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beachbum_ln

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"Help I think this boat is cur

"Help I think this boat is cursed. 1987 Bayliner 2750 and all I can get is 22 mph at 3,000 rpm. Prop is a 15 x 15 the carb has been rebuilt new float, all filters including water filter replaced, new check valve and gas tank filter. All new plugs, coil, wires, points etc late last year (maybe 30 hrs total) Will be replacing the interupter switch shortly. Another point is it still wants to bog down for a second or two when accelerating. What else can I do ?????????"
 
"Jim, I feel your pain! I had

"Jim, I feel your pain! I had a 85 Bayliner 28 footer with a similar problem--and it had a fresh Marine Power Vortec 315 hp. engine in it. It would cruise all day at 3,500 rpms, doing about 25 mph, while swinging a 15 x 19 prop and burning about 12 GPH, but it absolutely would not go above 29 mph. Nor would it rev over about 4,200 rpms. Weird.

Contacted other Bayliner owners on the comany web site, and many have the same result. The apparent asnwer is this: That hull was not designed for speed. Period. (It runs great in rough water, though.) At speeds above 26 mph or so the hydrodynamic drag rises so quickly you'd need a 8.2 liter race motor to get it pass 35 mph!
(A guy across the river dropped a 454 in his, and it went one freakin' mph faster!)

Here's what I recommend you do: Beg, borrow or buy a 15 x 19 prop (that's right, 19 pitch). Mine ran best with that prop, and I tried props down to 17 pitch (which was horrible).

Jeff

PS: Mine had a V-P drive, single prop. The Cobra might have a different gear ratio, so adjust accordingly."
 
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