Sea Ray Sundancer 290 Re-Power Options

thesaintlyone

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I bought a 1992 Sea Ray 290 Sundancer in great condition both inside and out for £5000 because the twin engines were knackered and and had been removed.

I have three options as far as re-powering goes:

Option One: Re-Power with Like for Like Twin V6's and Stern drives which is financially not viable

Option Two: As I previously Discussed an Outboard Conversion. I have been quoted for a muts nuts conversion that's would look like it should be that there not just some bolt crappy frame on the back £3500 plus the cost of two outboards which I have seen for £1600 each

Option Three: Given that the same boat was fitted with a single 300hp 7.4L Mercruiser as an alternative to the twin V6's. Glass Over the existing transom holes and cut a single hole and build new engine supports and install a 300hp Single Engine £5000 plus glass work


I would like your thoughts on those and also here are some questions to help me decide.

1) Given that I have a single leg would I need to match that to an engine thus making my engine choices more limited or adding the expense of a new leg

2) Do say 2x 150hp outboards produce the same performance as a single 300hp inboard and alternatively if I went for a 300hp diesel inboard as opposed to a 7.4l petrol 300hp inboard will the performance be affected

Regards ?
 
I would like your thoughts on those and also here are some questions to help me decide.

1) Given that I have a single leg would I need to match that to an engine thus making my engine choices more limited or adding the expense of a new leg

2) Do say 2x 150hp outboards produce the same performance as a single 300hp inboard and alternatively if I went for a 300hp diesel inboard as opposed to a 7.4l petrol 300hp inboard will the performance be affected

Regards ��

1) new leg almost definitely but check the leg's hp / torque ratings just to be sure.
2a) 2 x 150 does not equal 300. I would be guessing but probably more like 250. I'll take a Mulligan on that one. It's complex
2b) a 300Hp diesel is significantly heavier. Whether it will have an affect on handling I suppose comes down to is it heavier than what is already in. For performance I would go petrol, for price I'd go petrol. Personally I hate petrol but in this instance I'd think you'd be barking to re-engine with diesel.
 
The best option would be Option 1 - like for like.
Is that still not viable if you managed to find used / refurbed engines and drives?

Next most preferable Option would be the single engined conversion with "just one big one".

The Outboard option is madness, imho.
That hull wasn't designed for outboards, and you have no idea what the trim or handling like will be with the weight of the engines hanging off the back.
 
I bought a 1992 Sea Ray 290 Sundancer in great condition both inside and out for £5000 because the twin engines were knackered and and had been removed.

I have three options as far as re-powering goes:

Option One: Re-Power with Like for Like Twin V6's and Stern drives which is financially not viable

Option Two: As I previously Discussed an Outboard Conversion. I have been quoted for a muts nuts conversion that's would look like it should be that there not just some bolt crappy frame on the back £3500 plus the cost of two outboards which I have seen for £1600 each

Option Three: Given that the same boat was fitted with a single 300hp 7.4L Mercruiser as an alternative to the twin V6's. Glass Over the existing transom holes and cut a single hole and build new engine supports and install a 300hp Single Engine £5000 plus glass work


I would like your thoughts on those and also here are some questions to help me decide.

1) Given that I have a single leg would I need to match that to an engine thus making my engine choices more limited or adding the expense of a new leg

2) Do say 2x 150hp outboards produce the same performance as a single 300hp inboard and alternatively if I went for a 300hp diesel inboard as opposed to a 7.4l petrol 300hp inboard will the performance be affected

Regards

I had a look back at your last posts and there was a reference to paying silly money for the boat.

£5k for a aged boat with no engines seems like a lot of money.

On line there is a 1996 for £17k, so it can be bought for ..... less than that ( old petrol powered boats are not that popular).

Your option 2 which is not optimal and will as per other posts make it even harder to sell is £7k before all the other bits you need to buy ( steering? Instrumentation? numerous odds and sods). I dont know the cost of option 1, but option 2 does not really seem great. The boat will stand you in at some £13-14k for a boat with i assume second hand outboards that should not have outboards in the first place ...

The options to me would seem

1. try to sell it

2. Option 3 ( if it is financially viable) as at least it will have an engine configuration that it was supplied with so there is some chance of selling it. On a personal level I would not buy a boat modified from 2 to 1 engines, but others may differ.

If considering this you should find out if there are other modifications when there was one engine. I am thinking different tabs, placement of batteries / water tanks to allow for I would assume quite a different weight distribution.

Also bear in mind that the instrumentation, throttles etc will also need modification which will be more time and cost.

Many come along to this forum looking to repower boats. I believe I the universal view is dont do it. I dont know how many of those have gone on to actually do it.

Good luck
 
Thanks Bruce I'm looking at the single Engine option as the same boat was sold with either twin or single Engine Conversions the single being a 7.4L Mercruiser 300hp so I am presuming with a few modifications it will be okay

Guys I am listening to your arguments but they are based on one glaring thing which is Resale. I didn't buy this boat to sell it a d I didn't buy this boat to make a profit I bought it to stay on it use it at the weekends on the river Medway as far as the Thames estuary and enjoy it if I sell it later in life then so be it but please stop suggesting that the worse reason for doing something is resale value
 
There just does not seem to be a set available and I've been quoted £15000 for replacing two engines and drives and that's used
 
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The challenge is that resale is the key to viability.

You dismissed option 1 on the basis of not financially viable, which I and I assume others take to mean that the cost of the engines plus the cost of the boat exceed its worth.

If you had something that cost £5k and was worth £100k done then you have lots to play with.

In this case two of the single most expensive components in the boat have gone!

I wish you well and look forward to hearing what happens in due course.
 
There just does not seem to be a set available and I've been quoted £15000 for replacing two engines and drives and that's used

So assuming that instrumentation etc can then remain as is, and the boat will be as supplied you are in £20k for a boat worth who knows - lets say £20k being optimistic - so it could be a lot worse.

I dont know the price of the single engine, but by the time you have properly glassed the hull, changed instruments, throttles, fuel connections and so on you might not find that there is actually that much in it. Anything for boats is amazing money and it all mounts up.
 
Thanks Bruce I'm looking at the single Engine option as the same boat was sold with either twin or single Engine Conversions the single being a 7.4L Mercruiser 300hp so I am presuming with a few modifications it will be okay

Guys I am listening to your arguments but they are based on one glaring thing which is Resale. I didn't buy this boat to sell it a d I didn't buy this boat to make a profit I bought it to stay on it use it at the weekends on the river Medway as far as the Thames estuary and enjoy it if I sell it later in life then so be it but please stop suggesting that the worse reason for doing something is resale value

As the boat came out with a single 7.4l Mercruiser option that answers a lot of dubious questions regarding do two 150's equal 300 re HP because it doesn't take into account where the torque is laid down and how that in turn will affect performance . As that option is now a known quantity that is the path I would take if it works out financially advantageous.
 
Guys I am listening to your arguments but they are based on one glaring thing which is Resale. I didn't buy this boat to sell it a d I didn't buy this boat to make a profit I bought it to stay on it use it at the weekends on the river Medway as far as the Thames estuary and enjoy it if I sell it later in life then so be it but please stop suggesting that the worse reason for doing something is resale value

Okay, let's remove the word "resale" and "profit" from the above paragraph.
Even then, you're left with "value", which still stands, I think.

e.g. What's the value of a boat that needs £15k worth of engines and can be bought with engines for £20k?
It's not all about the numbers, I agree, but it does help to be realistic about where the money is actually going when you are weighing up the options.

.
 
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Okay, let's remove the word "resale" and "profit" from the above paragraph.
Even then, you're left with "value", which still stands, I think.

e.g. What's the value of a boat that needs £15k worth of engines and can be bought with engines for < £20k?
It's not all about the numbers, I agree, but it does help to be realistic about where the money is actually going.

I concur, yet I have undertaken many car and bike restorations as a hobby and pastime before and I never ever managed to sell them on for half of what I put into them. Not every undertaking has to be a business model, there are many motives and driving forces other than financial that drives us to do the things we do.
 
OKi when I said that option one was not financially viable is because I figured that it was something that had to be outlayed in one go rather than say the individual jobs associated with the other two options for example for the single inboard there was the individual mods work and then the engine itself.
 
I think you are now facing the dilemma that the former owner of your boat faced .............and he gave up and sold it to you, even with a good amount of DIY skills you are facing a task that will require a considerable outlay of time and cash. Have you thoroughly looked over your core boat is it in good shape? Here is a surveyers report on a similar boat:
http://www.yachtsurvey.com/boatreviews/sundancer_290.htm

He points out a few things you should look at. Having removed the engines the previous owner stopped work....... there will be reasons for this and you should try and work out what those reasons were???

In a job like this its the little things and what you uncover as you delve into the work that will chip away at your budget and patience. As well as those things that could be overlooked, For example craning in one or two engines and out, when trial fitting at a boat yard is going to cost also lifting and fitting/overhauling secondhand drives drives is probably going to cost, factor in things like new filtration extra fuel lines, engine wiring, engine controls.

Given your situation I would start building a spreadsheet of the estimates of both time and money for each option and a required cash flow this will point to an affordable option. where you are estimating times i would double each estimate because things always take longer than you expect.

Its unlikely that your existing drives would be any good for a single installation of 300hp so there is another on cost of buying fitting a drive then filling in your transom holes and cutting a new.

Then look at the running costs for each engine option........... anything petrol is going to be expensive to run and obtaining petrol in quantity maybe a wind up because of the lack of suppliers on the river and the rules of filling cans at filling stations, fuel consumption data is available on line, even at a modest cruising speed a 7.4 petrol is going to be £60 -70 hour - A 300hp diesel might be half that but more expensive to buy in the first place.

Remembering that this project is going to require cash and stamina to get to your end point - what starts out as an interesting project can soon become overwhelming and abandoned........ so you have to be questioning yourself before committing, remembering that if your on a limited budget you won't be able to throw cash at this to make the hard problems go away.

It may be that you are going to conclude it will be easier and cheaper to buy a boat that's a going concern!!!

I posed a similar question recently for my Triana , which is over twice as old as the Searay, the forum responses basically concluded that I would never get my money / investment back. Like you, I said this was a labour of love, not for profit but I concluded in the end it was probably best to stay with what I have 2 off 150hp petrols from 1986.
 
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'Guys I am listening to your arguments but they are based on one glaring thing which is Resale. I didn't buy this boat to sell it a d I didn't buy this boat to make a profit I bought it to stay on it use it at the weekends on the river Medway as far as the Thames estuary and enjoy it if I sell it later in life then so be it but please stop suggesting that the worse reason for doing something is resale value'

fit one outboard and it will go up and down the river just fine.
 
There just does not seem to be a set available and I've been quoted £15000 for replacing two engines and drives and that's used

But you don't need two engines and lots of power to go up and down a river.

One smaller outboard on the back should do it - as it will weigh a lot less than your original engines and drives you might not even need to put in too much ballast elsewhere to balance it up.

And if you really want a backup motor - an even smaller outboard on a folding bracket will do the trick.

At this kind of price and age, as long as it all works, someone will buy it from you in the future so you don't even stand to lose a huge amount of money if you ever want to sell it on.
 
That is something I've considered using a Panther Marine Swim platform bracket as a temporary solution.

The above points are some of the main concerns that made me look at an outboard conversion. I know it's not the done thing and it will affect resale but I really don't care about resale. I'm in touch with a professional that does these Conversions and really knows his stuff. And the plans we are discussing are sounding great.
 
Big thread here on a US website https://www.thehulltruth.com/boatin...conversion-project-wellcraft-st-tropez-5.html
Seems to be popular in the US. I was in Fort Lauderdale two years ago and saw a few older boats converted with big outboards.
It would be worth examining the practicalities around transporting fuel to your boat. Some marinas have rules about he handling of fuel. You would need to be on a marina with decent access to your car and you would probably need a suitable trailer to transport the fuel tanks or a specialist fuel bowser.
There was a very enterprising petrol station in Cork Harbour situated beside an old stone pier. The owner bought a bowser and you could ring him up and get a delivery to the pier. It was very popular with big ribs and petrol sports cruisers in the area.
 
That is something I've considered using a Panther Marine Swim platform bracket as a temporary solution.

The above points are some of the main concerns that made me look at an outboard conversion. I know it's not the done thing and it will affect resale but I really don't care about resale. I'm in touch with a professional that does these Conversions and really knows his stuff. And the plans we are discussing are sounding great.

I presume your chosen cruising area is tidal, you will have consider how much power you need to push against the tide and keep moving forward? its a question I cant answer but somebody hereabouts must know??
 
To be honest it's the river Medway boat will be based at Wateringbury where the limit is 10mph and its non tidal and occasionally popping up to the Thames estuary areas with trips along the Thames. So not really needing massive power
 
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