Trader 41' displacement hull - engine size

[superheat6k]

Was shown details of a lovely looking Trader 41' today, but propulsion limited to 2 x 120HP Ford diesels.

I have no doubt they can propel the boat to hull speed of say 8 - 9 knots in a flat sea, and will be economical, but will they do that with a force 6 wind on the nose, and with a decent swell running.

Is 2 x 120 HP too light for a 41' displacement hull, i.e. have I been shown a river boat ?

I would have thought at least 2 x 200 - 250 HP more realistic for safe seagoing use. Looked to be a nice boat though.

 

[sarabande]

I think you'd need to find what sort* of props have been installed, and what sort of revs the engines will run at.

*number of blades, pitch, diameter, cupped, thickness.....

 

[superheat6k]

I think you'd need to find what sort* of props have been installed, and what sort of revs the engines will run at.

*number of blades, pitch, diameter, cupped, thickness.....

Indeed never really looked that closely at the Tarquins previously. Immense boats, but having now had a look around I can see newer models with typically twin VP 306s and for less AP.

Possibly too similar to the Turbo 36 I have just left.

 

[oldgit]

My 36 foot Broom hulled beast has 2 x 135hp Perkins Engines.It probably weighs considerably less than that boat you are interested in.
Engines are virtually new and probably producing 99.99% of quoted power.With the usual stuff aboard and bit of water and fuel we MIGHT get 13/14 knots flat out at a struggle.
Happy cruise at around 10 ish knots.
All the Turbo 36s in the club, even those with the weedy engines leave me choking on their fumes as they disappear over the horizon.

 

[longjohnsilver]

Our DeFever 48 has twin 135s which is more than adequate for the size of boat, so I'd be very happy with 120s in a 41 footer. I reckon that most of our cruising is done using about 90hp in total.

 

[Greg2]

Our DeFever 48 has twin 135s which is more than adequate for the size of boat, so I'd be very happy with 120s in a 41 footer. I reckon that most of our cruising is done using about 90hp in total.

+1
If we are talking solely about displacement speeds then twin 120hp is absolutely fine IMHO. If you want to go faster then no question that they are too small.....but I am guessing that wasn't the intention when they were fitted.

 

[Whopper]

There are a few traders around my parts. While 2x120hp is fine for displacement cruising my impression is that these boats roll a good deal so when the going gets rough it would probably be more comfortable with bigger engines.

 

[oldgit]

If you have been used to having a decent lick of speed at the end of your throttles as with the T36 would be very aware of just how glacially slow displacement speeds can appear be when you have any decent distance to cover .
Much better to creep around on tickover and have the speed available than to be pushing the engines beyond what is comfortable in order to complete a journey that is starting to become worrying or wearysome. ?
Am mystified as to why you would want to swap a cracking spacious seakindly all round boat with all known faults sorted for a slow rolly overpriced anachronism of dubious build quality. and quite probably somebody elses money pit ..

 

[Latestarter1]

Was shown details of a lovely looking Trader 41' today, but propulsion limited to 2 x 120HP Ford diesels.

I have no doubt they can propel the boat to hull speed of say 8 - 9 knots in a flat sea, and will be economical, but will they do that with a force 6 wind on the nose, and with a decent swell running.

Is 2 x 120 HP too light for a 41' displacement hull, i.e. have I been shown a river boat ?

I would have thought at least 2 x 200 - 250 HP more realistic for safe seagoing use. Looked to be a nice boat though.

You are quite correct to estimate a hull speed of 8-9 knots and I expect engines are Lehman Fords which are 'honest' SAE J270 hp and actually the same as or slightly more powerful than Oldgits engines which are Perkins motors to the old SAE141a 1971 standard.

If we take a SWAG of 13 tonnes displacement running at hull speed suspect you will be taking less than 50% load out of the engines at hull speed and top out at around 13 knots at WOT clean.

All sounds like a sweet package to me.

 

[Forty_Two]

Consider that nearly all Grandbanks42's had the 120 hp engines till the late 80's some had the 108's. Perfectly powered for displacement speeds.

What will slow you down in the heavy stuff is the motion not lack of power. More flare on the Trader so may slam more than my GB. We installed fin stabilisers, marvelous!

My GB42CL had the 108/120's, never really sure which, till we re powered with Perkins Sabre 135's, only due to wanting no issues when we took her to the Med. Used to cruise at 8, can do 9 now (10 @WOT) but usually stick to 8, very relaxing.

 

[superheat6k]

If you have been used to having a decent lick of speed at the end of your throttles as with the T36 would be very aware of just how glacially slow displacement speeds can appear be when you have any decent distance to cover .
Much better to creep around on tickover and have the speed available than to be pushing the engines beyond what is comfortable in order to complete a journey that is starting to become worrying or wearysome. ?
Am mystified as to why you would want to swap a cracking spacious seakindly all round boat with all known faults sorted for a slow rolly overpriced anachronism of dubious build quality. and quite probably somebody elses money pit ..

The Turbo 36 was a cracking boat, but just wasn't right for us. I really don't get the modern trend to get bigger and bigger boats. I can handle a 40' twin screw (now !), even though they do become a handful, but mooring space becomes limited, pre-planning everywhere you go becomes the order of the day, and costs go up with the square of the waterline length.

Also the Turbo 36 was not suitable for coastal cruising from the lower helm, unless you are prepared to play Russian Roulette with pot markers. So I got fed up with being Billy No Mates up on the Flybridge.

Having cruised under sail just a few sea miles I am really quite used to just 5-6 knots (or slower tacking to windward), and most of the past two years on OB were at displacement speed, indeed the World's crustacea growing on the props by mid-Summer in the brackish waters of the upper Hamble meant that by early August she was struggling to plane anyway. Opening up the TAMD60C s was pleasant, but most of the time She was throttled back to either ~16 or even just 8-9 knots.

However, my brief foray into the 41+2 was simply to vary my interest in something until I can view more of the Corvette 32 I really want, which will be next month over in the CI. However, interesting comments, and I have myself questioned whether I was simply viewing a worse version of the Turbo with the Trader.

Yes the Corvette has a flybridge, but also a better field of view from the lower helm, a more sociable deck layout, will be easier to park and moor, with the go faster option as long as I find one with the 200HP or larger engines, which sadly rules out at least half of the bunch currently available.

The other thing is that I like, really like the Corvette. It was what I was seeking when I found the Turbo 36, and it is what I still hanker for now.

Sadly the blinkered view of the vendors that boats presented like a Council rubbish tip will easily sell their boats rules out a further significant quantity of the few that are available presently - either that or the descriptions simply do not reflect the actual condition, and many of the advertised claims are damn right lies, with completely unrealistic price expectations.

I would say if anyone does want a serious long distance smaller displacement cruiser there is the best example of a secondhand boat I have ever seen available in Plymouth - google Cygnus 32. This boat is truly immaculate, and a credit to its vendor, but sadly not for us either.

 

[Deleted User YDKXO]

Indeed never really looked that closely at the Tarquins previously. Immense boats, but having now had a look around I can see newer models with typically twin VP 306s and for less AP.

Possibly too similar to the Turbo 36 I have just left.

Coincidentally many years ago when I was boating in the UK, a friend of mine had a Trader 41+2 with Volvo TAMD61A 306hp engines whilst I had a Turbo 36. His T41 maxxed out at about 18-19kts but he generally cruised it at 16kts. Even at that speed it rolled a lot in a beam sea and it was a very wet boat throwing up a lot of spray. I can imagine that at displacement speeds, the T41 would roll even more and I think you'd find the motion at sea to be very different from your Turbo. On the other hand they are big boats and they are great party boats with that enormous aft deck

IMHO, if are interested in a T41+2, you should stick to models with bigger engines such as 306hp which at least give you the option of getting a move on if you need to. Just make sure you buy some good wet weather gear

 

[MapisM]

Fwiw, the estimates I made with my 53 feet/35 tons trawler, based on prop demand curves (engines, being mechanical, don't give all the real time numbers you can get nowadays with electronic instruments), tell me that I'm using 60/65 hp each side to cruise at 8/8.5 knots.
Therefore, I would agree with LS and all others who said that 2x120 is perfectly fine for a T41, if you are happy to use her at D speed.
Otoh, as others pointed out, she has rather a SD than a pure D hull, hence rolling could be even more of an issue than it already is anyway, in all D boats.
Some kind of stabilizers would be a much more than just nice to have equipment, I reckon.

 

[Deleted User YDKXO]

Otoh, as others pointed out, she has rather a SD than a pure D hull, hence rolling could be even more of an issue than it already is anyway, in all D boats.
Some kind of stabilizers would be a much more than just nice to have equipment, I reckon.

Definitely. Stabs would be really useful on a boat like the 41+2, even at SD speeds, but I don't think Trader have offered stabs on this boat from new so the OP would be very fortunate to find a used one with stabs

 

[tamarind]

My Trader 41+2 has the VP 306hp engines. Great at displacement speeds, cruise around 9 knots and burns about 20/25 lph, if you want to speed up I've had 22 knots with a clean bottom. I've noticed that with some growth on the hull and heavy seas you need a fair amount more power even at displacement speeds.
The boat is a good 14 tons or so, so need to consider power to weight ratio and where you will spend most of your time, sea or rivers.
We love the boat for its versatility and ammense amount of space for a 41 foot boat.