1 screw or 2?

[MapisM]

Funny how frequently this question pops up. As if it would be possible to answer.
You'd rather ask yourself, which boat?
The proper number of engines is invariably linked to that. It might be 4, sometimes.
Sure, there are cases where you can have the choice of 1 or 2 on the same hull, but even in those cases there is invariably one alternative which is overall better suited to the hull - and hence recommended by the builder.
So, unless your preference or needs dictate otherwise (but if so, why ask?), that's obviously the best choice.

 

[omega2]

I suppose the question to ask is, of the twin owners, How many here have been forced to come home on one engine at some point?

I haven't so far so I guess you could say that is a reason to buy a single.

single engine on a leg towed home at least six times, equal spread between drive and engine. Twin engines got home on one twice so far, break down to gearbox, and exhaust delamination, several fuel issues fixed whilst under way, they "talk" to me.

 

[ulyden]

Now I have never in 10 years at sea had any stop. Have a planing boat with 15 year old engine. The engine has no electronics. I have removed it!

To increase security, I would rather chose a backup fuel system and an extra filter. On my boat 20l tank and some 3vay valves had been enough

I avoid driving with high engine loads in dangerous areas. Speed below 90%

If a piston fail, I have still 30-40hk of the engine! By cutting fuel to damaged piston I can still take my home! (If i dont cut the fuel i got a lit of white smoke and fuel in the oil!)

Remember that the dual propellers have to much pich if you run on only one. You will not be able to get performance out of it! Then you have to put on another proopeller!

To have a new VP D4 common rail engine that stops 3 times in a season sounds strange! On larger vessels required 2 feeding pumps, sensor, 2 sets, 2 control units for log to run a single common rail engine

I dont know what people are thinking about choosing at common rail engine as a single propulsion! Theese engines have no redundansy at all. If some of the parts in the common rail system fails it stops. It could be anything from pressure controll valve to a leaking pipe, broken pickup, dead "brain", leeking nozzle or a hi pressure pump. Commonrail engines also demands much cleaner fuel. Onely advantage is better ideling performance and a cheaper engine!

 

[hlb]

I suppose the question to ask is, of the twin owners, How many here have been forced to come home on one engine at some point?

I haven't so far so I guess you could say that is a reason to buy a single.

I once had both engines fail for completely different reasons. Luckily I mended one, five minutes before the other stopped.

 

[Nealo]

It always seems to me that twin engines on P brackets are very exposed to any detritus that happens to be passing by at prop level or thereabouts. Outdrives, (and outboards) whether single or twin are surely prone to the same problem, but I suppose at least you can make an attempt to clear the prop whilst afloat??

I know opinions on the forum seem to be against outdrives but say you were choosing a twin engine boat for use inland as well as at sea, would the disadvantages of outdrives be outweighed by the advantage of being able to get at the props? (fouling being much more of an issue on inland waters.)

 

[stuhaynes]

Single or twin, pause for thought....

Hi was just wondering could you guys give me your views on the pros and cons of single engine opposed to twin thanks for your help...

Last year a close friend of mine saw an advert for a 50 foot trawler conversion, where Bridlington harbour authority had the said boat, on the dry, that they wanted rid of. Why? you ask. Simply that the single engined craft had fractured a fuel pipe and the guys on board had got nothing onboard to fix it. The 15 mile tow to Brid (was I believe) about 10 Grand! Hauled out of the water and rent on the harbour hardstanding quickly became £15,000. It's not hard to believe that the owner couldn't pay. End result, court and boat confiscated.

My own boat is 60 next year and I want To take her to Whitby. Kath, my better half, agrees, but only in the company of at least one (at a push) or two other boats.

If you're operating on the canal system one engine is fine. If you're operating an tidal rivers or at sea I'd much prefer two. If you are thinking of saltwater cruising on one engine you ought to be thinking of insurance cover and a bloody good radio, just in case.....

 

[epervier]

Funny how frequently this question pops up. As if it would be possible to answer.
You'd rather ask yourself, which boat?
The proper number of engines is invariably linked to that. It might be 4, sometimes.
Sure, there are cases where you can have the choice of 1 or 2 on the same hull, but even in those cases there is invariably one alternative which is overall better suited to the hull - and hence recommended by the builder.
So, unless your preference or needs dictate otherwise (but if so, why ask?), that's obviously the best choice.

best answer by far.