Sunseeker Cobra 39 sluggish

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09-24-2018 | 06:49 PM

#21

Rookie

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From: Grand Rapids, MI

Quote:

Originally Posted by CobraGuy

Question: In the combination with 10-20% barnicles(the small shells) on the hull, could this affect the performance this much?

Yes, it can affect it a lot. Clean the hull. Does the hull have bottom paint also?

09-24-2018 | 06:58 PM

#22

CobraGuy

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Thanks, it’s on land now and cleaned. It has bottom paint. Each lift in/out in the sea cost like 1500$ so I like to be as sure as possible when I dump it in again. But I will try again, hull cleaned and see what happens.

09-24-2018 | 07:07 PM

#23

compedgemarine

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From: Murrayville Georgia

cleaning the bottom may make a big difference but if it is not enough the first question is do you know what the ratio in the drives are? with that info we can figure out what the slip is and what it should run. also did you ever ride in the boat with the previous owner and really see it run those numbers? not to say it did not run that with this setup but it would not be the first a seller embellished the performance numbers.

09-24-2018 | 07:12 PM

#24

underpsi68

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I find it odd if it was slip that both engines are slipping the same? Both couplers are slipping the same? The slip isn't getting worse?

Sorry just trying to help.

It seems like both engines are turning 4500rpms. How are the props?

09-24-2018 | 07:22 PM

#25

Boomer35

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From: Jacksonville FL

Your add says “0 hours on drives”. Did the gears change in these new drives?

09-24-2018 | 07:32 PM

#26

CobraGuy

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Quote:

Originally Posted by Boomer35

Your add says “0 hours on drives”. Did the gears change in these new drives?

The engines and drives was renovated by some marine mechanic. Is it possible gears could be wrong, it sure acts like it.

09-24-2018 | 07:35 PM

#27

CobraGuy

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Quote:

Originally Posted by underpsi68

Don’t be sorry, I appriciate all the help I can get. All out of ideas... I don’t think they slip because the speed sucks all they way from neutral to wot. Props look like new, maybe some super light corrosion.

09-24-2018 | 07:40 PM

#28

CobraGuy

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Quote:

Originally Posted by compedgemarine

Do not know gearing but would say original.
Have not seen it in action but I don’t really care if it runs perfect at this point but it feels very weird that we can’t make this boat plane with this kind of power. A known car tuner looked at the cam sheets and the other parts and said the build looked good and should deliver way over 400