carver 320 1992 speed poor

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Robert
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Vessel Info: Carver 320 1992 twin volvo penta tam31
Location: North uist Western isles

carver 320 1992 speed poor

Post by Robert »

Hi all I have carver 320 1992 with two Volvo Penta tamd31 I get full revs under load 3900 rpm
gearbox ratio is 1.93 prop size 18x15 can only get 10 nots no vibrations everything runs sweet
top speed not good :help:
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Rocketman
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Re: carver 320 1992 speed poor

Post by Rocketman »

Bottom Paint.
Your hull is fouled to the point that it is causing too much drag.

My first indication is always that my speed/fuel economy starts dropping.
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bud37
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Re: carver 320 1992 speed poor

Post by bud37 »

Robert wrote:QR_BBPOST Hi all I have carver 320 1992 with two Volvo Penta tamd31 I get full revs under load 3900 rpm
gearbox ratio is 1.93 prop size 18x15 can only get 10 nots no vibrations everything runs sweet
top speed not good :help:
Welcome to the forum.....is this boat new to you or is this just a recent thing getting worse ?
FWIW.....The above is just my opinion.
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buster53
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Re: carver 320 1992 speed poor

Post by buster53 »

Rocketman wrote:QR_BBPOST Bottom Paint.
Your hull is fouled to the point that it is causing too much drag.

My first indication is always that my speed/fuel economy starts dropping.
I agree that a fouled bottom is most likely, but if the running gear was fouled, no way the engines would hit full operating RPM’s.
Yes, we need more info.
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