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YAMAHA OX66 225 Propeller Question

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YAMAHA OX66 225 Propeller Question

Postby Guitar1 » Jun Mon 28, 2010 11:05 pm

Hello Gentlemen,

I purchased a 1998 Grady White 209 Escape with a blown 1998 Yamaha OX66 225 engine.
With the engine completely rebuilt by a very reputable Yamaha dealer, my boat still only reaches 5200 RPM wot. The prop is a Stainless Yamaha 15 1/4 X 19. I believe that propeller was a factor in the "short" (350 hrs) engine life. My research indicates that the correct prop should be a 17.
Does anyone out there have a 209 Escape with a 2 stroke 225 who could tell me what prop you are running.
Grady White is unable to get the archived performance bulletin for that boat/motor combination.
Any help in getting the correct prop for the correct wot RPM would be most appreciated.

1998 Grady White 209 Escape
1998 Yamaha OX66 225 HP 2 stroke engine

Thanks again!

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Joined: Dec Thu 03, 2009 2:16 am

Postby 3rd Day » Jun Tue 29, 2010 12:33 am

Yes Sir, I believe you are correct. I ran a 250 on a similar boat and the prop was a 17. WOT was 5500. Give it a try. PS, you'll enjoy the hole shot.
93' 232GT Gulfstream 150 Yam X2 "3rd Day" Gen. chap. 1 vs. 9-13
3rd Day
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Location: Charleston SC

Postby Parthery » Jun Tue 29, 2010 2:03 am

Running that motor at 5200 WOT is still within the recommended range and likely didn't contribute to its initial demise.

That said, I'd look for a 17" wheel...should be a perfect fit.

2000 GW 225 Tournament / 225 OX66
GreatGrady Captain
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Location: Atlanta, GA

Postby Gradylure » Jul Thu 01, 2010 2:21 pm

One other thing would be to check 02 sensor. They get dirty with oil if motor running rich. This can effect your rpms and full throttle.

Hope you mechanic fixed the problem that cause the powerhead to pop. I had twin 250 ox66 motors on my last boat, and the ran great but were thirsty, and needed lots of attention. O2 sensors, vst filters, ring free.

If you follow do the pm's you should get many years from them.

Enjoy the new rig
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Joined: Mar Wed 24, 2010 1:21 pm
Location: Mount Pleasant SC

Postby uncljohn » Jul Thu 01, 2010 4:30 pm

my 228 runs about 5200 WOT w/ a 200 OX66. I normally cruise at 3800-4200 rpms.

The manual will say WOT should be 5000-6000 rpms. So I think you're ok.

If anything, it wasn't the prop that blew the engine, it was running it WOT!!!
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