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Old 08 May 2008, 14:40   #1
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Country: UK - N Ireland
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Boat name: JanJack /
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800rpm missing!!!

Well before we went down to view the boat we had a marine architect down to look at it and take it out for a spin. Everything seemed reasonably good... until they put it in the sea... 22knots at WOT and very slow acceleration - so slow it probably wouldn't get on the plane in the rough. He said it was also only getting 3200 rpm when it should be at about 4000.
The estimates for speed have all been over 30 knots at least.
How much of a speed difference will 800rpm on each engine make?
I'm guessing the props are too big so properly propping it should increase acceleration too?
Just incase you forgot it's an 8.5m redbay with twin steyr 144hp engines.

Thanks in Advance (again)

Conor
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Old 08 May 2008, 17:37   #2
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I'm guessing the props are too big so properly propping it should increase acceleration too?Conor
Since this is a second hand boat would the previous owner not have already been through getting the right props? It seems a bit odd to me, are you sure the engines are not knackered?
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Old 08 May 2008, 17:48   #3
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The owners seemed to not really know what they are doing.
What do you mean by knackered? The engines both have less than 200 hours on them.
The naval architect that looked at the boat also thought that someone might have changed some settings or electrical control for the engines - how would you find this out and reset it.

Regards

Conor
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Old 08 May 2008, 19:07   #4
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The owners seemed to not really know what they are doing.
What do you mean by knackered? The engines both have less than 200 hours on them.
The naval architect that looked at the boat also thought that someone might have changed some settings or electrical control for the engines - how would you find this out and reset it.

Conor
To be honest I have no idea why the engines may not be pulling full RPM I guess if it were me I would want this sorted before I parted with the money. Can't the owner confirm if the boat used to perform ok in which case the props are probably not at fault?
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Old 08 May 2008, 21:11   #5
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800rpm will make a big difference. If BOTH engines are acting the same it's unlikely to be any sort of normal fault. Either the props are totally wrong for the boat/engines or someone has meddled with things they shouldn't.

Find out what props they are if you can. Very slow acceleration could mean someone has tried to do what you want - fitted 5th gear type props to try to get a high top speed.

It could be a great way of getting a big drop in price................
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Old 09 May 2008, 02:51   #6
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Can you give me an idea of what would be a reasonable prop size for this boat and engines so I can compare it to what is fitted when I look at the boat on monday? Are there any sort of things I would be looking for that would tell me it's the props and not the engines or will the propellers be so big it will be straightforward?

Regards

Conor
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Old 09 May 2008, 03:05   #7
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Originally Posted by chorscroft View Post
Can you give me an idea of what would be a reasonable prop size for this boat and engines so I can compare it to what is fitted when I look at the boat on monday? Are there any sort of things I would be looking for that would tell me it's the props and not the engines or will the propellers be so big it will be straightforward?

Regards

Conor
Can't you talk to Redbay ref props they would fit,(read what is stamped on the props) and a local steyr engine dealer pay for them to check it over then offer less the costs if it's ok
When was it last serviced and who did it ask for a bill and go and talk to the people who serviced it

How many owners has it had ask for details of the last one and talk to them

Between the lines is this right rib for you,
reading the posts from day one it's not going to be fast enough
The owner seems to be vague to say the least are they hiding something, if it was all ok and I wanted to sell it I'd know how fast it went, WOT revs, what the switches were for on the console etc etc, the more you post on this boat the more I would steer clear it just does not feel good to me

my 2 pence worth

James
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Old 09 May 2008, 03:23   #8
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I will look at what is stamped on the props when I look at the boat on monday but, unfortunately there are no steyr dealers in Ireland.
It was last serviced 2 years ago and it hasn't been used since apart from test drives.
It has had 2 owners. The current owner received the boat as a part exchange for a mercedes and I'm fairly sure he doesn't have a clue about ribs or boats in general.
I still think it is a great boat if I can get the engine sorted. Although I would like to go faster as long as it can do 32 knots I'm happy enough - I just wanted to explore all the possibilities.
And as codprawn says, if it turns out it's only the props that are the problem I can use that to my advantage as a bargaining tool.

Regards

Conor
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Old 09 May 2008, 04:17   #9
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Conor, I would definately have a chat to Redbay once you know what size the props are. If the boat has only 200 hours and the props are not original they you might want to investigate further and find out why they needed changing, but as you say it's a bargining tool and wouldn't put me off the boat. Wrong props and a very slow speed might be the reason she was px'd and a little bit of work could soon have her sorted and running properly.

Nice trailer btw, if you do go ahead I have a brand new spare wheel that would fit her sat in my garage looking for a new home.

Pete
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Old 09 May 2008, 04:38   #10
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Mermaid

Might be worth speaking with Mermaid regarding the Steyrs. They are the UK agents.

http://www.mermaid-marine.co.uk/HTML/SteyrSummary.htm
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