Temporary outboard for 44 footer

[GILow]

Hi all,

I'm thinking of solving a short term logistical problem by bolting an outboard on the back of my Kelly Peterson 44.

This would cover about two months where I won't have a functioning inboard.

This question is not about the wisdom of this approach, I'm well aware of the problems I'm likely to encounter, but the boat will be in the pen for the two months and all that will be needed are a few trips of a couple of miles of sheltered waterway to come and go from the slipway.

I am NOT planning to cross oceans.

With this in mind, how many horsepower do we think I need? The boat weighs about 12000 kg. 3/4 keel and skeg.

Matt

[Wotname]

The smallest one you can borrow, 9hp should be ample.

I know you didn't ask but... surely it would be easier to push the Kelly with a dinghy tightly secured to the aft quarter.

[GILow]

Originally Posted by Wotname

The smallest one you can borrow, 9hp should be ample.



I know you didn't ask but... surely it would be easier to push the Kelly with a dinghy tightly secured to the aft quarter.

With two people the dinghy idea is good, but I'm mostly solo, as you know.

I've got a decent 7.5 but I think it's a bit small. There a couple of cheap 15s on Gumtree, I'm hoping they would big enough.

[wingssail]

Originally Posted by GILow

With two people the dinghy idea is good, but I'm mostly solo, as you know.

I've got a decent 7.5 but I think it's a bit small. There a couple of cheap 15s on Gumtree, I'm hoping they would big enough.

Even singlehanding I think that using a dingy alongside would be easier than building an outboard bracket and bolting it to the hull.

The biggest problem, in my view, is controlling the outboard which will be far below deck level. Somehow you have to be able to control the throttle, the gear shift, and the steering. On my Merc all three are controlled by the tiller grip, so I could clamp on a long piece of PVC for an extension. If you have a separate gear shift then it is more of a jury rig. But you don't have to build anything. Just put the motor on the dingy (I assume you have a dingy) strap it on the stbd quarter very snugly, climb down and start the thing, then climb back up and operate it using whatever motor control you've arranged.

Alternatively, don't climb back up. Just move the boat dead man, with no body on board. You drive the whole thing from the dingy. Make sure the destination is alerted so they can tie it up when you arrive.

One thing I do know about moving a boat with a dingy. It is very unresponsive to the dingy's lame attempt at steering. You have to get the big boat moving a bit. So doing it all from the dingy, without somebody onboard to man the helm of the big boat will be dicey. Much better with two people.

BTW we moved a steel 65ft classic sloop with my 15 hp. Inertia was the enemy but it worked (with two people).

[GILow]

Originally Posted by wingssail

Even singlehanding I think that using a dingy alongside would be easier than building an outboard bracket and bolting it to the hull.



The biggest problem, in my view, is controlling the outboard which will be far below deck level. Somehow you have to be able to control the throttle, the gear shift, and the steering. On my Merc all three are controlled by the tiller grip, so I could clamp on a long piece of PVC for an extension. If you have a separate gear shift then it is more of a jury rig. But you don't have to build anything. Just put the motor on the dingy (I assume you have a dingy) strap it on the stbd quarter very snugly, climb down and start the thing, then climb back up and operate it using whatever motor control you've arranged.



Alternatively, don't climb back up. Just move the boat dead man, with no body on board. You drive the whole thing from the dingy. Make sure the destination is alerted so they can tie it up when you arrive.



One thing I do know about moving a boat with a dingy. It is very unresponsive to the dingy's lame attempt at steering. You have to get the big boat moving a bit. So doing it all from the dingy, without somebody onboard to man the helm of the big boat will be dicey. Much better with two people.



BTW we moved a steel 65ft classic sloop with my 15 hp. Inertia was the enemy but it worked (with two people).

This actually captures the whole dilemma with the dinghy. Yes, you get better control of the outboard, but you lose access to the nice big rudder on the main boat.

If I were to go down this path I'd fit remote controls to the outboard for sure. The KP44 is a centre cockpit and the wheel is a long way from the stern.

The bracket itself is a trivial job to weld and attach, the controls would take a little more work for sure, but I wouldn't attempt to move the boat without them.

Anyway, this was one of a few options I am considering, and another option just landed on the table so the question may end up academic anyway, but I'd be keen to hear more thoughts and estimates of required power for comparison.

[grantmc]

Can tow my 12 mtr 9 tonne boat no problem with a dinghy powered by a Tohatsu 9.8hp 2-stroke no problemo. Obviously pick a calm day. Tried rafting up the dink but we found we went in big circles, so towing worked best.

[GILow]

Originally Posted by grantmc

Can tow my 12 mtr 9 tonne boat no problem with a dinghy powered by a Tohatsu 9.8hp 2-stroke no problemo. Obviously pick a calm day. Tried rafting up the dink but we found we went in big circles, so towing worked best.

I never found a way to tow the main boat without someone at the helm.

[rslifkin]

For a few miles, you could lock the rudder centered and stern tow behind a dinghy. Once in close quarters, move alongside (as far aft as possible) and you should be able to push it around adequately with the dinghy. Having use of the main rudder would make docking easier, but as long as the dinghy is pushing from far enough aft it'll have leverage to pivot the boat for steering.



If you want to put an outboard on the main boat, you'll definitely want something with a high thrust prop and ideally one of the specialty high thrust units with lower gearing (Yamaha and Merc have both made them at times). A 9.9hp would likely do the job well enough, but 15 - 20 hp would be better.



Either for towing or running with an outboard you'll need pretty calm weather. If you can get a friend to join as an extra pair of hands, that'll make stuff (particularly docking if you're towing) much easier.

[Tetepare]

I push, pull, tow all the time, from broken down 45' MY to race boats w/o engines, so food for thought:

A 2hp will pull your boat, once it gets going on the right course. The question is what HP is needed to overcome wind, wave, and current. Short story, a 9.9 should do it, a 15 would be much better.

Getting the boat moving on course is the real PITA, once it's on course it's easy. A towed boat, once moving, tends to follow (see disclaimer), whereas a pushed boat (which is effectively the same as an outboard on a 44') with unmanned rudder can alter course suddenly and there's nothing you can do about it.

here's the disclaimer: I recently watched a train wreck when a 40' towed by a boat w/ 250HP the skipper threw the rudder the wrong way, and the 40' totally overpowered the 250HP, going in, well, the direction the rudder told it to.

A dinghy can be used to bump the bow back and forth, but with an unmanned rudder I'm not certain how well that would work (see above).

I've lashed to the sides, and that has some steering ability, but not enough to overpower a rudder off more than a couple degrees, or external influences of wave and current. I've seen a few race boats with 6HP on brackets side-mounted, and they do OK to get in/ out of the marina, but that's the limit. In these cases, the motor is only propulsion and the steering is with the rudder.

In dead still conditions (and maybe very little wind/ current) a solo sailor could use a dinghy to pull the boat out, bump it around to get on course, then pull it. In starting from a dead stop, the towed boats tend to slew side to side (manned rudder or not) until speed is up to about 3 knots; until then if one continues to pull and the towed boat decides to head off to port, it's going to port and pulling more does nothing except speed up the towed boat on the course it's chosen, which can be bad (see disclaimer above.)

I think for the solo sailor IF the conditions are nil/ mild, using a mounted outboard while staying at the helm is the way to go. Not sure how to control the outboard from a CC.

IF (big if?) the autopilot has a remote (my buddy has one) once the towed boat is near on-course, enable autopilot and tow or push. With the remote you can make adjustments as well. I do not have one of those new-fangled remotes.

[rslifkin]

Originally Posted by Tetepare

A dinghy can be used to bump the bow back and forth, but with an unmanned rudder I'm not certain how well that would work (see above).

I've lashed to the sides, and that has some steering ability, but not enough to overpower a rudder off more than a couple degrees, or external influences of wave and current. I've seen a few race boats with 6HP on brackets side-mounted, and they do OK to get in/ out of the marina, but that's the limit. In these cases, the motor is only propulsion and the steering is with the rudder.

In a side tow, this issue is minimized by locking the rudder to center (so it's out of the picture as much as possible) and getting the push boat as far back as possible to maximize leverage for turning. The further back you are, the more ability you'll have to move the stern sideways and rotate the boat around the keel. Tight turns will involve slowing down, rotating the pair of boats, then accelerating again. The dinghy outboard may need to be turned close to 90 degrees with lots of throttle in the turn.

[thesaltytar]

I used a 2 hp outboard (mounted on a dinghy) to push our 36' schooner between Maine and Rhode Island. We could make about 5 knots. We weigh about 9 tons.

Having the outboard on the dinghy solved some logistical problems, such as depth of prop and cavitation, even coastal work it was never a problem.

I lashed it tight to the transom and hopped back in the boat to steer (a lot more comfortable too). Had no problems. Tied some twine from the kill switch and lashed it next to me so if the dinghy somehow broke free my main engine wouldn't putter over the horizon without me.

I could dock solo by timing the approach, pulling the twine, and stepping off. How smoothly this went was, as any docking, directly and inversely proportional to the number of witnesses...

Picking up moorings was easier with a second person but otherwise I could have solo'd this with a bridle setup from the forebitts.

[fourlyons]

I pushed my 39', 23,000# keel/centerboard, skeg hung rudder, ketch for years with two Yamaha 9.9 High Thrust outboards. I usually only ran one engine, that would give me 5.3 knots, two engines gave me 6.5 knots. You can buy a remote control/cable.

[Manateeman]

Outboard. Infernal machine absolutely devoid of reliability.
Oars. Propulsion alternative supposedly used by wooden boats but without proof of concept.
“ on the hip” tow boat jargon or normal flask position for hiding booze by manatee crew.
Safety lanyard. String tied to outboard or beer.
Bollard pull. Measurement of towing power. What happens when you forget to untie dock lines.
Manifestly Unsafe Operation. Legalese in Coast Guard citation issued post collision.
Temporary. Failure expected in undefined time as in temporary dental filling.
Beer money. Compensation demanded by manatee attorneys for collision.
Push boat. Diesel powered craft used to ...push oyster sailing boats in Chesapeake bay.
Happy trails.
Captain Mark

[JPA Cate]

Hip tying, with dinghy. Helm locked amidships. When you get where you are going, use lines to warp the boat in. You can do it even with a tiny o/b, boats are made to glide through the water. Certainly a 5 horse would be adequate, but I bet you can find a friend to help you move the boat if it has to be moved during the relocation time. I agree with Wotname, but I think even a 3 hp would do it, so any o/b you have for your dinghy will probably suffice. Think of canal barges being pulled by ponies or small mules. It will help if when you are going into another slip, to have the dinghy on a long painter, so you can cast one hitch off the boat and the dinghy falls back to a longer one so it is not in the way as you enter the slip. "Don't overthink it." Oh, yeah, and do remember to have the bitter end secured!!!

Ann

[thesaltytar]

Originally Posted by JPA Cate

..., but I think even a 3 hp would do it, so any o/b you have for your dinghy will probably suffice. Think of canal barges being pulled by ponies or small mules. ..

Yes!

Captain Mark has the Sirenians but perhaps we can recruit a small but stout crew of ponies for the OP!