Is 200HP too much for the Thames?

[StevieH]

As my search for a motor boat continues I am hopeful the combined knowledge and expertise of this forum might help break the eternal circles I seem to be going in!

My basic requirements are 26-28ft, inboard diesel, shaft drive, a double berth plus an occasional second double berth. Use on the non-tidal Thames but the ability to traverse the tidal length and enjoy some coastal cruising increasingly appeals. main use would be single handed or with the admiral and occasional day trips with a couple of friends.

After much research I initially narrowed it down to a Falcon 27 Capriole ( quite spacious, good layout but generally seem in tidy rather than good condition and a bit pricey for the age) and a Saga 26 ( good layout but feels less spacious and despite being of a similar era to the Falcon seems to have survived the passage of time better).

The inboard diesel version of the Falcon only has 43hp and having taken one for a spin on the Broads I sensed it would struggle with the tidal section and is actually designed as a river boat, so coastal cruising is probably not a good idea. The Saga 26 is clearly designed for river and coastal use and of course has a more powerful engine. plus it appears to offer better value for money.

During my endless searches I have now come across a very nice looking Beneteau Antares 8 which the Admiral has taken something of a shine to. Whilst obviously much newer it is well priced compare to the two Falcons I have viewed and this one has the additional stern cockpit seating so the layout is much better and more practical than the standard version. However, as these are semi displacement and designed for coastal cruising the standard engine is a 200HP Yanmar.

So my question is -would this be suitable for regular use on the non-tidal Thames?

All thoughts and comments welcome!

TIA

 

[st599]

What's it like when driving at the speed limit?

8km/h over the ground isn't much, especially as the current can flow at 4-5.

What's the wash like in displacement mode?

 

[Anibal]

I have similar predicaments with my boat which’s is fitted with twin Yamaha 150 outboards. Also based in the non tidal Thames. Needless to say that she cruises at almost tick over (1000 RPM) in order to stick to the 5 knots limit and my only worry is carbon buildup as the engines will never get the chance to get up to higher temperatures to burn that off. Your diesel Yanmar will be fine in the non tidal Thames, specially if you are thinking about going coastal once in a while, which will allow you to open her up and blow the cobwebs off. There are much larger sea going vessels in the non tidal section and they seem to cope just fine.

 

[ianc1200]

In answer to the original question, I'd say investigate fully. I know this because I bought a boat with twin 250hp Cummins. I was told (in answer to my query regarding running at low revs) on a forum they would "idle all day without a problem ands outlive your kids grandchildren". Turns out there are multiple versions of the Cummins 6BTA's - about 15 variations - and mine had a particular fuel pump, a Nippon Denso EP9, where running for long periods in idle would cause damage. For a 38' semi displacement boat (Aquastar 38) on one 250hp engine in still water idling means 4.5 knots, so I'm guessing a 26' boat with a 200hp engine would give you problems on the upper Thames. Another issue is (on mine at least) when engaging gear even at it's lowest revs it charges off very quickly which could be tricky in locks.

Re Saga 26's - are they by the same manufacturer as "Sea Saga"? Google seems to indicate they are. There's a Sea Saga 29 at our marina for sale, but it too has a large engine, a Yanmar 220hp.

Sea Saga 29 CV — David Morris Yacht Brokerage

 

[st599]

For a 38' semi displacement boat (Aquastar 38) on one 250hp engine in still water idling means 4.5 knots,

Above Teddington, the speed limit is over the ground - so with a couple of knots behind you, you basically need steerage at 2-3 knots.

 

[Billy Blue]

In answer to the original question, I'd say investigate fully. I know this because I bought a boat with twin 250hp Cummins. I was told (in answer to my query regarding running at low revs) on a forum they would "idle all day without a problem ands outlive your kids grandchildren". Turns out there are multiple versions of the Cummins 6BTA's - about 15 variations - and mine had a particular fuel pump, a Nippon Denso EP9, where running for long periods in idle would cause damage. For a 38' semi displacement boat (Aquastar 38) on one 250hp engine in still water idling means 4.5 knots, so I'm guessing a 26' boat with a 200hp engine would give you problems on the upper Thames. Another issue is (on mine at least) when engaging gear even at it's lowest revs it charges off very quickly which could be tricky in locks.

Re Saga 26's - are they by the same manufacturer as "Sea Saga"? Google seems to indicate they are. There's a Sea Saga 29 at our marina for sale, but it too has a large engine, a Yanmar 220hp.

Sea Saga 29 CV — David Morris Yacht Brokerage

Yes, it is the same boat builder, they seem to have dropped the "sea" at some time.
In response to the original question, I have a Saga 315 with 260hp (VP D4260). At tick over speed, it goes at just over 3 knots so not a problem up the Thames at all which I have done several times.

 

[oldgit]

Beneteau Antares 8., semi displacement and designed for coastal cruising the standard engine is a 200HP Yanmar

Ideal for non tidal 8 Kph "wide decent side decks" for size or for getting a stable 20+ knot ??? move on once beyond the barrier.

 

[jandnrowe]

As my search for a motor boat continues I am hopeful the combined knowledge and expertise of this forum might help break the eternal circles I seem to be going in!

My basic requirements are 26-28ft, inboard diesel, shaft drive, a double berth plus an occasional second double berth. Use on the non-tidal Thames but the ability to traverse the tidal length and enjoy some coastal cruising increasingly appeals. main use would be single handed or with the admiral and occasional day trips with a couple of friends.

After much research I initially narrowed it down to a Falcon 27 Capriole ( quite spacious, good layout but generally seem in tidy rather than good condition and a bit pricey for the age) and a Saga 26 ( good layout but feels less spacious and despite being of a similar era to the Falcon seems to have survived the passage of time better).

The inboard diesel version of the Falcon only has 43hp and having taken one for a spin on the Broads I sensed it would struggle with the tidal section and is actually designed as a river boat, so coastal cruising is probably not a good idea. The Saga 26 is clearly designed for river and coastal use and of course has a more powerful engine. plus it appears to offer better value for money.

During my endless searches I have now come across a very nice looking Beneteau Antares 8 which the Admiral has taken something of a shine to. Whilst obviously much newer it is well priced compare to the two Falcons I have viewed and this one has the additional stern cockpit seating so the layout is much better and more practical than the standard version. However, as these are semi displacement and designed for coastal cruising the standard engine is a 200HP Yanmar.

So my question is -would this be suitable for regular use on the non-tidal Thames?

All thoughts and comments welcome!

TIA

There are quite a few Falcon 27 on the market now and Capriole versions. Try and find out what hulls they have - some have a 'low wash' designed for slow river use.
You've got a big difference in HP there (plus running costs). Diesel on a shaft is the way I went and so far no regret when I needed work done whilst in the water.

 

[paulbrown22]

I bought a Saga 26HT nearly a year ago now which I absolutely love, especially bearing in mind the purchase price - I think you get an awful lot for the money with one of those! We're based at Greenwich on the tidal Thames where it copes perfectly with the conditions and 12kn speed limit, but is equally very happy going much slower as you head upstream with the mini keel underneath providing directional stability. I delivered it ~70NM around from Burnham on Crouch when I bought it and it was also great at sea. For me only minor downside is the top speed which is ~15kn absolute max with a clean hull - for a longer coastal passage ideally I'd have ~15kn cruise and top speed closer to 20kn, but given our young children 99.9% of my time currently is spent within the Thames speed limits <=12kn. The (Sea) Saga 29
at David Morris/Titchmarsh mentioned above would give you that greater speed with it's 230hp Yanmar diesel and a second full double down below, but is over twice the price of a Saga 26HT.

I've never been on a Falcon so can't directly compare, but the Sagas are certainly very nicely built overall and great quality. Personally I prefer the Scandinavian-style galley upstairs and the protection provided by the hard top (even with the retracting canvas "sun roof") rather than the full canvas sports boat style layout of the Falcon, but that's just my preference. Personally I don't think the Antares are built quite as solidly as the Sagas, but they are nice boats and perfectly suited for the upper and lower Thames - there's one fairly close to me on the river here in regular use. I also delivered an ACM 31 Elite around to the Thames for a friend, another similar example boat with a 230hp Yanmar 4LH, again slightly lighter built than the Sagas but lovely layout and space for the size and an easy 16kn cruise/22kn max. If I had a boat with a 200hp+ diesel engine on the upper Thames I would be wanting to give it relatively regular exercise in a less restricted area, as even at 10-12kn it is still barely doing 2000-2500 RPM and I prefer the turbo to get some work! In that respect the Saga 26HT is quite well suited for the mid-Thames, as even at 12kn it's doing ~3000RPM with the turbo nicely engaged.

If you're ever down this end of the Thames just shout and you're very welcome to come for a spin on my Saga.