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Old 07 June 2006, 11:39   #1
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A knee injury!

If you saw this on your boat and it had bubbling water coming through the crack what would you think?
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Old 07 June 2006, 11:42   #2
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I'd say give Andy Hightower a call, he'll give you Spartun Marine's number (the guys that recently re-did his transom) and prepare to part with wads of cash!

(And to think, ben wants to put bigger engines on it...)
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Old 07 June 2006, 11:51   #3
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If you saw this on your boat and it had bubbling water coming through the crack what would you think?
I'd think déjà vu... Advice: Structural Problems?
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Old 07 June 2006, 11:57   #4
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The crack is confined to the knees, not the width of the transom. Could it be that the gel coat has cracked and water has managed to seep into the wood structure under the glass. The boat was filled with water recently which could explain how the water got there.
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Old 07 June 2006, 12:02   #5
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Quote:
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(And to think, ben wants to put bigger engines on it...)
The engines I want to put on are the same weight, so I don't believe they will be more of an issue.
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Old 07 June 2006, 12:11   #6
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Could it be that the gel coat has cracked and water has managed to seep into the wood structure under the glass.
I can't think of any other explanation. You're always going to get water in the boat... rain, spray, so the fact that the boat recently filled with water is only one of many instances of when there will be water on the deck.

Ben - bear in mind that it's not just the static weight of the new engines that would be important - the pushing/twisting force on the transom (effectively pulling the top of the transom outwards) would be greater with any increase in power.
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Old 07 June 2006, 12:19   #7
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Have sent you a PM Gray.
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Old 07 June 2006, 16:38   #8
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Ben - bear in mind that it's not just the static weight of the new engines that would be important - the pushing/twisting force on the transom (effectively pulling the top of the transom outwards) would be greater with any increase in power.
Very true. But I think the knees get the most bashing when I go wave jumping and if anywhen, thats probably when the gelcoat on the knees cracked... Haveing 300hp instead of 230hp behind will of course make a difference, but have 400kg of engine bouncing around on the transom is the culprit this time I think
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Old 07 June 2006, 17:35   #9
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Very true. But I think the knees get the most bashing when I go wave jumping and if anywhen, thats probably when the gelcoat on the knees cracked... Haveing 300hp instead of 230hp behind will of course make a difference, but have 400kg of engine bouncing around on the transom is the culprit this time I think
But presumably you are planning this to get extra speed... ...does that mean it is likely you will be wave jumping more often and/or taking bigger jumps?
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Old 07 June 2006, 17:37   #10
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But presumably you are planning this to get extra speed... ...does that mean it is likely you will be wave jumping more often and/or taking bigger jumps?
I walked into that one!
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Old 07 June 2006, 19:35   #11
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Same thing happened to me last year. Gary at Spartan can help and does a very good job at a fair price. He ground the offending areas back to good glass screwed stainless studding though the transom and filled various large holes leftover from other engine installations. Structually everything was fine on my RIB but wanted it checked out all the same and water ingress long term is just as bad.

His Web page is: http://www.spartunmarineltd.co.uk/

My thread is: http://ribworld.com/forum/showthread...hlight=spartun
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Old 07 June 2006, 22:59   #12
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If you saw this on your boat and it had bubbling water coming through the crack what would you think?
Just a guess here since I don't know how your boat is built internally, sure looks like the boat is bending/ folding due to wave pressure, engine torque on the transom, the stiffest point tying the hull and the transom together is exhibiting signs of stress first, the cracking will probably continue.. Do you run it pretty hard? If you are going to put more power on it you probably need to reinforce the joint between the two ( hull and transom). With no gunwale supporting it there is a lot of stress. That being said, I hope it turns out to be less serious than my speculation makes it out to be, good luck!
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