sailorman
Well-known member
Do you use both Sall the time or just to aid mnuveringi can see that 1at a timein non planing situation might work engine
Info pls twin engineinstalltion
- Thread starter sailorman
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Greg2
Well-known member
On our previous Broom 41 we used to run on one engine on the river or when pooling at sea. The current boat is able to run on one but we tend to use to use both, primarily because don’t usually cruise at speed so passages are longer so we often let the autopilot take the strain and it can’t cope with a single engine.
Irish Rover
Well-known member
I generally use 2 engines only when manoeuvring or in very heavy traffic or in very rough weather. My auto pilot has no issue with this. The economy is remarkable. @2200 rpm my boat achieves circa 7knts. With both running @2200 it struggles to make 8knts. Maintenance costs per engine are also reduced by close to 50%.
sailorman
Well-known member
oldgit
Well-known member
Food for thought.
When running a single engine the stern gear will be creating extra drag underway.
On inland waterways the dead engine will need to started and shut down at every lock or when mooring especially in tight spaces.
Also you cannot alternate the engines if important stuff is run off a specific engine.
ie. calorifier/power steering or battery charging.
Save a few groats on fuel by wearing out some expensive bits of boat.?
When running a single engine the stern gear will be creating extra drag underway.
On inland waterways the dead engine will need to started and shut down at every lock or when mooring especially in tight spaces.
Also you cannot alternate the engines if important stuff is run off a specific engine.
ie. calorifier/power steering or battery charging.
Save a few groats on fuel by wearing out some expensive bits of boat.?
Irish Rover
Well-known member
Whatever about extra drag, in my case at least, the numbers do the talking - 1 x 2200 = 7knts compared to 2 x 2200 = 8knts.
The previous owner operated the same regime and my engines each has over 3,600 hours on the clock and no major issues. The only thing not duplicated both sides is the calorifer and I run that side first.
Momac
Well-known member
I use both. The power steering is off the starboard engine only so that engine would be used most of the time.
Corona Mia
Member
I think it depends on what sort of boat it is, where you are travelling, and what speeds you are doing.
Afraid I have no experience of a sailing cat, but with a power boat I’ve always used both engines.
When you are on a non-tidal river and using locks (and needing minimal power) it was helpful using alternate engines with a little ‘click’……to glide you smoothly into position.
In more ‘challenging’ conditions (fast flowing river or tidal marina berthing) you might need to use both engines with a little bit more power. Either together or against each other, to turn and/or stem the tidal flow.
In all of those circumstance, it’s unlikely to find the time to start the ‘sleeping’ engine quickly enough if you need it.
When cruising…..it depends if you’re a displacement or planning boat.
I‘ve always found that most twin engined ‘planning’ boats don’t ‘plane’ on one engine.
Sometimes I’ve had to finish my ‘planning’ trip on one engine at ‘displacement’ speed!
Commercial Dave
Member
When cruising…..it depends if you’re a displacement or planning boat.
I‘ve always found that most twin engined ‘planning’ boats don’t ‘plane’ on one engine.
Sometimes I’ve had to finish my ‘planning’ trip on one engine at ‘displacement’ speed!
Our RIB is on twin 90's and it won't plane on one engine, as I painfully found out when we had a fuel pump failure at sea. It will struggle to do 8 knots even at wide open throttle. With both engines working it will do 40 knots.
I like to use both engines when while manoeuvring as you still have even thrust - if you start operating on a single engine the offset thrust will affect the steering e.g. port engine only will push the bow to starboard.
Modern boats with digital engine controls will usually have a button labelled "single" or something along those lines which when pushed, allows you to operate all engine throttles with a single lever, which is really nice for those situations where you want very precise throttle control
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Elessar
Well-known member
You are asking about manoeuvring at slow speed I presume? Use two engines in sync and the wheel or pilot to steer once in clear water.
In close quarters I’d say always use one engine at a time. Using two is the advanced class.
How you do it depends on the drive system you have. Shafts or outdrives (or outboards or IPS they are all the same for manoeuvring)
Beginner advice below.
With shafts you don’t touch the wheel until you are into clear water and engage both engines.
With the other drive systems it’s all about the wheel and selecting the engine that helps your turn. Eg with wheel left it’s right engine forward or left engine astern.
People will tell you you can split the throttles etc. And add all sorts of complications to the above. Well you can but don’t. Use one engine at a time until you have way more experience.
What drive system do you have?
47GC
Active member
Slow is pro….
