390 Single Screw, Stern Crawl

[Byekurman]

I have difficulty backing my 2003 390 single screw yanmar into my slip. The boat owner next to me has purchased a new wide boat making my clearance much less. My tie is on the starboard when backing in. I back in slowly, only bumping the tyranny and the stern seems to naturally move to the port, toward the boat next to me. I do have a bow thruster. To complicate things I usually have a breeze blowing against my starboard side. Can you offer any suggestions to compensate for the port crawl and wind? (Rudder position, throttle, etc, anything else) Thanks for any help you might provide.

 

[Gdavid]

Bumps are exacerbating the situation. Your stern walks to port in reverse, a result of a right hand propeller. Prop walk is most pronounced when you first shift into gear, it does not go away but is less pronounced when you can keep it in gear. Letting momentum carry you back in neutral is best but not always practical. I would line up the boat as best as possible, turn the helm to port and start backing into your slip. When you are getting too close to you neighbor, shift into forward briefly and the stern will shift to starboard. Use the thruster to keep the bow from swinging to port and you will be set. Easier said than done but you will get it down

 

[mvweebles]

You have three turning tools: bow thruster, rudder, and prop walk.

Rudder - or more specifically, rudder wash. It's basic, but a rudder only works when there is water flowing across it. This means you can direct a blast of turning power by setting the helm hardover, then putting the gear in forward. Of course it will also arrest backwards momentum, but the rudder blast can be used to kick the stern. So at some point while backing into your starboard tie slip with the helm hardover to starboard to offset propwalk, you'll need to quickly set the helm to port, then give a "burp" of forward gear enhanced with a few hundred RPMs for a second to kick the stern towards the dock. Timing is important here: handover while in neutral, engage in forward, neutral, back to hardover starboard if you still need to go backwards.

Prop walk. As Gdavid says, you are fighting prop walk. Spending as much time in neutral is your best defense. Try fairly robust blasts in reverse to build backwards momentum, then go to neutral so you can steer in reverse. Not sure the size of rudder on your boat.

There is one last tool in your toolbox. A springline. TF member Hippocampus recently posted a technique that might work here. If you can get a line from the end of your dock finger to the aft starboard cleat on your boat, you may be able to 'lever' the stern into the finger. This technique could be a bit delicate and really needs some practice. But it might work. If it does, would definitely hold against some counter-wind.

That's everything in your toolbox. Rest is practice. I will say that not all docking situations are easy or even possible. Responses from TF members are, in my opinion, often overly optimistic and prescriptive. As if there is a magic Easy Button that will solve a particular docking challenge. Not so - there is a ton of trial and error and practice. Every boat reaponds a bit differently, sometimes inexplicably. And sometimes the results are not great.

Final words: crew communication and inclusion is very important - at slow speeds (and ehile anchoring, BTW), helmsman may be at the wheel, but often crew controls the boat. Large and ample number of fenders are your friends. And a question- any reason you can't go in bow-first? Prop walk would be working with you instead of against.

Good luck and please update.

Peter

EDIT - recent TF thread on single engine boat docking. It's a good thread with many contributions. Might be helpful.

https://www.trawlerforum.com/forums/showthread.php?t=68254

 

[Bmarler]

I usually leave the helm hard over unless there’s a long way to go. Especially if there’s a lot of turns lock to lock. Balance the time in fwd/ neut/ rev so the boat goes straight as possible. Bow thruster as needed. Steady reverse to gain momentum, harder blasts of fwd to push the stern over, glide in neutral as much as possible.

 

[psneeld]

I usually leave the helm hard over unless there’s a long way to go. Especially if there’s a lot of turns lock to lock. Balance the time in fwd/ neut/ rev so the boat goes straight as possible. Bow thruster as needed. Steady reverse to gain momentum, harder blasts of fwd to push the stern over, glide in neutral as much as possible.

 

[jleonard]

I used a different approach with my old 34 Mainship.
My situation was similar to the OP, but my slip was only 3 inches wider than my beam.
I would first assess the wind that was behind me and would blow on my starboard side after I turned to back in.
I would guess the number of slips ahead of mine that I had to start my turn. I would shift into reverse to stop the boat and turn the rudder hard starboard.
Once the boat stopped I would give it a good bump forward to start the turn
Then N then reverse and a bump to kick the arse end to port. Once the boat started to move forward again I would go back to N then bump again in reverse to further kick close the stern to port.
At that point I was usually lined up with the slip but also turned about 120 degree or facing just slightly into the wind.
I would then sit in neutral if necessary and let the wind move my bow to port.
Once lined up reverse into the slip.
IF I had doubts that I was close enough to get in I would go back out to the end of the docks, turn around and repeat.
My theory was that if I doubted I was not lined up to start over and do better. It hard to correct a bad situation once the wind takes you. But your thruster should alleviate that.
I would never touch the steering wheel once I started my turn.
So that’s another approach to the problem.
You can’t change prop walk but you can use it to your advantage.

 

[rslifkin]

I'm a fan of Jleonard's method. Even with twins, backing into my slip is pretty much a matter of getting the boat far enough over in the fairway and dropping one engine in reverse at the right timing (to slow the boat and start the turn to back in).

With a single, there may be times where spinning a 270* works better than a 90* turn as it avoids the need to fight your prop walk. Or you can go past the slip a little and back in at a different angle where the prop walk is helping to turn you in the necessary direction. And always be ready to crank the wheel and give a shot of forward to move the stern over if necessary.

 

[Hippocampus]

Agree with above and think RS sums it up nicely but would add something that’s helped me. Learn to live with the prop walk so plan for it. Before entering the slip have your boat canted with the bow to port. Then as you enter the slip a short blast of reverse. the prop walk will kick the stern to port so to miss the starboard side of the slip and the boat will straighten out so the rest of the boat won’t touch anything. Thinking wise personally found the hardest part was to do nothing and leave the boat in neutral, not touch the thrusters or throttle and just glide in from there. Using the prop walk for you instead of against you makes docking so much easier as the prop walk will always win. My tight sphincter moments when docking seem mostly from my doing to much not to little.

 

[rslifkin]

My tight sphincter moments when docking seem mostly from my doing to much not to little.

Agreed. Sometimes it's best to just pause for a second, assess what the boat is doing, and then decide on the next action rather than over-controlling the boat and trying to get it to do something "right now".

 

[Shrew]

That is a bit weird that your single Mainship 390 backs to Port. The wheel at the lower helm is on the Stbd side.

My 350 is also a single and an identical boat yours. Mine backs to Stbd. This allows me to open the lower helm door, I'm right at the midship cleat on the Stbd side and backing to the stbd side.

It would be almost useless with Stbd lower helm and lower helm door, on a boat back to port. I would find a way to get that reversed at the gear set.

 

[ranger58sb]

That is a bit weird that your single Mainship 390 backs to Port. The wheel at the lower helm is on the Stbd side.

My 350 is also a single and an identical boat yours. Mine backs to Stbd. This allows me to open the lower helm door, I'm right at the midship cleat on the Stbd side and backing to the stbd side.

It would be almost useless with Stbd lower helm and lower helm door, on a boat back to port. I would find a way to get that reversed at the gear set.

???

Our lower helm on the older Mainship III we had was on the starboard side... and prop walk in reverse was to port. I've not heard helm placement had anything to do with direction of prop rotation...

???

Then again, we didn't have a door at the lower helm...

-Chris

 

[Byekurman]

Chris, I was also confused by this reply couldn't understand why the lower Helm being on the starboard side had any impact or transmission gearing. But then what do I know

 

[jleonard]

That is a bit weird that your single Mainship 390 backs to Port. The wheel at the lower helm is on the Stbd side.

My 350 is also a single and an identical boat yours. Mine backs to Stbd. This allows me to open the lower helm door, I'm right at the midship cleat on the Stbd side and backing to the stbd side.

It would be almost useless with Stbd lower helm and lower helm door, on a boat back to port. I would find a way to get that reversed at the gear set.

All the single screw Mainship Nantuckets backed to port originally as far as I know and helms on the starboard

 

[jleonard]

And I didn’t see this mentioned so I will.
The key to getting the boat to turn to starboard in tight spaces is to shift into forward gear and give it a shot of power while the boat is still moving aft. Same for getting max prop walk go reverse with a shot of power while the boat is moving forward.
The amount of power applied controls how far you swivel.
With practice it will be easy.

 

[mmullins]

That is a bit weird that your single Mainship 390 backs to Port. The wheel at the lower helm is on the Stbd side.

My 350 is also a single and an identical boat yours. Mine backs to Stbd. This allows me to open the lower helm door, I'm right at the midship cleat on the Stbd side and backing to the stbd side.

It would be almost useless with Stbd lower helm and lower helm door, on a boat back to port. I would find a way to get that reversed at the gear set.

I agree with Shrew 100%. My boat backs to starboard and I have lower starboard helm with a starboard helm door. I find this setup a must when single-handed docking.

 

[Byekurman]

What position is your rudder is the helm hard over left hard over right or what

 

[Jeff F]

I usually leave the helm hard over unless there’s a long way to go. Especially if there’s a lot of turns lock to lock. Balance the time in fwd/ neut/ rev so the boat goes straight as possible. Bow thruster as needed. Steady reverse to gain momentum, harder blasts of fwd to push the stern over, glide in neutral as much as possible.

Yep. Me too. As long as you aren't trying to go too fast there is little point in moving the rudder back and forth.

 

[Jeff F]

It would be almost useless with Stbd lower helm and lower helm door, on a boat back to port. I would find a way to get that reversed at the gear set.

Not useless, just requiring a different technique.

I have a fairly strong preference for docking with reverse torque pulling away from the dock rather than towards it. My experience is that it gives me better control over positioning of the stern coming in, and easier reverse exit.

I don't think there is a right or wrong here.

 

[psneeld]

Not useless, just requiring a different technique.

I have a fairly strong preference for docking with reverse torque pulling away from the dock rather than towards it. My experience is that it gives me better control over positioning of the stern coming in, and easier reverse exit.

I don't think there is a right or wrong here.

The key to boat driving, especially when you run more than one, is adapting to the best capabilities of each boat.

 

[jleonard]

I agree. I’ve used prop walk to pull away most times as my preference is to dock starboard side.

 

[Jeff F]

What position is your rudder is the helm hard over left hard over right or what

If the stern is pulled left in R, put the rudder hard over left. Prop wash in F will then move the stern to the right.

 

[ranger58sb]

If the stern is pulled left in R, put the rudder hard over left. Prop wash in F will then move the stern to the right.

We didn't have to put the rudder over to get that same response.

Always walked stern to port in reverse, and stern to starboard in forward.

Might be a matter of degree, with rudder positioning.

-Chris

 

[Always Late]

Trade slips with your neighbor!

 

[Shrew]

???

Our lower helm on the older Mainship III we had was on the starboard side... and prop walk in reverse was to port. I've not heard helm placement had anything to do with direction of prop rotation...

???

Then again, we didn't have a door at the lower helm...

-Chris

Obviously the helm location has no bearing on prop-walk. And was mentioned later, 'it's a matter of technique'.

Ya, I guess, but it is significantly easier to side tie to a dock or finger pier when you reverse towards it rather than away. The bump and fill process coupled with a bow thruster makes it extremely easy.

Since my 350 is geared this way, I'm surprised a later model 390 (identical boat, simply re-badged) would change it. Otherwise, the PO of my boat was genius and reversed it.

 

[ranger58sb]

Ya, I guess, but it is significantly easier to side tie to a dock or finger pier when you reverse towards it rather than away.

Yep, sounds right to me.

-Chris

 

[Hinckley2019]

One other thing to consider if you have arrive to the dock with a closed fly bridge, open it up.......this allows the wind to pass through. A closed fly bridge creates a sail....you can reduce the windage by opening it up.

Along w/the conversations around prop wash and walking the boat.....leverage "drift" watch the wind and current ...a breeze can help push or direct you away from the dock or towards the dock.....the drift method can be very helpful when used to your benefit.

Last....if money is no object....invest in a stern thruster too w/a dedicated battery. Consider a remote control to operate both bow & stern.....takes a lot of pressure and anx during tight spaces.....

 

[Capt Ray]

We have a 2000 Mainship 390 single screw with bow thruster.

It all "clicked" for me one day after struggling with backing into our slip a few stressful times. I'm always backing in from the fly bridge.

1. the "button" controls of the bow thruster were upgraded to joy sticks. Much prefered.

2. I don't even bother with the rudder any more. I leave it more or less amidships.

3. I sit my arse on the steering wheel. My right hand is on the bow thruster's joystick, my left hand is on the Fwd-neutral-Reverse shifter.

"Its all in one's head"

4. Its like driving a shopping cart backwards! In any wind, and in any current, I can move the bow left and right (I think of it as moving my ass left and right cuz I'm facing rearwards), and of course: I can move the boat fore + aft.

Once I figured it out the shopping cart backwards analogy, I was set for life.

The best position for the shifter is in Neutral. Use Neutral more.

I just give it short pulses forward or aft, and do the same with the bow thruster.

Here are two VIDEO examples of tight landings, both in wind or current.

Play the video at the end of this post:
https://shellerina.com/2022/09/17/deliveries/

https://shellerina.com/2022/09/17/deliveries/

Here's another with side wind and chop:
https://shellerina.com/2021/07/29/tight-dock-landing-at-mackinac-island/

 

[Cartouche]

I have difficulty backing my 2003 390 single screw yanmar into my slip. The boat owner next to me has purchased a new wide boat making my clearance much less. My tie is on the starboard when backing in. I back in slowly, only bumping the tyranny and the stern seems to naturally move to the port, toward the boat next to me. I do have a bow thruster. To complicate things I usually have a breeze blowing against my starboard side. Can you offer any suggestions to compensate for the port crawl and wind? (Rudder position, throttle, etc, anything else) Thanks for any help you might provide.

Install a stern thruster as we did installed an external slepiner and worked well

 

[Capt Ray]

Here is another backing in VIDEO. Strong side winds:

https://shellerina.com/2022/04/11/time-lapse-passage-to-icw-mm-zero/

I guess my point is to not use the rudder at all.

Just use the Fwd-N-Reverse + Bow thruster joystick.... and think of yourself in a super market with a shopping cart in reverse.

Once that "clicks" for you, you'll have no problem.

Best of luck!

R&S

 

[Capt Ray]

I will say this, both Maine Maritime Academy and Mass Maritime Academy have small boat sailing programs so that the future mariners learn how to use WIND to their favor. Having grown up on sailboats, I do think I have an unfair advantage over folks who have never learned to sail... and only have experience on power boats. Understanding the effects of wind on a large ship or power boat definitely helps make wind your friend rather than your enemy.