Need prop size for 2850 Bayliner

[Rick Rickerson]

I have a beautiful 1987 2850 Bayliner command bridge with a single 7.5 (460 Ford) OMC. My prop was lost "don't ask". I can't remember what size it was. I can only reach 3000 rpm's with the new prop which is 15.5 X 15. I should reach 4400 to 4800 . The engine runs great and I have checked throttle linkage. The boat is heavy with a generator. Any help would be greatly appreciated. Thanks, Rick.

 

[Bart Sr.]

Re: Need prop size for 2850 Bayliner

RICK Sorry I can't help with the prop. I was surprised to see that someone from MY HOME TOWN was posting in this forum. My family name is KILGO. I am almost 30 years transplanted to MINNESOTA but most of the siblings are still in GRIFFIN. You will be happy with the results on this site!!!!!!!! THANKFULLY AND RESPECTFULLY BART (LANDLOCKED) SR.

 

[Bart Sr.]

Re: Need prop size for 2850 Bayliner

RICK Check the posting in this forum NOT SURE ABOUT PROP SIZE BIGBABYLOU and check out the link for prop sizing there. Hope it helps. THANKFULLY AND RESPECTFULLY BART (SEVERELY LANDLOCKED) SR.

 

[DJ]

Re: Need prop size for 2850 Bayliner

Rick,<br /><br />Typically, you can figure one inch of pitch in the prop. is good for about 200 rpm.<br /><br />Using that logic, you're going to need a 7" pitch prop to get to 4400 rpm. Something doesn't compute here.<br /><br />Are you SURE the prop you are running is a 15" pitch?<br /><br />The 460/King Cobra is a strong set up. What brand of prop. is the one you have on now?

 

[gregorysmit]

Re: Need prop size for 2850 Bayliner

I had the same boat, also heavy with generator, and a 17.75 X 19 gave me the desired performed. Cruised at about 19-19 knots. Topped at about 26.<br /><br />Greg

 

[Mufasa]

Re: Need prop size for 2850 Bayliner

I agree, something else has changed here. Take another look at that prop size. The 15*15 should wind up nice and keep the rpms up higher than you are reading. The math does not work out.