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Old 08 November 2015, 08:51   #41
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I'm not sure the metal work does anything but distribute the load. I'd want to look at the hull join good and hard.

While 200HP is over rated, there are two issues with over rating - handling and hull stresses. I'd hazard a guess that 200 on that rib can be a challenge to control. Hull stresses - she hasn't fallen apart since then and presumably has had an MCA survey which is a start... Was it a 200 or 2 x 100... 2 x 100 is even heavier but stresses wise may be less...? 2 x 100 would be easier to handle and makes sense for the location.

On the other issue screwed down seats are not ideal but the console is also "screwed down". The CORRECT way to fit seats with self tappers is on a bed of sikka flex. If it is sikka then its doing the work not the tappers. The tappers just hold it there while the sikka cures. If someone used some kitchen sealer (white or clear would immediately ring alarm bells vs black) that is not doing the same as sikka flex. Well sealed on sikka water penetration may not be that big an issue. Although bolted down or glassed down would be better. Can glass down now, glassing over the tappers... OR bolted for that matter if you can get a nut and washer on the inside.
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Old 08 November 2015, 09:38   #42
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I'm not sure the metal work does anything but distribute the load. I'd want to look at the hull join good and hard.

While 200HP is over rated, there are two issues with over rating - handling and hull stresses. I'd hazard a guess that 200 on that rib can be a challenge to control. Hull stresses - she hasn't fallen apart since then and presumably has had an MCA survey which is a start... Was it a 200 or 2 x 100... 2 x 100 is even heavier but stresses wise may be less...? 2 x 100 would be easier to handle and makes sense for the location.

On the other issue screwed down seats are not ideal but the console is also "screwed down". The CORRECT way to fit seats with self tappers is on a bed of sikka flex. If it is sikka then its doing the work not the tappers. The tappers just hold it there while the sikka cures. If someone used some kitchen sealer (white or clear would immediately ring alarm bells vs black) that is not doing the same as sikka flex. Well sealed on sikka water penetration may not be that big an issue. Although bolted down or glassed down would be better. Can glass down now, glassing over the tappers... OR bolted for that matter if you can get a nut and washer on the inside.
The actual configuration of the previously proposed 200hp is not known to me at this time. If it was a single engine then the proposal was 70hp over the maximum recommendation by Humber. If it was a twin engine, then 90hp x 2 was the maximum recommendation. I have assumed that the manufacturer would know the design specifications, parameters and limitations of their boats better than a customer would.

The actual fixing method and quality is unknown by me at this time. Additional images will be sure to resolve that particular issue. Without any specialist knowledge and with no great general knowledge about boats, I have to be guided by what little I know, what others have advised and what my gut feeling is. The boat on offer MAY be perfectly serviceable and not give any great trouble to me as a new RIB owner. I am aware that buying into what feels to me like it could have been a less than well cared for boat, with hidden issues waiting to reveal themselves, is not a sensible course of action.

The nub of the issue for me is the willingness to override the manufacturer's recommended power maximum by altering the design from standard. Unless the owner was a qualified marine engineer, I don't have that much faith in the project as it was conceived. Everything else flows from that... I agree that if the seats were properly fixed, the issue would be negligible, other than if there was water present where it was not expected. I don't want a boat with a history of almost certainly bodged ownership behind it.

The facts speak for themselves... it is yellow, it quacks and waddles like a duck.
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Old 08 November 2015, 10:35   #43
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it sounds like you have made some progress as to whether to bother with this one.

i suspect this RIB used to be a dive boat and there used to be a rack behind that single seat. that would probably explain the huge engine on a small boat. with that much power on that size of boat it must have been capable of in excess of 60mph.......i wouldn't be on it!

the seats only being screwed down is pretty poor TBH given the extent of the refit done, fixable though if you are still of a mind to buy this one. as mentioned above, it is not uncommon to screw them down then glass over the screws internally. infact, some boats only screw them down with Sikaflex, it is strong stuff! however, if it is only sika'd to the deck flowcoat then that is the weak point perhaps. with that said, if i was doing that amount of a refurb and spending 4-5k on tubes, 9k ish on engine and maybe a grand in new seating i would glass them in for sure. just seems pointless to do it up to skimp a little on that part to me....but to each their own!

the age of the hull isn't really too much of a concern if it has been looked after TBH. Obviously only you can decide if it is a problem to you given what you know now.

one thing, the seller seems to have been remarkably honest with you and kudos to them for it.
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Old 08 November 2015, 11:12   #44
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That age of 5.8m destroyer was actually rated to 150HP, although it would have been based on 2 stroke weights.
Now a 150HP and a 200 HP 2 stroke weigh much the same.
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Old 08 November 2015, 12:52   #45
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Yes, thanks dubrus. I have noted that boat as a possible one on my list previously. I did do my powerboat 2 course with JBT and they have a dry stack facility too. Seemed like a helpful group of people to me. The 3 months warranty would be useful, if one could use the boat during that time.

I suspect that the worsening weather may play a part in limiting that usage from now on. I have a tiny insight concerning their particular stretch of the Solent after the powerboat 2 course. Boats at that end of my budget might restrict me when paying for a dry stack for the whole year. hmmm... I wonder what sort of discount one could achieve by not buying the trailer. I will give them a ring during the coming week. Of course the option to wait and squirrel away a few more squid is also a possibility.
Jello

If you do look at the ribquest make sure it's a Dave rose built boat as the previous owners had some build problems 2007 - 2008 will be ok that's the same boat as I have just sold same engine very good boat.

Cheers
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Old 08 November 2015, 13:59   #46
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That age of 5.8m destroyer was actually rated to 150HP, although it would have been based on 2 stroke weights.
Now a 150HP and a 200 HP 2 stroke weigh much the same.
I see. The weight is not the only issue with exceeding the recommended specification by some 25% if we take the 150hp figure. The power output and the resulting forces generated must play a part in the design of a sea-going vessel. I don't have any idea about what sort of safety margin the designers will build into their respective designs. I do know that when you a need some safety margin designed into any activity, the more you have then generally speaking, the safer you are in the event of a failure be it minor or catastrophic.

While I am reasonably sure that it would not mean instant death were a fitted engine to exceed the designer's intentions for maximum power output. The use of a machine beyond its tested design parameters may place the boat under strains and stresses that the designers have not specifically controlled.

It may well be that the boat concerned operates faultlessly for 999 times out of 1000. When the boat is stressed repeatedly in a manner which is uncontrolled by the design limitations, it will fail in unpredictable ways. I would not want any of my family or friends on that sort of boat. Keeping within the specifications may not actively save lives per se but it is unlikely to endanger them.

I am not trying to be censorious here. If a person wants to exceed the recommendations for the type of power plant they use, I don't particularly care. I would be happy to accept a ride aboard such a machine if it were just me deciding for me. I would not expose my family or friends to risks which they neither requested nor understand. I feel that usage specifications which are laid down by manufacturers of machinery are probably universally good guidelines to follow.
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Old 08 November 2015, 14:01   #47
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Jello

If you do look at the ribquest make sure it's a Dave rose built boat as the previous owners had some build problems 2007 - 2008 will be ok that's the same boat as I have just sold same engine very good boat.

Cheers
OK Jeff, thanks for the helpful information.
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Old 08 November 2015, 15:53   #48
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it sounds like you have made some progress as to whether to bother with this one.

i suspect this RIB used to be a dive boat and there used to be a rack behind that single seat. that would probably explain the huge engine on a small boat. with that much power on that size of boat it must have been capable of in excess of 60mph.......i wouldn't be on it!

the seats only being screwed down is pretty poor TBH given the extent of the refit done, fixable though if you are still of a mind to buy this one. as mentioned above, it is not uncommon to screw them down then glass over the screws internally. infact, some boats only screw them down with Sikaflex, it is strong stuff! however, if it is only sika'd to the deck flowcoat then that is the weak point perhaps. with that said, if i was doing that amount of a refurb and spending 4-5k on tubes, 9k ish on engine and maybe a grand in new seating i would glass them in for sure. just seems pointless to do it up to skimp a little on that part to me....but to each their own!

the age of the hull isn't really too much of a concern if it has been looked after TBH. Obviously only you can decide if it is a problem to you given what you know now.

one thing, the seller seems to have been remarkably honest with you and kudos to them for it.
Yes, I think this boat requires more attention than I could cope with given my meagre marine skills. The size of the engine and the sparse fittings before the addition of the later seating would suggest that you are right about the previous use. The phrase "spoiling the ship for a ha'porth of tar" comes to mind.

I suspect that only good pictures (hopefully in my possession soon) and being convinced by the RIBnet membership that it was not a poor purchase; are likely to sway me towards buying this boat. Thank you kindly for all of the good advice thus far.
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Old 10 November 2015, 18:57   #49
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pix of transom and seat inner

I have received two quite poor quality images of the seat inner and the transom inside. The seat shows a lot of screws and not much else. Their is no sealing in evidence as far as I can tell. I have requested an image of the outside fixing method for this additional seat.

My mark I eyeball detects that the screws are PZ roundhead screws with a variance of distance between and visibly different head angles. I suspect that pilot holes were not pre-drilled and screw centres were not measured and marked.

With the benefit of the larger image than can be posted I can also see cracked material round the 5th screw on the right (from the bottom up) and worryingly, there is a crack on its opposite number running along the material for a short distance. Approximately level with the two lower visible bolts is a line (tide mark/scum line) running around the inner container which appears as if the item was filled with water at some point. The dirt around the screw heads suggests that liquid may have been sloshing around in this compartment.

The transom image is only taken on the inside so detail and context are missing. I have requested another image of the outer aspect of the transom. I have no idea about the inherent strength of a transom but to my mind, the transom plate as fitted looks like a bodge.

With the benefit of the larger image, I can see each of the visible bolts (3 out of 4) is over torqued. There is a depression surrounding each washer and the metal is very clearly pushed in. Small washers and the use of too much force have contributed to this classic piece of butchery. The top right bolt hole appears to have been drilled in the wrong position as it is visible under the edge of the washer.

The top left bolt hole (under the red cable) appears to have the washer sunken into the metal plate. There is a distinct dark ring surrounding the washer that appears to be sunken to some degree. The other bolts exhibit this tendency to a lesser degree. The metal thickness is a detail I cannot comment on from this poor image. I suspect the main plate may be as thick as 14 gauge and it may well be some form of stainless steel. (aluminium would suffer from electrolysis in salt water)

The main plate disports a couple of subsidiary 'ears' which look to be about 16 or 18 gauge material. They support the jury rigged poles that are badly welded and held on with a couple of bolts penetrating the hull and secured with two Nylock type locking nuts. The poles extend to the hull superstructure (not sure what piece) and another piece of home brew fabrication. At the bottom of the main plate is a line showing a three small pits along its length which appear to have some sort of rust on them.

The quality which can be discerned from these two shaky images is not inspiring me to make the trip to Fife. I suspect that the enthusiast who modified the boat had abandoned the project because it could not work. I also suspect that the damage to the transom caused by using small diameter bolts and washers and then compressing two poorly welded bits of metal around the transom may have wrought far more damage than I want to take on at any price.

This boat
I will keep looking.

All comments are welcome.
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Old 10 November 2015, 19:58   #50
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Fairly serious transom work there. None of that should be there. Difficultly will be knowing what in under it of course.

The seats could be just moisture build up, happens all the time as usually something wet in storage, ropes etc.

I assume there is sikaflex under the seat, be silly not to. If you don't want to touch the outside of the seat they ideally should have cut out the inside, left a lip for screws and glassed inside to the bare deck. You could still do that of course at a later date.
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