New to me 2009 Tournament (Freedom) with single F350. Boat has approximately 180 gallons fuel, bottom paint and hardtop. Full throttle with me alone getting 5800 RPM and 44.5 MPH with a enertia eco 17" prop and 5 bars trim on the command link gauge. Pulling back to 4,000 rpm, boat will slow to the point of bow-high plowing (no tab). 3/4 tab will keep boat on plane at lower rpm and all is fine. Engine mounted in 3rd hole from top. First grady I've owned, wasn't expecting to have to use this much tab at lower rpm, is this normal?
275 Tournament falls off plane below 4,000 RPM?
- Thread starter lyncha00
- Start date
After talking with Ken and looking at the AV plate I'm going to raise the engine up a hole. Anyone with a single F350 on a 275 ever try this? The top mounting hole would move form the 3rd to the 4th hole from top. I'm also going to try a Powertech LFS4 to see how it does vs. the Eco.
If the existing prop isn't what grady had on it from the factory, I would change it back. If the prop is original as delivered by grady and if it was ever reworked, I would get it checked to make sure it is close to spec.
The lfs4 will accomplish nothing but worse mpg and a listing condition unless you can get the AV plate at or slightly above the water. Ask me how I know. :mrgreen:
The lfs4 will accomplish nothing but worse mpg and a listing condition unless you can get the AV plate at or slightly above the water. Ask me how I know. :mrgreen:
350 YAMAHA FOUR-STROKE Single
Engine Size:
5.3L
Test Date:
4/26/2007
Prop Size*:
16 1/4 X 17 SWS XL SDS
Weight as Tested:
7799 lb. (including persons, fuel, water, gear, engines & accessories)
Hardtop:
No
Bow Pulpit:
No
Bottom Paint:
No
Optimum Cruise: 29.2 MPH @ 3700 RPM
Top Recommended RPM: 5000 - 6000
RPM MPH GPH MPG
1000 5.3 1.4 3.79
1500 7.6 2.6 2.98
2000 8.9 4.5 1.99
2500 13.1 6.6 1.99
3000 19.5 9.1 2.15
3500 26.6 11.2 2.39
3700 29.2 12.4 2.36
4000 31.9 14.0 2.29
4500 36.9 18.0 2.05
5000 41.4 22.9 1.81
5500 46.2 30.4 1.52
6000 49.1 33.8 1.45
Engine Size:
5.3L
Test Date:
4/26/2007
Prop Size*:
16 1/4 X 17 SWS XL SDS
Weight as Tested:
7799 lb. (including persons, fuel, water, gear, engines & accessories)
Hardtop:
No
Bow Pulpit:
No
Bottom Paint:
No
Optimum Cruise: 29.2 MPH @ 3700 RPM
Top Recommended RPM: 5000 - 6000
RPM MPH GPH MPG
1000 5.3 1.4 3.79
1500 7.6 2.6 2.98
2000 8.9 4.5 1.99
2500 13.1 6.6 1.99
3000 19.5 9.1 2.15
3500 26.6 11.2 2.39
3700 29.2 12.4 2.36
4000 31.9 14.0 2.29
4500 36.9 18.0 2.05
5000 41.4 22.9 1.81
5500 46.2 30.4 1.52
6000 49.1 33.8 1.45
Have tried tried trimming the engine back down some as you pull back on the throttle? Or are you keeping it trimmed up? Your top speed isn't that far off from the numbers that are posted above. It could be that they were testing with a half tank of fuel, while I assume your 180 is close to full? They also likely did not test with bottom paint. Is your bottom paint in good, smooth condition? If it's thick/cracked (or has been sitting for a while and has a slime layer), that can be causing extra drag. Prop is in very good shape? Also, where you run the boat can have effect on speed, too. I would cross off all these items before making any changes.
I sea trialed the boat with the original prop (same as in the yamaha test, SWS XL 19"), and saw 42 MPH at 6100 rpm compared to the 44.5 at 5800 with the eco. The original prop was not in great shape with some dings and scratches which, combined with the low top end, is what prompted the switch. I wish I had tested it more carefully on the sea trial at 3500 or 4000 rpm but I didn't. I've used mercury props on my last boat with better results over the stock yamaha prop which is I why I went with the eco for this but who knows, I may end up back with the factory prop, though new, which is why I like working with Ken. 
DennisG01 - My boat has a hardtop, fresh bottom paint (the Yamaha test bulletin has neither) and about 80 gallons more fuel than in the test which could explain a good amount of the top end discrepancy but I would have to imagine that if I could get the same rpm out of the eco (which is brand new), I would be close to the test bulletin rpm. I have tried trimming down at lower rpms and it doesn't help, only heavy tab keeps it on plane.
My primary goal is the best performance between 4000-4500 rpm which, combined with the planing issue, has been why I've been leaning towards the 4 blade. I don't expect raising the engine height to do a whole lot but if it reduces some drag with no other side effects than great. Honestly, I think the eco has really good bow lift which is not exactly what I need.
Family Affair - which boat did you try the lfs4 on and at what pitch? I do have considerable prop torque list with the eco but it mostly goes away once I trim the motor up.
DennisG01 - My boat has a hardtop, fresh bottom paint (the Yamaha test bulletin has neither) and about 80 gallons more fuel than in the test which could explain a good amount of the top end discrepancy but I would have to imagine that if I could get the same rpm out of the eco (which is brand new), I would be close to the test bulletin rpm. I have tried trimming down at lower rpms and it doesn't help, only heavy tab keeps it on plane.
My primary goal is the best performance between 4000-4500 rpm which, combined with the planing issue, has been why I've been leaning towards the 4 blade. I don't expect raising the engine height to do a whole lot but if it reduces some drag with no other side effects than great. Honestly, I think the eco has really good bow lift which is not exactly what I need.
Family Affair - which boat did you try the lfs4 on and at what pitch? I do have considerable prop torque list with the eco but it mostly goes away once I trim the motor up.
The test by Grady shows a 16.25" prop, but you said the boat came with a 19? Are you sure you started out with the recommended prop?
We actually tried the ofs4 on the Voyager, but regardless your results will be similar if you can't get the prop high enough. 15.25" x 16 pitch.
We actually tried the ofs4 on the Voyager, but regardless your results will be similar if you can't get the prop high enough. 15.25" x 16 pitch.
Yes, I'm sure and yes, it is confusing! The SWS XL in the April 2007 yamaha bulletin test is 16.25" in diameter and 19" pitch. That is what you will see in the pdf on the Yamaha site performance archive. The grady site shows the prop as 16.25" diameter 17" pitch SDS for the same April 2007 test because when they went to the SDS hub they relabeled the pitches and the old 19 became 17. As the SDS is the newer style, GW replaced the 19" non SDS from the original test with the new equivalent on their website.
This prop may still end up being the best fit, will have to test.
This prop may still end up being the best fit, will have to test.
You mentioned you had looked at the AV plate and thought it needing raising. I would definitely do that before you start doing anything else. You never really know till you try, but there is a good chance it can help your situation.
You're not carrying an excessive amount of weight at the stern, are you? Does the bilge have water in it?
You're not carrying an excessive amount of weight at the stern, are you? Does the bilge have water in it?
The bilge is dry as a bone, and the livewell and fish box are empty so not a lot of extra weight in the back. I will be moving the engine up a hole this week.
Punch53 said:
Not sure if 5bars is a lot or not, could mean my engine can be mounted higher but I think its hard to compare bars across models and engine types.
So my Powertech LFS4 came before I could move the engine up and I tried it out. Incredible difference, now stays on plane down to 3300 rpm with no tab whatsoever and better MPG up to ~4400 rpm. Above that, the extra blade takes a toll, went from 44.5 with the Eco to 40 with the LFS4. As I care more about the midrange I will keep this one on and raise the motor up later in the season.
Sorry for the delay, worked out fine with the reconditioned OEM prop but top speed with bottom paint and half load is only 41 mph. With a F350C I would think a few more mph than the F350A I'm running.
I ended up buying the one I was looking at, a 2011 with an F350A and a Yamaha prop. I get 44 MPH with a full tank of gas and two passengers, no bottom paint, and a tailwind. However that also burns 31 GPH so I'm cruising at 30 MPH where the burn is more like 16 GPH.
I see about the same cruise/gph. I had a prop shop add some cup which gave me a little better performance at cruise. Overall I've been happy with it, I just updated all the electronics this summer, 60+ hours so far this season.