On recreational boats I think you will more then likely have troubles with attached items failing or corrosion then troubles with internal motor parts. If you figure that if you can put 100 hours a year on a boat in 20 years it will have close to 2000 hours. At that point I surely would keep an eye things to make sure everything was up to par etc.
         I would have any of the Yamaha motors that you are looking at checked out by a qualified Yamaha tech. On most of the newer models (2003+?)  a Yamaha tech can bring up any codes that the onboard computer has stored along with history of the rpms etc. It's something like the OBD that is now being used on the cars. 

 Here is something to keep in minds when looking at any boats. Make sure that the motor/s is reaching the proper RPM at WOT (check the Yamaha website for proper specs). Yamaha motors are very sensitive to over propping. Our motor started making oil. It was due to being over propped. We were only reaching 5000 RPM. I dropped the pitch the oil making stopped. I see that Reed Whitten said his motors were making oil. That is more then likely cause by running a boat that is set up for twins on one motor for extended periods (slower speeds ex sailor). Any boat set up with twins is going to be propped with a steeper pitch to keep the WOT with in specs while running both motors. If you only run one motor it is like trying to start from stop sign with a car in 3 or 4 gear. You lug the motor which is very bad. This creates the carbon build up which can lead to stuck rings etc.  If you do get a Yamaha motor make sure you run Yamaha's Ring Free which is basically a de carbonating/detergent.Cheap insurance with the cost of a newer type OB around 15K .

Also make sure you are happy with the cruise speed of a boat with a single 115. Upgrading to a higher HP motor is a big investment.

     

[BillRichardson]

Hi Barry,

We'd want to upgrade the 115 to a 150, but were looking for what the remaining half-life might be on the 115 so we could build up the piggy-bank prior to spending the buck$. All the feedback is comforting: the engine will last. But, you hit the nail on the head: making sure we're happy with the cruise speed of a single 115? My slow-boat impatience (at least on CAVU days with calm seas), will be the real test!

Thanks for the Info!
Bill & Jean Richardson