Seafarer 226 with Yamaha 200 HPDI

[Bdsp1234]

Hey guys I am buying a 2001 seafarer 226 paired with a 2001 Yamaha 200 HPDI . I am concerned about wot and rpms. It will max at 5200 ( which technically is ok) and a wot of 32 MPH. It does have a stainless steel prop, but the size is not stamped on the prop.

I would think that I should get more RPM a and more top end.

Your thoughts.

 

[DennisG01]

Did you trim the engine up as far as it would allow? Explain your trimming procedure.

Check again on the prop - side, top, bottom - there should be something, somewhere that tells you what it is.

 

[Bdsp1234]

I trimmed the motor all the way down and then brought it back a few clicks, and then trimmed the tabs as much as I could before the boat got too high

 

[DennisG01]

From what you are saying, it sounds like you simply aren't running the boat properly for top end speed. You may consider hiring someone to show you how to do this.

Completely retract the tabs. Keep trimming up until speed no longer increases or the prop starts to ventilate. That will be your MAX RPM and Speed at WOT with the current load you have in the boat (which, for testing/comparing purposes should ideally be a light load, one person).

 

[Parthery]

I owned an '01 226 with a 200 HPDI. I ran it with a Mirage Plus 17 prop. Top speed was 42 at 5500 but you had to trim the engine waaaaay up. Otherwise, you would get 5100 and 39 mph.

It was a great boat....good luck with it.

 

[Bdsp1234]

I owned an '01 226 with a 200 HPDI. I ran it with a Mirage Plus 17 prop. Top speed was 42 at 5500 but you had to trim the engine waaaaay up. Otherwise, you would get 5100 and 39 mph.

It was a great boat....good luck with it.

Yeah. Somethings not right. At 5100 I only got 31. The current owner states the he never got more than 32 mph.
I called Grady white. They sent me an email showing the 2001 226 with 01 200 HPDI to be 29.7 at 4000 RPM without the hardtop.
It is the right prop. 13 3/4 x17.

 

[Bdsp1234]

From what you are saying, it sounds like you simply aren't running the boat properly for top end speed. You may consider hiring someone to show you how to do this.

Completely retract the tabs. Keep trimming up until speed no longer increases or the prop starts to ventilate. That will be your MAX RPM and Speed at WOT with the current load you have in the boat (which, for testing/comparing purposes should ideally be a light load, one person).

From what you are saying, it sounds like you simply aren't running the boat properly for top end speed. You may consider hiring someone to show you how to do this.

Completely retract the tabs. Keep trimming up until speed no longer increases or the prop starts to ventilate. That will be your MAX RPM and Speed at WOT with the current load you have in the boat (which, for testing/comparing purposes should ideally be a light load, one person).

I’ve owner 4 prior boats and know how to trim a boat.

 

[DennisG01]

I’ve owner 4 prior boats and know how to trim a boat.

I wouldn't have known that from what you wrote. All I can base my response on is what you've written and it was not clear. None of what you wrote indicates trimming it till ventilation or when speed no longer increases. For what it's worth, just owning boats doesn't mean someone knows how to properly trim for max speed.

I take it you found the prop specs?

If there's nothing wrong with the boat - damage or dirty bottom - and the prop is the proper one and in good shape - and the engine is in the proper hole - and the boat is being trimmed properly (still unsure)... the only thing left is an engine that's down on power.

 

[Parthery]

Where are you getting your speed readings from? The Yamaha speedo? If the pitot hole on the front of the gearcase has any crud in it, you won't get a true reading. On the other hand, if you are getting your readings from a GPS, then something isn't right.

 

[DennisG01]

If the pitot hole on the front of the gearcase has any crud in it, you won't get a true reading.

Good point.

Edit... Forgot to add... Although, even with a plugged pitot, he "should" still see the proper Max RPM's, I would think. Seems RPM's are low, as well, for that speed.

 

[Doc Stressor]

At 32 mph, I calculate that he is getting 31% prop slip running a 17" prop at 5200 rpm. Assuming his speed is correct and his HPDI 200 has the typical 1.81 gear ratio, that's way too much. A well set up Grady usually sees less than 20% slip.

That tells us the engine power is OK, but there is too much drag on the boat. Could be engine too low, bad bottom, or wet hull components.

 

[Parthery]

I didn't intrepret his 5100 to be WOT, but might be the case. Perhaps the OP can clarify that. Also, if he has a hardtop (?) and has the curtains up, you can create a mountain of wind resistance.....

 

[Bdsp1234]

Taking the boat out again tomorrow. Hull was tested with below 10% moisture in the hull anywhere. Compresion test done with 112-115 across. Motor is mounted at #2 hole as suggested by Grady White. The prop is correct. 13 3/4 x17 . Yes the boat does have a hardtop with a full enclosure. The prop certainly could use to be reconditioned. Yamaha asked if the prop is vented. Could be getting some slippage.

Doc stressor, you calculated exactly as I did at 70% . That seems poor. I’m going out with a certified Yamaha tech tomorrow to see what he says.

 

[Doc Stressor]

It doesn't take too much prop wear or damage to get a lot of slip when pushing a heavy boat.

Good luck tomorrow. The tech should be able to figure out your problem. Let us know the outcome.

 

[Bdsp1234]

Much better performance today. Replaced all the plugs. Number 5 plug was bad. Roled up the front curtains, cleaned trim tabs and prop. At WOT, got 5400 RPM and 37.8 mph, which works out to 79.4 % prop efficiency. Much much better than the 70% efficiency I was getting. I’m going to have the prop refinished or possibly consider a new vented prop.

Going forward with the purchase after today’s performance.

Thanks for the input

 

[Doc Stressor]

You should look into vented vs non-vented props on heavy hulls before you go ahead and get one. They are really for light boats that want a fast hole shot. You can pay a price in midrange performance, which is what's important for a 226. Call Ken at Prop Gods for a recommendation. 941-735-5808

 

[Bdsp1234]

You should look into vented vs non-vented props on heavy hulls before you go ahead and get one. They are really for light boats that want a fast hole shot. You can pay a price in midrange performance, which is what's important for a 226. Call Ken at Prop Gods for a recommendation. 941-735-5808

Doc, with those new numbers, are you in agreement that it’s worth moving forward with purchase ?

 

[Bdsp1234]

What prop size are you guys running? I keep seeing that you guys hit 40 plus. I was happy with the 5400 rpm, and that with two adult men. Was also satisfied with 38mph, but’s it’s not what you were getting.

 

[seasick]

I am late to this discussion but I wanted to check the math. The slip calculation may be off by 3% or so since I believe that the gear ration for the 200 HP HDPI is 1.86. The 1.81 ratio is for the 200hp EFI. The use of curtains during the measurement can greatly affect the numbers due to added drag.
The finding of a bad plug was also interesting. Of course that could lower WOT revs and top end speed , but I think it would lessen the slip. Am I missing something?

 

[Bdsp1234]

Seasick, you’re correct. 1.86 is the beta ratio on the 200 HPDI. After an actual calculation, I came up with 77.58 efficiency. My actual top end was 37.8 mph at 5400 RPM. I think I am now satisfied that the motor is good. It’s probably that the prop needs reconditioning to bring it all into line