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Random Quote: The fish are smaller here but . . . there's less of 'em
I was looking at a triton 240 lts with this engine and was wondering if anyone has had any experience with the engine. It looks sweet but how is it on gas and reliability. It got a 3 star emissions rating which I thought was pretty good. I asked the salesman what kind of gas mileage it got at cruise and he said it would get 2mpg at 3800rmp. I would think that it being an opti, it would do better than that. Is it going to suck that much more fuel because it is a 250. Also, what is the difference in this engine and a regular optimax. Thanks for any input.
Great engine...now will run 87 octane vs last year would only use 92+. This year beafed up the lower unit gears. Gas milage is about the same as 225 opti. This engine has solid engine mounts and seem to shake the boat just a little at idle. Hope it helps.
That thing is a beast. Paper thin cowling and VERY noisy, but if you want to get from A to B FAST, that is the motor for you. A buddy got a pair, the dyno tags on the lower unit on delivery both read 272HP
Have a 2003 on a 25 Fountain. Awesome engine. I see right at 3 mpg at 30 mph on Floscan and GPS fully loaded. The key differences between the 225 and 250 Opti are all somewhat minor performance features that add up. The engines are assembled by Mercury Racing with these key changes;
heads are different
intake tract air flow increased
reed valves are rubber coated
compression slightly higher
PCM fuel tables and timing modified
How do the Yamaha 300's compare to the 250SX? even though the SX is a 250, I'm guessing it out performs the 300 Yamaha, but I don't have anytime with the Yamaha.
I looked at some other post on here about the 250xs and they say that the 250 will eat that yamaha up. I am not a big fan of the yamaha 250 and 300 hpdi block anyway. I am wondering now if that 250 would make it tough to slow troll (1-2mph) if it is that fast. Would it be able to slow down enough at idle to acheive these kinds of number. Its hard to pull live bait at 3-4-5 mph. It just kills them
250 xs 2005 and older requie 93 octane. they are very reliable and great on gas. very powerful and just allround awesome engines - super fast. the 225 opti is one of if not the most bullet proof direct injection engine available. GO OPTIMAX!!!!!!!!!
uncwredfisher - 10/5/2005 10:59 AM I looked at some other post on here about the 250xs and they say that the 250 will eat that yamaha up. I am not a big fan of the yamaha 250 and 300 hpdi block anyway. I am wondering now if that 250 would make it tough to slow troll (1-2mph) if it is that fast. Would it be able to slow down enough at idle to acheive these kinds of number. Its hard to pull live bait at 3-4-5 mph. It just kills them
You should be fine. Idle speed is 600 rpm and if you troll with one engine, with the other engine turned off and in gear, you can can rest assured you will not be going too fast for live baiting.
Hey tireless, the boat only has one engine is the thing. Its 24 ft and probly weighs around 2500-3000lbs loaded is my estimate. It is a bay boat. Thanks
You should still be fine....what will make a difference will be the props you run on the boat. I have seen guys with too much engine and prop to: 1) lower trim tabs to slow a boat; and 2) drag a 5 gallon bucket while trolling. The other approach is to bump troll....taking the boat in and out of gear to make it almost hold still in the water.
The 250XS will idle like a sewing machine at 570 rpm in gear all day long. The idle setting is contolled by the ECM for 570 in gear and is non adjustable. If that is too fast for you then any other engine will be worse. I know of no other engine except the 225 Opti that idles that low.
The downside is the noise, at speed they are way too loud for me. The exhaust alone is loud but Merc also chose to put zero insullation in the cowling. Maybe they will quiet her down a bit, they did change to regular fuel on the 06 models.....Going from a Honda 225 to this thing has been a sound shocking experience but the engine run quality and torque output is outstanding.
You might guess that the 250XS would eat up the 300 Yami, but you would be very wrong. In fact if the Merc 300x can't do it, why would the 250XS be able to? In INDEPENDENT tests on identical boats, set up with single motor applications, the 250XS is less than 1 mph faster than the Yami 250. That was when the 250XS was using Premium fuel.
In different test the the Yami 300 was 4 - 5 MPH faster than the Yami 250. Hence, it stands to reason the Yami 300 is approx 3-4 MPH faster than the 250XS in a single engine application.
Head to head the Merc 300X is just over 1 mph faster than the 300 HPDI Yamaha on identical boats during head to head INDEPENDENT testing, and that was with Yamaha forced to use their own prop. Everyone knows Merc makes the faster/better props. Are you saying the 250XS is faster than the Merc 300X????
The INDEPENDENT dyno tests I have seen always put the 250XS between 265-268hp. I would trust it far more than Mercs results, but they are not far from the 272 mentioned.
That said, the 250XS is a great motor but it has three drawbacks: 1) Before 2006 they used Premium fuel 2) They are noisy 3) pre-2006 had poor corrosion resistance and had to have the lower unit ripped off every 6 months or so to keep it from seizing on. I don't know if 2006 models addressed this issue.
You should see approx 3 MPG at cruise on the setup (LTS 240) you spoke about.
I will agree with your conclusion that both Merc 250XS and 300X are faster than both Yamaha 250 and 300 HPDIs.
Quote:
Flat Out Charters - 10/5/2005 7:09 PM
You might guess that the 250XS would eat up the 300 Yami, but you would be very wrong. In fact if the Merc 300x can't do it, why would the 250XS be able to? In INDEPENDENT tests on identical boats, set up with single motor applications, the 250XS is less than 1 mph faster than the Yami 250. That was when the 250XS was using Premium fuel.
In different test the the Yami 300 was 4 - 5 MPH faster than the Yami 250. Hence, it stands to reason the Yami 300 is approx 3-4 MPH faster than the 250XS in a single engine application.
Head to head the Merc 300X is just over 1 mph faster than the 300 HPDI Yamaha on identical boats during head to head INDEPENDENT testing, and that was with Yamaha forced to use their own prop. Everyone knows Merc makes the faster/better props. Are you saying the 250XS is faster than the Merc 300X????
The INDEPENDENT dyno tests I have seen always put the 250XS between 265-268hp. I would trust it far more than Mercs results, but they are not far from the 272 mentioned.
That said, the 250XS is a great motor but it has three drawbacks: 1) Before 2006 they used Premium fuel 2) They are noisy 3) pre-2006 had poor corrosion resistance and had to have the lower unit ripped off every 6 months or so to keep it from seizing on. I don't know if 2006 models addressed this issue.
You should see approx 3 MPG at cruise on the setup (LTS 240) you spoke about.
I asume you are being humurous, or maybe I was unclear. All in all it doesn't matter what my conclusion is, or the common misperceptions, ... the facts speak for themselves:
250XS is approx. a half mph faster than the 250HPDI on identical single engine boats
The 300 HPDI is 4-5 mph faster than than the 250 HPDI on identical single emgine boats
The 300X is just over 1 mph faster than the 300 HPDI on identical single engine boats
There is no need to listen to what people think or have heard, ... I will trust scientific test data over people's hunches and beliefs any day!
where do you guys find test results for independent dyno tests? lots of numbers get thrown around here but i've never been able to find test results online.
You might guess that the 250XS would eat up the 300 Yami, but you would be very wrong. In fact if the Merc 300x can't do it, why would the 250XS be able to? In INDEPENDENT tests on identical boats, set up with single motor applications, the 250XS is less than 1 mph faster than the Yami 250. That was when the 250XS was using Premium fuel.
In different test the the Yami 300 was 4 - 5 MPH faster than the Yami 250. Hence, it stands to reason the Yami 300 is approx 3-4 MPH faster than the 250XS in a single engine application.
Head to head the Merc 300X is just over 1 mph faster than the 300 HPDI Yamaha on identical boats during head to head INDEPENDENT testing, and that was with Yamaha forced to use their own prop. Everyone knows Merc makes the faster/better props. Are you saying the 250XS is faster than the Merc 300X????
The INDEPENDENT dyno tests I have seen always put the 250XS between 265-268hp. I would trust it far more than Mercs results, but they are not far from the 272 mentioned.
That said, the 250XS is a great motor but it has three drawbacks: 1) Before 2006 they used Premium fuel 2) They are noisy 3) pre-2006 had poor corrosion resistance and had to have the lower unit ripped off every 6 months or so to keep it from seizing on. I don't know if 2006 models addressed this issue.
You should see approx 3 MPG at cruise on the setup (LTS 240) you spoke about.
+
I would be very interested to see this data. Can you tell me where to find the publication that these independant tests are available?
Mercury 250XS? 
