Just curious

[Seafood]

Hi, i am not familiar with larger or diesel powered sailboats. Could someone explain why they have separate transmission and throttle controls. Is this only applicable to diesel motors? Is it only on older diesels? Also, do any brands/models of boat or motors incorporate it into one unit(like a gas powered motor boat)? Just curious
TY

[Cwens]

I'm going to guess that it's some combination of tradition and a desire for bulletproof mechanical simplicity.

[HeywoodJ]

Our diesel-engine boat has single lever controls. Morse. Quite common. We have two engines, so I suspect it is more common there, otherwise we'd have four levers, but certainly the products exist and do get used, I guess it comes down to preference. To make a single lever work there is a fair amount of equipment out of view below the deck/lever, so, for places where the controls are installed on a steering pedestal I could see that being an issue, after the steering gear there just isn't much space in the pedestal for the mechanical bits of a single-lever control.

[Yellowtulip]

I can’t remember seeing anything other than single-lever controls here in the UK.

[MicHughV]

Here in the US, single-lever throttle/gearshift levers are typically found on your center console fishing boats.
Sailboats not so much. Can't think of any I've ever seen. Might be some, but I'm not aware of them.

[TrentePieds]

Seafood:

The reason for the separate throttle and transmission controls is simple: The motor is one mechanical unit, the transmission is another mechanical unit, discrete from the motor, although connected to it through a device called a "spline shaft" which is not visible from the outside of the motor or the transmission when the two are bolted together.

Because the two "devices" are discrete, each has a control device upon it: for the motor it is the "throttle", and for the transmission the "shifter". In yachts these two controls are often independently controlled from the helmsman's station via two "Bowden cables" each connected by a control lever, so that there are two separate levers. That system is what I have.

To save the helmsman from having to think about what he is doing, a device called a "single lever control" has been invented. This device is so designed and constructed that operating the single control lever causes the two control cables, and therefore the two controls, one on the engine and the other on the transmission, to operate in the required sequence.

Whether the engine is gasoline fueled or fueled by diesel oil has nothing to do with the matter. Nor has age. Nor has whether you are contemplating a sailboat or a motorboat. And you can install a Single Lever Control on any gas engine-transmission or diesel engine - transmission combination.

So now that that is clear, why did you ask the question?

TrentePieds

[rslifkin]

Split levers are simpler mechanically. Newer electronic controls are almost always single lever though.

Personally, with a single engine, I have no strong preference (maybe a slight preference to single lever). On twin engine powerboats, I strongly dislike single lever controls and much prefer split levers.

My own twin engine powerboat has gas engines and split controls (4 levers). Unlike a single where maneuvering is often done with 1 hand on the controls and 1 on the wheel, most close quarters maneuvering is done with the engines. So the more precise throttle control (due to longer throttle travel) with split levers is preferred, as is the hard stop at the end of travel when engaging the gears (no risk of accidentally going above idle).

Thinking about it, my preference also goes a little bit with how much idle thrust a boat has. If you're typically docking by just bumping in and out of gear at idle, that leans more towards split controls. If you're frequently adding throttle, then single levers start to be more convenient.

[leecea]

All the newer sailboats boats I've been on are single lever controls. That said, they've all been production boats from the mass market brands. I did encounter twin lever controls on an older Catalina. IMO it wasn't a big deal either way.

[TrentePieds]

Seafood:

I agree entirely with rslifkin. His answer goes a bit beyond what you asked about, but it is something you will find comes into play once you start handling ANY kinda boat.

rsl talks about "bumping" in and out of gear. You will find that even in a puny little 5-ton sailboat like TrentePieds with but a single engine, "bumping" is in fact how you control your speed when you are going slow, such as when you are docking. The "throttle" remains in "idle", which for TP is about 950 RPM on a 20 HP diesel with a 16"Diameter x 14"Pitch propeller. That yields about 3 knots - MUCH too fast for docking and for any close-quarters maneuvering. Therefore, to slow down you have to stop the propeller turning by leaving the transmission in "neutral". From lying dead in the water to moving a one knot requires "forward gear" for but 20 seconds or so. Then you come back to "neutral", and it will take another 30 or 40 seconds for TP to lose all her speed and lie "dead in the water" again.

Boats don't have brakes, so you must use "reverse gear" to slow down as well as to "back up". Driving a boat is NOTHING like driving a car, so put your knowledge of driving cars out of your mind. Get someone to take you out in a boat and show you how boats behave and what is required to "steer" them.

TURNING a single-engined sailboat at slow speed, when you are precision maneuvering, REQUIRES constant use of "throttle" and "gears". This is one time when, as rsl says, the single lever control has a slight edge over the dual lever control. The rudder works only at higher speeds. Get your teacher to show you why :-)

While underway in open water at cruising speed the engine controls are not used for quite long periods of time, and one system is therefore as good as the other. However, when precision maneuvering is required and you are constantly accelerating and slowing, such as within marinas, I find that for sailboats, double lever control is MUCH handier than single lever control.


All the best :-)

TrentePieds

[Fore and Aft]

Seafood most yachts I survey have a single lever control. I prefer it myself as that is what I have always had on the various yachts I have owned.
I have been onboard various vessels when some shocking docking situations with twin lever engine controls have happened. The normal scenarios is coming into the berth it all turns to custard and the owner gets flustered. Next thing you know he has hit the throttle lever and just revved the diesel to max rpm without actually moving the boat. Then in panic he tries to put the boat in gear and can't or the best one was when it clunked into gear and the boat almost leapt up onto the marina dock. Either way I have seen that extra lever fluster less experienced skippers.
We have an Autostream feathering propeller on our yacht which has the same pitch either in forward or reverse. It works well and with just a quick burst in reverse using our single lever engine control can stop our yacht fairly quickly.
Cheers

[Seafood]

Thank you for all your replies. I was mainly asking because hopefully sooner than later I'll be moving up to a larger boat and docking a larger boating seems a bit daunting. I've been motorboating for a while and have a 16' daysailer for two years so I am comfortable on the water. My main focus on my new to me boat will be shallow draft, ease of engine maintenance and something that would be easier to handle in the marina. I was thinking that the split controls would make it very complicated because I thought that both controls had a neutral spot and both would have to be manipulated. Not sure why I thought that. Really appreciate that you took your time to help me out. I have a bunch of random questions so hopefully we will chat soon.

[skipperpete]

I like individual control levers rather than compound controls for all the previous mentioned reasons but they aren’t for the un initiated. I’ve had individual levers on two of my earlier sailing vessels because of the gearbox design... one was a mechanical Lister reversing gear that would normally have a 3’ long lever directly attached to the mechanism at the gearbox and the only choice for remote shifting was to install a very heavy duty Morse type cable and a matching control lever in the cockpit. My other boat had a Gardner diesel with an actual clutch to the reduction gear driving a Hundested variable pitch propeller and a strong arm was needed to engage that clutch even with the cockpit lever.
The use of twin levers can be really demanding if docking goes south and power is needed on either or both engines. I replaced a Vulkan flywheel coupling on a Cat 3406 after the owner had a moment of confusion and engaged astern at elevated Rpm while docking at RLYC and it was actually a good thing that the damper disintegrated and his vessel didn’t destroy the marina pen. His next adventure with the control levers was entering the lifter slot at a haulout in Phuket...... this time he was already in ahead and needed astern to slow er down but got the wrong lever and hit the wall at the end of the slot with some speed , flattening the bow and shortening the boat by about 1 meter.
Alcohol seems to have been involved in both instances disproving the myth that “Chardonnay makes daddy smarter” once and for all.

[ItDepends]

People who think it is always one way, or the other can safely be ignored.

SOME sailboats have single lever combined throttle and shift, and some have separate shift and throttle levers. Some motorboats have single lever throttle and shift controls, and some have separate throttle and shift levers.

As a general rule, single lever controls are more common on newer boats, and on outboards, and on higher horsepower inboard power boats.

What ever you have, you get used to. You can make horrendous mistakes with either. I cut my teeth on the two lever controls, and my current boat has single lever controls. I have a slight preference for the two lever controls on single engine boats, but can't give you an objective reason why...

In general, people who are shifting back and forth quickly and often are most often out of control and will make a hash out of it no matter what the shifter configuration.

[ranger58sb]

Originally Posted by Seafood

I was thinking that the split controls would make it very complicated because I thought that both controls had a neutral spot and both would have to be manipulated. Not sure why I thought that.

As boats get larger, docking is almost all about gears -- and throttles during the maneuver become almost useless. That's a gross generalization, of course, and it varies with boat size/weight/windage, available torque (gas versus. diesel), prop size, etc. And there are sometimes exceptions, what with that pesky wind, current, etc... but more often than not, as boats get larger, gears are important and you never use the throttles.

Originally Posted by ItDepends

I have a slight preference for the two lever controls on single engine boats, but can't give you an objective reason why...

I can at least say why I have that same slight preference just now: I can manipulate the gear levers without looking at them. Feel (location) of each (F, R, and especially N) is easier when I'm doing all that behind my back.

Our situation often calls for slow turning and stern-to entry into a tight slip without much clearance to rotate in the fairway. Learning the new-to-us single lever system has been easy enough, but I still find myself having to turn back and look at the levers to be sure I'm where I think I am. Didn't have to do that with the separate gear/throttle set-up.

OTOH, our electronic single-lever system comes with auto sync, and that's a plus I like, too... and that may eventually overcome my preference for the doubles. Maybe.

-Chris

[donradcliffe]

A single lever control is more user friendly and much easier to explain to a new crew. I don't have any problems with the dual levers now, but it was a learning process which can be avoided with the single lever.