NC 895 F300 prop

[lynnardm]

Hi fellow Merry Fisher and NC owners,

I've sold my 695 and have an NC895 ordered arriving in April. I have decided to go with a single Yamaha F300. I can't find much info on props.  Based on the limited data I can find on the 855 and 895, it appears that Jeanneau is under propping the boats with the F300.  In other words, putting on a prop with too small a diameter and/or too small a pitch.  I've come to the conclusion a Yamaha Saltwater Series II with a 15 3/4" dia and 15 pitch is the right choice, but can't find any test data with this prop installed on an 895.  Does anyone have info on props being used for the 855/985 with the Yamaha F300?  thanks

[lynnardm]

895 Offshore (US built) and Yamaha F300 Prop Testing

I wanted to share the results of my prop testing. I performed testing this past fall on my 895 and the Yamaha F300 with 4 different props.  Of note is that the initial tests were with the bare hull and later tests after hull bottom paint. And with some of the later tests there was more weight on the boat than I realized as the fuel gages were not reading correctly. Regardless the tests are good overall comparisons of the different props. And it looks like hull paint does knock a couple of MPH off the top speed regardless of prop.  

First I tested two Yamaha SS2 3 blade props. The 15” pitch 15 ¾” dia, 3 blade was slow getting on plane and had difficulty staying on plane at slow speeds. There was just too much slip at the lower speeds. But speeds above 25 MPH were great and even with a full load of fuel, water and gear for a week I reached 38 MPH. That’s before hull bottom paint. The Yamaha SS2 13” pitch 15 ¾” dia, 3 blade pitch was good getting on plane but also suffered staying on plane at lower speeds. I needed to be above 4800 RPM to stay on plane. This was the worst prop - it was geared way too low. In summary of the Yamaha props – for overall performance they were a disappointment. What I don’t understand is why none of the 895 and F300 tests out of Europe indicated these performance issues. It makes me wonder if the US Offshore boat is a lot heavier than the specification.
 
Next I tested two 4 blade props from Power Tech. The first was a 13” pitch 15 ¼” dia. This prop had a great hole shot but had more slip than I expected through much of the RPM range so was not a good solution. Finally I tested a Power Tech LSF4 16" dia x 14" pitch. Size (big dia) and number of blades do make a difference for a heavy boat! I really like this prop. It has good grip and feel at the lower speeds and gets the boat on plane quickly. It can plane comfortably under 20 MPH and has a slow comfortable plane at 3800-4000 RPM. It has good feel and good grip. I think it would perform well even in ocean swells. For WOT, it hit 5400 RPM at 33-34 MPH (after bottom paint).
 
The two best props were the Yamaha SS2 15.75 dia x 15" pitch 3 blade and the Power Tech LSF4 16” dia x 14” pitch 4 blade. Even though the LSF4 is 1" smaller pitch the LSF4 has more speed at a given RPM up to 4600 RPM where they are equal.  It has lower slip values at the low to mid speeds. The SS2 gains in speed above 4600 RPM as the slip values at higher speeds are about equal for both props and the SS2 has the larger pitch. Whats interesting is that both props turn about the same WOT RPM at 5400. At hull speed (6-8 MPH) and sub plane speeds its hard to measure but I expect that the LSF4 has better speed and MPG due to the grip of the increased blade area of the 4 blades. The LSF4 has better MPG at slow planning speeds. At mid planing speeds of 20-26 MPH both props have the same MPG. At speeds above 26 MPH the SS2 gives slightly better MPG, probably as the engine is not working as hard to spin 3 blades rather than 4.
 
In summary, the F300 has plenty of torque and power for even this heavy boat as long as fast cruising is not a mandate. The problem though is getting a propeller that hooks up at the lower speeds. Have I found the best overall prop for a NC 895 with the F300? For sub plane cruising (6-8 MPH) and slow to medium speed on-plane cruising I don't think the LSF4 can be beat. But if one wanted to regularly cruise at higher speeds (30 + MPH) the prop that might be worth testing is the Power Tech three blade LSF3 16" dia x 14" pitch. In considering it relative to the Yamaha SS2 15” pitch and Power Tech LSF4 14” pitch... I'd expect it to have slightly less grip at slow speeds and slightly slower time to plane than the LSF4, but better than the SS2. I'd expect it to reach higher RPM than both these props, around 5600-5700, thereby resulting in a higher top speed probably equal to theSS2. And I'd expected it to get better MPG than the LSF4 at 26 MPH and faster. I wanted to test this prop but didn’t as I was pleased with the LSF4.

Capt,n

Lynn

[Skipper Bogo]

Hi to everyone!
I'm new on Jeanneau Owners Forum and I welcome you from Slovenia. Since I also intend to buy NC895, or as we call it in Europe, Merry Fisher 895, I am very interested in your conversation about a suitable propeller.
I have a question for Capt Iynn: on which hight (hole) is your engine mounted? 
Now I own the Jeanneau Cap Camarat 5.5 WA Series 2 and at the time I bought it, the motor was mounted too low (on the 2nd hole), ventilation plate was 1" above boat bottom, so that I could not trim the engine high enough, that the ventilation plate could be above the water level. I gradually lift it up to the top (to 4th hole). Now the ventilation plate is 2.5" above the boat bottom and I can trim the motor just as I wanted. The speed difference was obvious and I got 100 - 150 RPM at the WOT (earlier 5400, then 5500).
I write this because I noticed that the dealer usually mounts the engine too low, which has a strong impact on drag and consequently on max. RPM and top speed. 
So I'm curious, on which hole you have your engine mounted and how hight is ventilation plate above boat bottom? On Yamaha Performance Bulletin is tested Ranger Tugs R-27 with Yamaha F300, mounted on the 4th hole, with a ventilation plate 3.5" above the boat bottom.

Greetings,
Bogdan Vrezner

[lynnardm]

Bogdan

Welcome to the forum. My f300 is mounted using the 2nd hole from the top. There are 4 holes for height adjustment on the engine. This places the cavitation plate right in line with the bottom of the keel (the bottom of the hull). The engine was mounted locally in Seattle by the dealer. The technician thought that the cavitation plate at this location was desired and confirmed this was the recommended location including the hole pattern with jeanneau. I can trim the engine up several indications (the trim indicator lights on the Yamaha gage) while going straight on plane before getting evidence of any ventilation. In a hard turn on plane I need to trim the motor full down to prevent ventilation. So based on these performance items I believe the height is correct.

Thanks
Capt’n Lynn

[Skipper Bogo]

Hello again!

Thanks for the reply. As I understand from the written, the engine is mounted on the 2nd hole from the top, where the anti-ventilation plate is aligned with the bottom of the boat hull. In my case, the seller also recommended that the engine should be on the 2nd hole, but later I found that the boat behaves better with a slightly higher installed engine and the fuel economy is better too. Regarding on hard on plane, as I heard, it is always advisable to trim the engine down before turning.

So I am interested in following: is the anti-ventilation plate above the water surface when the boat is on plane? As I heard from the advice of other boat owners, it should be so. And, in your opinion, would the raising the engine for one hole reduce drag and consequently increase the RPM of the engine? The theory says that for every 1" engine raising (at higher speeds), we can get an additional 1 mph. In your case, at a lower speed, of course less, but still up to extra 100 RPM.
If the anti-ventilation plate is already above the water surface when on plane, this is, of course, irrelevant.

Regards,
Bogdan

[lynnardm]

Bogdan

You stated you found out the boat behaves better and gets better MPH with the engine mounted higher. Can you provide any more details about this and is this referring to the 895 and F300? Doing a visual Check of the anti-ventilation plate to see if it’s under orr above the water Is a good idea. Next trip I’ll have a look and report back. Are you about to take delivery of a new boat?

Capt’n Lynn

[Skipper Bogo]

Hello Capt’n Lynn!

As I mentioned in my first article on the forum, I own the Cap Camarat 5.5 WA Series 2 and at the time I bought it, the motor was mounted too low (on the 2^nd hole), anti-ventilation plate was about 1" above boat bottom. I could't trim the engine that high (without pumping the bow up and down) to get the anti-ventilation plate above the water level. So I gradually (the spacing between the holes is 0.75") lift the engine up to the top (to 4^th hole). The reason for all this was the purchase of a new SS propeller last year (Talon SS SDS 13 1/4 x 18", before Alu 13 x 19").  As I didn't consider the recommended reduction for 1 - 2" in pitch from Alu to SS), to big selected pitch causes me not to reach enough RPM at WOT. 

After raising the engine the anti-ventilation plate is good 2.5" above the boat bottom and now I can trim the motor just as I want. When on plane at about 25 - 30 kn the anti-ventilation plate is about 3/8" above the water level. The speed difference was obvious (before 35 kn, after 37 kn) and I've got additional 100 - 150 RPM at WOT (before 5400, after 5500). The fuel economy is a bit better too. 

Of course, there is no direct comparison between my CC 5.5WA and MF895, since the MF895 is a much larger and heavier boat, but a basic rule applies to both boats. The main difference, as a result of the greater weight, is in the slip of the propeller. At my CC5.5WA it is only about 3 - 4%, and more than 13 % at the MF895.

I haven't ordered MF 895 yet. During the boat show in Cannes (France), I can get bigger discounts, so I will wait until the summer. I hope that next spring I will be on the water with a new boat! However, I'm already collecting the necessary information on the relevant engine (already decided: Yamaha F300B) and the rest of what I need when ordering the vessel.

Greetings,

Bogdan

[lynnardm]

Bogdan

I finally got out on the water to take a look at the position of the ant-ventilation plate.  The first picture shows the drive out of the water.  I marked a stick with 1" increments.   For reference, the anti-ventilation plate is about 2.5" below the other smaller fin/plate (not sure what that's called).  The 2nd pic is with the boat up on plane going about 25 MPH.  The trim tabs are full down, and the engine trim is set at 3 bars up (from full down).  The smaller fin/plate is definitely out of the water.  But I can't see the anti-ventilation plate as there is so much spray and water movement.  So I can't positively determine the location of the anti-ventilation plate, but it appears like its in the water.  I was hoping to be able to put the stick on it to get a feel of its location but the water/spray is too violent and the force of the water just pushes it away.   You may recall that I mentioned earlier that if I move the engine trim up a couple of bars from this position I start to get ventilation so I know that the propeller and hence the anti-ventilation plate is pretty close to the surface.  If you learn anything or get additional info on the optimal height for the 895 & F300 please let me know.

www.23hq.com/lynnardm/photo/52312979/original


www.23hq.com/lynnardm/photo/52312984/original

thanks

Capt'n Lynn

[lynnardm]

I just talked with Yamaha tech services. They say the engine should be mounted with the anti-ventilation plate at the bottom of the hull or up to 1” below the bottom of the hull. The plate is designed to be run submerged while the boat is on plane. So per Yamaha the height as installed on my 895 (at the bottom) should be correct.

Capt’n Lynn

[Skipper Bogo]

Hello again, Capt. Lynn!
A few days ago, I finally got my boat Merry Fisher 895 with Yamaha F300, but I'm not satisfied with the behavior of the vessel.
I was surprised by the high consumption at and above planing speed. To make the boat on plane, I have to run it at 4800 RPM or more. Propeller is from Yamaha SW 15 3/4 "x 15", the engine reaches good 5500 RPM at WOT. I mounted motor higher than is yours (cavitation plate is about 0.8 - 1.0” abowe botom). Even in sharp turns, without tilt down, the propellers did’t get air, so I think it is not too hight.
I would be grateful for some information about your fuel consumption and/or MPG at various speed and RPM required in the area when the boat starts get on plane (betwen 18 and 25 Knots). I know that you have a different propeller, but you probably have some old information about the behavior of the Yamama SW Propeller boat from your propeller testing.

Regards,
Bogdan

[lynnardm]

Bogdan

I should still have the excel spreadsheet where I compiled the prop data. Send me a private message via this forum with your email and I’ll send you a copy along with my phone no I’m case we
Decide to chat. From
What you describe it sounds like you are having a similar experience with the Yamaha propeller. In my case the propeller could not get enough grip at the lower speeds. The resulting high slip resulted in poor overall performance for feel/response, speed to plane, and fuel consumption at the lower speeds.

Capt’n Lynn