Tips on docking stern in with twins

[JV II]

I never drove a twin engine boat until I splashed 3 weeks ago. I'm writing this to show what I've learned. I'm still learning.

In many situations, I need to shove off and dock alone. I don't want to be the guy who yells at the admiral :smt021, so she just sits there looking pretty, keeping my son quiet.:grin:

In ideal conditions (no wind and current) a twin engine boat handles just like a Bobcat. You can spin and turn just fine with the throttles. My pivot point is on the transom. That I knew. :thumbsup:

The conditions are never ideal. There is always wind and current. :smt115 That I underestimated. :smt009

First two times docking, there was apparently minimal wind and current. It was a swish into the slip those first 2 times. :thumbsup: Never exceeded idle on either engine. No dock help. Didn't even touch the dock or neighboring boat. I looked like a champ. :grin: A confidence builder, but led to overconfidence. :smt018

I don't touch the wheel at all when within 100 feet of the entrance to the marina. By playing with forward/reverse idle I can keep a line and turn the boat just fine. I don't have to exceed idle. :wink:

Third time, some current at the mouth of the marina. Felt the lighter end (bow) get pushed. Predicted this and the needed compensation. No problem, just put the upcurrent engine in neutral and kept the down current engine at idle speed and straight away I went down my line. Occasionally I put the upcurrent engine in reverse for a second. Learned how to expect that and how to compensate for it. :thumbsup:

Fourth time, some current, but still not sure how much a factor that was. The wind was 15-20 mph. All canvas up, of course since the temps here have yet to go above 65. Went about my usual procedures and learned despite 5 tons of displacement, I might as well have been a 19 foot sailboat. Overshot the slip before my turn. :wow: Went into reverse and got blown toward the slip and the bow anchor of my neighbor's 260DA. :smt119 Some how managed to avoid collision, backed past the slip and got centered between rows, tried approach again and overshot again. :smt013 This time reversed and with a little frustration (maybe slight panic:smt119), the bow wasn't coming around as easy. Departed from the usual procedure of staying in idle. Muscled the throttles and got the boat back and into a turn, made it, but got pushed side to side with the neighboring boat when my stern was at his centerline (both of us with plenty of fenders out so, no damage). :smt021 Tied up with heart in my throat. What happened? Failed to compensate for the wind (maybe current too).

Fifth time out, having gone over it in my head many times, I left the dock with a fraction of the original confidence. :smt100 The wind conditions were the same. I learned how to predict the current and from the previous experience with the wind. :smt115 Coming back to the dock, radio off, 4 year old off, I started my pivot as if I was aligning for the slip to port. Kept shrottles in idle. Made the turn. Drifted slowly to starboard and I played the throttles to keep my alignment and back to within inches of my portside dock. playing only the port throttle in reverse backed me in and kept my alignment (I think I nudged the starboard throttle forward once or twice. It was almost a swish, except that I drifted into my neighbor to starboard once I was all the way in. No problem, safe and sound. Fenders deployed, just kissed it. :thumbsup:

Lessons learned. Figure out the wind direction and current direction, obviously. Most importantly, realize the bow of the boat swings away to leeward pretty quickly when perpendicular to the wind. You can in some cases use that to your advantage as I learned later on approach to the gas dock. :grin:

Deploy the fenders on the leeward side. That's where they will be needed.

I'm getting this. I still am unclear if I can always do this in idle. I don't think I could have swung the bow or kept my line the forth time out without using the throttle.

This is fun and challenging, but part of me wants the joystick on the next boat or at least a bow thruster. I can't imagine how the single engine 260DA's do it. Good thing he's leeward and downcurrent. :smt043

 

[dpvandy01]

Wind will affect your boat far more than current in most situations. There is just much much more freeboard + canvas to catch the wind as opposed to below the water line.. Good luck with the learning, a push pole, fenders and ocasionally a beer or cigar for the dock neighbors goes a long way:grin:

 

[Skuza]

I always check the flags first as I'm coming in for a "landing". Sorry to use the airplane term but so many things seem like they'd be the same when flying a plane. You have to plan your approach to compensate for the wind. Goosing the throttles sometimes is the norm with a gas boat as you don't have that much torque at idle. You get a feel for your boat and plan for it. Practice makes perfect!

 

[rondds]

master yoda has taught you well, young jedi!

mike, all of your observations are spot on. you DO have some steerage control in reverse (esp with B3s) but you are best served by NOT touching your steering wheel, as you have figured out already.

do NOT be afraid to goose the engines to get some response, but use quick controlled bursts. too much and you will overcompensate and err on the other side.

on your sig pic, it looks like you have a semi-private slip, probably a piling at the end of the finger dock. thus you cant really use pilings to pivot off. where we are, once you get the aft 2 feet in btwn the pilings, you can almost come straight back and let the rubrail and piling straighten the boat out (see pic below), even if your angled all out of wack. you have it much more difficult. i have learned that the pilings are our friends and wind can be used as a bow thruster!

best thing i've ever done was go out on the river and practice backing down onto a white no-wake marker from ALL angles. gives you a chance to see how the boat reacts to the all outside forces.

you've also figured out that silence is golden in these circumstances. no stereo, no one asking you dumb landlubber questions, all kids seated and muzzled, all pets tucked away.

the only other thing you have NOT encountered yet is the guy coming OUT as you are coming IN. this can really screw up your approach and make things much more interesting. but we'll cross that bridge when we come to it!

 

[jrirvine1]

Mike, your skid steer comparison is a good one, although the Bobcat is a lot more responsive.

I had basically the same set up you have on my 300 except with a little more beam. The problem you are experiencing with the wind and current is due to the position of the outdrives (off of the stern) and how close they are together, due to the relatively narrow beam. This restricts how quickly the boat can pivot. If you had a V-drive boat with larger props, positioned further in from the stern and further apart with a few feet more beam, the turning would be much more responsive.

But, you can also use the turning feature of the outdrives to direct your thrust in difficult situations. In windy conditions, you want to turn as quickly as possible and then back straight in. What I would do in this situation is proceed down the fairway, close to the docks until the bow would align with my first piling. Then turn the wheel hard to port or starboard, apply thrust to both engines to turn the boat very quickly. Next, with the boat turned and ready to back in, center the wheel and then use the sticks only to finish the docking. To center the wheel, without an indicator, I found that from hard over it took exactly 2.5 turns of the wheel to center the outdrives.

It is not “unmanly” to use the wheel when docking.

 

[comsnark]

Frankly. . . .I have real problems backing my boat with any kind of crosswind.

I probably don't get enough practice, as my home mooring is a dock with no neigbors.

Also, I have noted that if the boat goes "forward" straight and I suddenly put both engines in reverse, the boat is not backing straight unless I make a wheel adjustment. That's probably not right. . .but I have not the foggiest how to fix it (or if I can).

At my favorite watering hole. . I either go parrallel to a dock, bow in, or grab a mooring. The winds are NEVER calm enough for me to attempt a stern-in docking

 

[JV II]

Frankly. . . .I have real problems backing my boat with any kind of crosswind.

I probably don't get enough practice, as my home mooring is a dock with no neigbors.

Also, I have noted that if the boat goes "forward" straight and I suddenly put both engines in reverse, the boat is not backing straight unless I make a wheel adjustment. That's probably not right. . .but I have not the foggiest how to fix it (or if I can).

At my favorite watering hole. . I either go parrallel to a dock, bow in, or grab a mooring. The winds are NEVER calm enough for me to attempt a stern-in docking

I assume with your set-up you have the props turning in opposite directions. If not, it would explain why you don't go straight when backing up. A single wheel will swing the transom in the direction of the rotation. Twin singles spinning in opposite directions would cancel that effect. One technique used on boats with one prop is to learn the direction the transom swings when you reverse and use it to your advantage while docking. Perhaps you can do the same with your Alphas.

 

[dpvandy01]

Comsnark,

Are those twins counter rotating? if not that much prop wash is sure to move your stern. Just a thought

 

[Pakmule]

Comsnark,

Are those twins counter rotating? if not that much prop wash is sure to move your stern. Just a thought

Yeah, my '87 has both props going the same way. It is a bear to back up.

 

[JVM225]

My twin I/O's turn the same way and they tend to push the stern to the left when I put them in reverse. I'm certainly no expert, but I try to use it to my advantage and plan accordingly when I swing the bow around to set myself up to back into a spot.
I often use just the port engine to line up the stern between the poles when backing up knowing that it will move the stern to the left. I find that crabbing it a little (short bursts between reverse and neutral) helps me control things. Once the swim platform is directly between the poles I shift both engines into reverse for a split second to back the rest of the way in then let the momentum take me the rest of the way in.
I also use my steering a little bit to help things along. I've put a piece of black electrical tape at top dead center on the steering wheel to mark the position where the outdrives are straight.
The most important thing I've learned is that throttle is almost never the answer when backing up. It is especially hard to stay off the throttle with I/O's because of the control for both shifting and throttle for each engine being on a single handle. It is way too easy to accidently give the engine(s) throttle when backing up in a stressfull situation.
The best advice was from the poster that recommended that you turn off the tunes and have the kids sit quietly until the boat is safely in the slip. I have my kids trained to disappear into the cabin when I get close to the slip and they know to stay below until I tell them it's safe to come back out.

 

[comsnark]

No, they are definately counter rotating. I suspected that one of the drives was being a bit flakey going into reverse. . .(i.e. not always in gear when I think it is); but the shifting was tested and adjusted prior to launch.

I have not tried it much so far this season; but my impression is that this behaviour is unchanged. Certainly, I have no issues when I am splitting throttles when approach I approach dock from the bow. . .but things seem a bit different when backing up. Almost like there is some play in the steering. . .and "dead center" forward is slightly different than "dead center" when backing.

And my boat has seperate shift and throttle levers. . . so no chance of messing that up while docking (of course. . .it is possible to shift the engines into neutural while at 3400 rpm. . .but that is a seperate issue which we watch out for!)

 

[Presentation]

The concept of not touching the wheel is for boats with inboards.

With all the respect as a fellow Club Sea Ray member, I would discourage depending on fenders to protect your boat and your slip neighbors. The answer is not to put out more fenders, the answer in a I/O boat is to use the wheel.

Do it as you see fit. If someone gives you crap for touching the wheel, push them off the dock into the drink.

I was told over and over not to touch the wheel. “It’s like a bobcat” they said. BS. The pivot point is completely behind the boat. OK, you’re backing into the slip. Wind is pushing you away from the pier and to the slip neighbor’s boat. Turn the dang wheel! If your dock is to starboard, turn to starboard and give it some gas in reverse. If your bow is swinging away from the dock the concept of putting one engine in forward and one in reverse to swig the bow back works just as well with the engines turned in any direction as they do when they are straight.

Find a area and practice where there is no wind, current and no boats around. You can actually get the boat to crab sideways via a sea saw process. Turn hard over to the dock. Reverse to pull the stern to the dock. Next turn away from the dock and goose it in forward. Repeat. About every other time put both engines in apposing gear and swing the bow toward the dock.

After practicing at a long open wall by our pump-out station with no boats around and no current and no wind, imagining boats were tied where none were and trying different techniques I have proved to myself that Sea Ray gave me a wheel to use so I use it.

Just a warning, if you drive a inboard and come up to my boat making fun of me for using the wheel I promise you that you will get pushed in the drink so you better not have your cell phone in your pocket or its toast.

 

[CSR_Admin]

A boat with I/O's should most certainly be treated like an Outboard boat as they essentially have the same thing going on aft of the transom. I/O boats are not meant to be operated like a bobcat and this misconception is typically a great contributor to trouble docking. The pivot point is not at the back of the boat on any inboard or outboard boat, the pivot point is more towards the front. On an inboard boat it is about a third of t he way back from the front and on an outbourd or I/O boat it is the very front of the boat. Hence the popularity of bow thrusters. If the pivot point was at the back stern thrusters would be more popular. To prove this, while you are tied up next to a T-Head on the port side put your port engine in forward and your sb engine in reverse - I gaurantee your stern will hit the dock and once against the dock the bow will eventually make its way to the right. This is because the boat is pivoting at the front, if it was pivoting at the back the bow would move away from the dock and the stern would not hit.

So with that established lets look at I/O's, they have smaller props than equivalent inboards, they are sitting further aft in the water so they have more work to do, and they are typically mounted closer together making them even less effective in bobcat mode.

So when you are wanting to practice the twin inboard thing with your I/O boat thats one thing, its a great platform to do that on. But if you actually need to get into a slip and look like an efficient pro then turn the wheel, you only even need to use one engine.

 

[tobnpr]

I've never owned a sterndrive, so I'm ignorant here.
But sterndrives offer directional thrust, just like outboards. I don't have a choice with inboards, no steerage in reverse- but with IO's you can just point them in the direction you want to go (wind/current issues aside).
Why wouldn't one use that to their advantage when docking?

 

[kazie]

There a three items I added to my 29' Sundancer that make life a little easier for me when docking. First a installed a Automatic trim tab retractor, having one tab down while the other is retracted while in reverse will definitely alter the ability to control a boat when backing into a slip. Second, I mounted a flag on the bow rail which informs me of the actual wind conditions at the slip. Third, I installed a Davis position indicator so I know exactly the position of my outdrives, in my marina I need to use the steering wheel to maneuver thru the marina to my slip, once I'm at my slip I need to quickly have the outdrives centered and immediately start backing into my slip.

 

[mrsrobinson]

I never drove a twin engine boat until I splashed 3 weeks ago. I'm writing this to show what I've learned. I'm still learning.

In many situations, I need to shove off and dock alone. I don't want to be the guy who yells at the admiral :smt021, so she just sits there looking pretty, keeping my son quiet.:grin:

In ideal conditions (no wind and current) a twin engine boat handles just like a Bobcat. You can spin and turn just fine with the throttles. My pivot point is on the transom. That I knew. :thumbsup:

The conditions are never ideal. There is always wind and current. :smt115 That I underestimated. :smt009

First two times docking, there was apparently minimal wind and current. It was a swish into the slip those first 2 times. :thumbsup: Never exceeded idle on either engine. No dock help. Didn't even touch the dock or neighboring boat. I looked like a champ. :grin: A confidence builder, but led to overconfidence. :smt018

I don't touch the wheel at all when within 100 feet of the entrance to the marina. By playing with forward/reverse idle I can keep a line and turn the boat just fine. I don't have to exceed idle. :wink:

Third time, some current at the mouth of the marina. Felt the lighter end (bow) get pushed. Predicted this and the needed compensation. No problem, just put the upcurrent engine in neutral and kept the down current engine at idle speed and straight away I went down my line. Occasionally I put the upcurrent engine in reverse for a second. Learned how to expect that and how to compensate for it. :thumbsup:

Fourth time, some current, but still not sure how much a factor that was. The wind was 15-20 mph. All canvas up, of course since the temps here have yet to go above 65. Went about my usual procedures and learned despite 5 tons of displacement, I might as well have been a 19 foot sailboat. Overshot the slip before my turn. :wow: Went into reverse and got blown toward the slip and the bow anchor of my neighbor's 260DA. :smt119 Some how managed to avoid collision, backed past the slip and got centered between rows, tried approach again and overshot again. :smt013 This time reversed and with a little frustration (maybe slight panic:smt119), the bow wasn't coming around as easy. Departed from the usual procedure of staying in idle. Muscled the throttles and got the boat back and into a turn, made it, but got pushed side to side with the neighboring boat when my stern was at his centerline (both of us with plenty of fenders out so, no damage). :smt021 Tied up with heart in my throat. What happened? Failed to compensate for the wind (maybe current too).

Fifth time out, having gone over it in my head many times, I left the dock with a fraction of the original confidence. :smt100 The wind conditions were the same. I learned how to predict the current and from the previous experience with the wind. :smt115 Coming back to the dock, radio off, 4 year old off, I started my pivot as if I was aligning for the slip to port. Kept shrottles in idle. Made the turn. Drifted slowly to starboard and I played the throttles to keep my alignment and back to within inches of my portside dock. playing only the port throttle in reverse backed me in and kept my alignment (I think I nudged the starboard throttle forward once or twice. It was almost a swish, except that I drifted into my neighbor to starboard once I was all the way in. No problem, safe and sound. Fenders deployed, just kissed it. :thumbsup:

Lessons learned. Figure out the wind direction and current direction, obviously. Most importantly, realize the bow of the boat swings away to leeward pretty quickly when perpendicular to the wind. You can in some cases use that to your advantage as I learned later on approach to the gas dock. :grin:

Deploy the fenders on the leeward side. That's where they will be needed.

I'm getting this. I still am unclear if I can always do this in idle. I don't think I could have swung the bow or kept my line the forth time out without using the throttle.

This is fun and challenging, but part of me wants the joystick on the next boat or at least a bow thruster. I can't imagine how the single engine 260DA's do it. Good thing he's leeward and downcurrent. :smt043

Frankly we have never had an issue docking with twins, though we do not have kids so I am sure it's a challenge with 1 child, yet alone twins. OK, I could not resist. :grin:

You will come to love twin screws and wonder how you ever lived without them.

I encourage you to read the chapter in Chapmans on twin screws....very good infortmion and it will explain how it all works (rotation, angles, winds, pivot points, all that good stuff).

 

[mrsrobinson]

Oh, and I do understand your not wanting the admiral to participate, been there done that, bought the t-shirt......but I encourage you to let her get her hands wet/dirty as much as possible. You never know when you will need her to dock/handle the boat in an emergency situation, where you cannot.

 

[DragonAnchor]

I am Cpt Bligh when I dock!

I now lock the kid below and the admiral stays seated.


The new 290 catches ALOT of wind even with all canvas down. My worst docking experience involved lots of wind and a "helpful" guest who thought they could just jump off the boat and haul it in with one rope. Didnt even wrap it around the cleat. So when the boat didnt stop, they dropped the line. Now I had 25' of line snaked out the back, in the water and drifting down the fairway towards others and no one left on board but me!

Only thing to do was throw it in neutral to avoid fouling the props, haul the line in and jump back in the helm. spin the boat in the fairway and try again. This time ignoring the knucklehead yelling at me to "throw him the rope".

I find it much less stressful if I just single-hand the boat in docking situations. Although this one time, I did find a helpful dockmate who knew what to do and what not to do.

Right or wrong, I always use the wheel. Its how I learned to dock with the single screw 260DA.

Life has gotten alot easier now docking, I moved slips all the way towards the bulkhead. There is tons of room and I have finger piers on both sides of the boat. Cpt Bligh has retired and all the crew is happy now!

 

[mrsrobinson]

There is nothing worse then someone trying to help you dock, they grab a line and start tugging on it and throw you way off. They pull hard on the stern line, I am trying to swing the bow over and they send it right back out. I know they are only trying to help, but....

If we have guests on the boat we tell them to sit tight and let us take care of the docking since we have a "plan". It's our nice way of saying "get out of our way".

 

[Presentation]

A boat with I/O's ......the pivot point is not at the back of the boat.....To prove this, while you are tied up next to a T-Head on the port side put your port engine in forward and your sb engine in reverse - I gaurantee your stern will hit the dock and once against the dock the bow will eventually make its way to the right. This is because the boat is pivoting at the front, if it was pivoting at the back the bow would move away from the dock and the stern would not hit.....

Hey Jim,

I agree with most of what you said except the location of the pivot point.

I did try to follow your logic. Unfortunately, since I do not know what a T-head is I could not follow it.

Perhaps its terminology. The pivot point is the point that does not move, only changes in direction. If you imagine a child’s teeter totter the pivot point is the exact point where the plank of wood is resting on the support.

I believe my pivot point is several feet behind my transom, about where the propellers are located, here is why:

I went to a long open wall along a dead end channel at our marina. There is no current and it was a calm day plus the area is protected buy buildings and trees so neither current nor wind would c0me into play.

With the boat next to the wall on the starboard side , with my drives straight I put one drive in forward and one in reverse, and then did the opposite making the other one in forward and reverse.

Both combinations result in the stern of the boat hugging the wall. One way the bow moves away from the wall. The other the bow hugs the wall along with the stern. There is simply no way to move the stern away from the wall with out turning the wheel.

I did a 180 with the port to the wall with the same results.

With the drives straight there was no possible combination to swing the stern.

If the pivot point was in front of the bow I would have had the ability to swing the stern with the drives straight.

Let’s imagine the pivot point was in front of the boat. One of the forward/reverse combinations should have resulted in the stern swinging away from the wall.

Based on my experience the pivot point of my boat is behind the transom by a few feet.

It’s the only location that makes since from all my observations.