New Yamaha F25

3 things you need to know about the new Yamaha F25 hp Outboard

Yamaha came out with the new F25 “C” engine in 2018.  It replaces the heavier F25 that has been around for years.  The F25C engine is totally new from the gear case up.  It appears that Yamaha’s goal was to offer a lighter weight F25 with fuel injection, and deliver the durability and reliability Yamaha is known for.

  • New Battery-less Electronic Fuel Injection (EFI) Fuel System What does “battery-less” mean?  EFI engines have electrical fuel pumps that are needed to supply fuel to the injectors.  Electrical pumps need battery power to run.  Yamaha’s system is designed to be used on manual start (pull start) engines.  We sold several of these and I can confirm that it does work well.  When we test run these models, once the primer bulb is pumped and the fuel system is filled, 2 pulls of the cord on a brand new engine and it is running.  Since it is an EFI, there is no more manual choke or automatic chokes.  It runs smooth without hesitation, like it should.  The electric start engines start in the same, easy manner.  The effort it takes to pull start the engine was surprisingly low.
  • Variable Trolling Speed-Tiller Handle  All F25 models have this feature.  Tiller models have a switch on them that can control the idle rpms up or down 150 rpms or so without touching the throttle when at idle speed.  This helps to fine tune, and hold specific trolling speeds.  The remote engines have this capability, but an optional VTS switch needs to be installed, OR if a Command link tachometer is used, the VTS function can be controlled via the Command Link gauge.
  • Much Lighter Engine   The previous F25 engine was a solid running engine, but it was heavy.  The new F25 is lighter, and much easier to remove from the boat when necessary.  Owners with smaller boats that were rated for 25hp or more may have been reluctant to go with the previous version F25 because of its weight and how it might affected how the boat sat in the water (stern heavy).  This is no longer an issue.

We’ve sold several of the new F25C engines and these engines have been very reliable. No issues have been reported to date outside of normal maintenance. You can see pricing for each model here: SIM Yamaha F25C



Engine Type 2 cyl
Displacement 432cc
Bore x Stroke 65 x 65.1mm / (2.56 x 2.56 in)
Prop Shaft Horsepower 25 hp at 5500 rpm
Full Throttle RPM Range 5000 – 6000
Alternator Output at W.O.T. 16 amp
Compression Ratio 9.3:1
Fuel Induction System EFI
Weight* 57kg (126 lbs) – 65kg (143 lbs)
Recommended Fuel Octane 87
Recommended Engine Oil Yamalube® 4M (See owner’s manual)
Recommended Fuel Filtration Yamaha 10-Micron Fuel/Water Separating Filter (external)