Here are some variables that need to be taken into consideration. My boat is loaded heavy, I carry a large deck box with 300+ pounds of gear in it. Lot’s of other fishing gear including power down riggers. My boat has been painted for many years with Petit Hydracoat. The paint is effective but not perfectly smooth. These variables impact performance and efficiency and I suspect a mostly empty 2520XL with no bottom paint would have better numbers then what I see with my now 15+ year old hull. I also almost always have a 160qt cooler onboard and iced down. My boat is a mod-v, notched transom, no bracket. Engine is a 2019 Suzuki DF300APXX with 30” leg. I run 99% of the time in open ocean, almost never calm. All of my data is in nautical miles so statute mile performance would be slightly better. My previous engine was a 2005 Yamaha F225.
What’s absolutely AWESOME with the Suzuki is that the boat performs no different with fuel tank empty or full and seems to ignore having more or less people on board. I can tell you my F225 was a different engine with 1/2 a tank of fuel and just me verse full fuel and a couple of passengers. There were times that it struggled to get on plane. None of this with the Suzuki, regardless of load or sea state, push up the throttle and the boat GOES, jumps up on plane without hesitation. You can feel the power, it is very noticeable compared to the F225 that becomes more apparent the heavier the load or the bigger the wave troughs you need the boat to climb out of.
I have seen 35kts in flat ass calm conditions at WOT and 6000RPMs, trimming for absolute top speed. I can get 32-33kts anytime, regardless of trim setting.
I would say my “fair” MPG is 1.6. at 20-22kt cruise at 4200ish . I see better and I see less but that’s a fair average. Keep in mind, that’s open ocean running, with me trimmed to get as fast of cruise speed in typically rough conditions. Typically trimmed and tabbed down. MPG would absolutely be better in calm conditions but it’s almost never calm. With this engine, the faster I go, the better MPG I get according to the C10s with GPS data. If I cruised at 4800-5000rpm in the high 20s, that’s my best MPG but it’s rarely calm enough for that and I feel more comfortable running the engine for extended periods of time at 4200 rpm then I do 5000.
Lot of words on my part but trying to give you realistic data for my boat in the configuration and conditions I operate in. I could have said 1.6 MPG and 33kts at WOT, that would sound poor compared to a lot of reports I read with much better #s but I don’t think those #s reflect a boat loaded like mine or operating in open ocean condition.
I just finished season two with my 2019 Suzuki 300 DF300APXX. Engine hours at 391. I have removed the lower unit and replaced the water pump myself 2 times. Thus far lower unit has slid in and out without issue (knock on wood). Layout for maintenance is way better then the Yamaha was, the engine is easier to work on. I say this being 100% honest, thus far I have absolutely ZERO regret repowering with this engine. Thus far It has met all my expectations.
