228 performance

[fathergoose]

This is a update of an older post from last year. I have a 2009 228 with a Yamaha 250 4 stroke. The boat has a hardtop and the bottom is painted but very clean, boat is kept in a high and dry and the bottom is power washed after every use. It will turn between 6000 and 6100 RPMs but I'm only getting 38 MPH. It doesn't make much difference with curtains off. The prop is a 15 1/2 x 17 and I had it checked and it is in spec. The only thing that I can think of at this point is the motor mounting height. Its at the top hole right now. Any thoughts or suggestions would be appreciated.

Thanks

 

[DennisG01]

I have the same HP (although 2-stroke), so there could be some gearing difference between the two lower units. However, I have a 24' boat and am also running a Yamaha 17" wheel. I top out at right around 5,500RPMs and 40MPH (on gps). Maybe you should be running a 19"?

-- Speed is GPS verified?
-- Look at the anti-ventilation plate when running on plane - it should be just skimming the surface of the water. However, lowering the engine will only cause more drag. If you were too high, you would get ventilation and I'm sure you would have mentioned that.

What's the RPM MAX spec for your engine? If it's also 5,500, then I'd say you are underpropped.

 

[Parthery]

4 stroke rpm range is 5-6K so you are on the money.

Is this speed GPS or from the pickup in the lower unit?

 

[fathergoose]

Speed is per GPS and I confirmed that it is set to MPH

 

[Ky Grady]

Just got back from the lake and I ran 41 mph/GPS @ 6K with a F225. 50 gallons of fuel, 2 people, no curtains, no bottom paint. But my motor is in 3rd hole from top. If you're in top hole, motor is mounted a little low. Grady spec is second hole from top. I'm spinning a 4 blade PowerTec prop.

 

[DennisG01]

I didn't realize I read your original initial post about holes backwards until I just read KY's post. You may have already figured out my response didn't make sense. Yes, raising the motor is a good idea - but also take a look at the anti-vent plate like I mentioned before doing so.

 

[wrxhoon]

I have a 4.2 250 hp , I get about 46.5 mph @5900 rpm running Yamaha 17" pitch prop motor is on the second hole. This is speed on GPS on flat water, clean bottom boat, hardtop 350 lts fuel ( 92 gal) .
I think your engine would have 2.0 gear case and as you are getting over 6000 RPM you could go 18" or even 19" prop , 18" should give you extra 2 mph and 19" 3 mph with fewer Revs. If you are running out on rough seas ( swell) I would go to 18" so you have the torque to go over the waves.
KY are you running 19?

 

[SmokyMtnGrady]

I had the 3.3 liter F250 and the boat topped out at 42 with a powertec 4 blade prop. I bet the motor is too low. I now have the 4.2 on it and KY noticed my motor was mounted on the top hole and I had the motor moved to the second hole. It runs much better. We often focus on top speed. However, with the motor mounted too low you will impact fuel economy as there is more drag.

 

[Ky Grady]

I have a 4.2 250 hp , I get about 46.5 mph @5900 rpm running Yamaha 17" pitch prop motor is on the second hole. This is speed on GPS on flat water, clean bottom boat, hardtop 350 lts fuel ( 92 gal) .
I think your engine would have 2.0 gear case and as you are getting over 6000 RPM you could go 18" or even 19" prop , 18" should give you extra 2 mph and 19" 3 mph with fewer Revs. If you are running out on rough seas ( swell) I would go to 18" so you have the torque to go over the waves.
KY are you running 19?

The go to prop on our motors for Yamaha has been the 15 1/2 x17,,,, going to a 4 blade you step down in pitch because of the extra blade and usually compromise on top end. But in my case, being in the 3rd hole and 4 blades seems to be a sweet spot for me. To get 40-41 out of a F225 is great with a heavy boat. I do lack on mid range grunt with the F225, but the 4 blade helps with that some.

I'm spinning a PowerTech 15 1/4 x 16 OFS4 prop. When I first bought my boat I reached out to Ken at PropGods and discussed what I was looking for out of my setup. He recommended this prop and it has been fantastic. Ken is a wealth of knowledge for propping your boat if you need a prop. Nice guy and easy to talk with.

 

[SmokyMtnGrady]

Remember, the weight difference of losing pounds between the 3.3 and 4.2 motors is enough to warrant only being on the second hole for the 4.2 . When I moved the motor up one hole the skeg is now almost completely out of the water.

I also liked the 4 blade prop more than the 3 blade.

 

[wrxhoon]

The go to prop on our motors for Yamaha has been the 15 1/2 x17,,,, going to a 4 blade you step down in pitch because of the extra blade and usually compromise on top end. But in my case, being in the 3rd hole and 4 blades seems to be a sweet spot for me. To get 40-41 out of a F225 is great with a heavy boat. I do lack on mid range grunt with the F225, but the 4 blade helps with that some.

I'm spinning a PowerTech 15 1/4 x 16 OFS4 prop. When I first bought my boat I reached out to Ken at PropGods and discussed what I was looking for out of my setup. He recommended this prop and it has been fantastic. Ken is a wealth of knowledge for propping your boat if you need a prop. Nice guy and easy to talk with.

Mine came with a Yamaha 17" pitch nut I have lower ratio gearcase 1.75. I thought 3.3 lt has 2.0 gears. 17" in my boat seems about right as I'm getting close to max RPM range. I'm going to try a different prop, I have Mercury Enertia, 17 and 18, I will try them both.
In my old boat I found the 18" was best , I had a 250 Merc optimax and the boat was lighter because I didn't have hardtop.
I may add that this boat/motor combination uses more fuel than the old boat, makes sense , heavier boat.

 

[fastexas]

Just got back from the lake and I ran 41 mph/GPS @ 6K with a F225. 50 gallons of fuel, 2 people, no curtains, no bottom paint. But my motor is in 3rd hole from top. If you're in top hole, motor is mounted a little low. Grady spec is second hole from top. I'm spinning a 4 blade PowerTec prop.

Ky...just did another speed test myself this weekend.....'05 225 Tourney (same hull as yours, probably lighter though). 3-blade 15 1/2 x 17 SS (not in pristine condition) on original '05 F225.
Just me (210 lbs), 1/4 tank, 88 degrees. no bottom paint, salt water
37 mph @ 5400
41.4 mph @ 6000
STILL considering the powertech OSF4....

 

[SmokyMtnGrady]

Ky...just did another speed test myself this weekend.....'05 225 Tourney (same hull as yours, probably lighter though). 3-blade 15 1/2 x 17 SS (not in pristine condition) on original '05 F225.
Just me (210 lbs), 1/4 tank, 88 degrees. no bottom paint, salt water
37 mph @ 5400
41.4 mph @ 6000
STILL considering the powertech OSF4....

The OSF 4 will give you better cruise economy, better hole shot, it will hold better in tighter turns if you do water sports and it will give great following seas performance. It will also help with reverse too. You will lose about 1 mph on the top end. I had one on my boat until the motor got stollen.

 

[fathergoose]

My primary goal is to improve my cruising speed at a reasonable RPM. I would like to get 30 mph at around 4000 RPM. I think the performance spec shows 29 MPH at 3800 RPM. Right now I have to turn 4500 RPM to get 27 MPH. The speed is per GPS.

 

[DennisG01]

My primary goal is to improve my cruising speed at a reasonable RPM. I would like to get 30 mph at around 4000 RPM. I think the performance spec shows 29 MPH at 3800 RPM. Right now I have to turn 4500 RPM to get 27 MPH. The speed is per GPS.

As you probably know, those specs are done in ideal conditions with a light load (best case scenarios). But I think you're in the ballpark to make that happen based on the the perf spec and using the stock prop should work. HOWEVER, let's use the perf spec as an example to help talk about efficiency for a sec. That upper 3,000 range is typically where fuel usage (GPH) starts to spike. Meaning, wanting to see EXACTLY 30MPH and turning 4,000RPM will likely cost you at least a few GPH. Running at 29MPH or 28MPH, although only a mile or two per hour, will cut down your fuel usage quite a bit. In other words, just to see that "30MPH" on your speedo will cost you.

Have you checked the anti-vent plate?

 

[fathergoose]

As you probably know, those specs are done in ideal conditions with a light load (best case scenarios). But I think you're in the ballpark to make that happen based on the the perf spec and using the stock prop should work. HOWEVER, let's use the perf spec as an example to help talk about efficiency for a sec. That upper 3,000 range is typically where fuel usage (GPH) starts to spike. Meaning, wanting to see EXACTLY 30MPH and turning 4,000RPM will likely cost you at least a few GPH. Running at 29MPH or 28MPH, although only a mile or two per hour, will cut down your fuel usage quite a bit. In other words, just to see that "30MPH" on your speedo will cost you.

Have you checked the anti-vent plate?

I agree regarding the speed. 29 mph at 3800 would be great. As for the anti-vent plate, no I haven't checked that. What am my checking it for?

 

[DennisG01]

As for the anti-vent plate, no I haven't checked that. What am my checking it for?

See post #2, and others

 

[fathergoose]

I contacted my local dealer, who is very knowledgeable and willing to help with anything that he can, and he advised me to check the outboard bracket for water before I spend a bunch of money on a prop. He added that this probably is not be the whole problem since the WOT rpms are higher than he would expect, but it needs to be checked before trying a different prop. He also said that Yamaha props are still hard to get in a reasonable time and that I may want to look into a reconditioned prop from a prop shop if I wanted to stay with Yamaha. I checked and the bracket is bone dry, so I am looking at changing props. I originally was going to stay with the Yamaha prop but after reading the posts on here and hearing what my dealer had to say I am reconsidering. It seems that the powertech props are providing good performance and as far as I can tell they are available. Does anyone have any other brands that they have had success with?

Thanks for all of the helpful comments!

 

[Ky Grady]

Ken at Prop Gods would be my suggestion as a contact for the PowerTech props. He is a wealth of knowledge on props. Very happy with mine.

 

[jail]

You need to try a different prop. I had the stock SW2 15 1/2 x17 tuned for my Tournament 225. I was cruising 27 mph at 4700 rpm. I went to a new Powertech OFS4. I am now cruising 27 mph at 3700 rpm. At 4700 I am now going 36 mph.
Ken at Prop Gods said very few prop shops properly tune props for small craft.