transom trolling motor only?

[pythonguy]

I've been scrubbing and waxing and getting her ready to put in next Wed at my new slip. They told me I couldn't use their ramp because of the ovehead powerlines and I practically had to draw them a diagram to illustrate that the mast could be lowered and the powerlines were not a problem. So now it looks like we are on for wed. but, I aint got a motor.

I'm a procrastinator, yes, and I just haven't seen one I want yet on craigslist, but for two which sold out from under me. But I do have access to a 101lb thrust 36v trolling motor with batteries.

I'm curious if that motor can push the boat around from the ramp to the slip, just a couple hundred yards, but overcoming the 3-5 knot current on the Multnomah channel and let me put off buying a motor until I see the one I want. I don't mind looking a little silly as long as I can get it to the slip, I do mind looking very silly trying to single hand the thing upriver with a weak-ass motor that can't cut it.

Any advice?

[Frank C]

Current at 3 to 5 knots ~~~~~! Go ahead & try the motor.
But take along two guys from your high school D-line and four very long oars!


Kidding .... JUST kidding! The engineers here will convert that 101 lbs. of thrust to horsepower for ya, but it seems to me it should work okay ... (maybe keep one long oar in the cockpit, too).



Edit to Add: no dispersions intended, your real answer might issue from a Scientist, not an Engineer!

[Catigale]

You cant 'convert' thrust to HP without knowing more information, they are different animals....I think a typical 100 pound thrust trolling motor will act like a 5-6HP motor...but the best way to calculate this is use the current draw and voltage, calculate the wattage used, and then use

1 HP is 746 watts

to compare power to power...electric motors are typically >90% efficient so you could knock 10 percent off the conversion to be closer still....

[James V]

I just hope that the wind is not blowing to hard with the current.

[Gazmn]

Hate to be somewhat of a party pooper but...

Would it not be better to get and install your motor before getting your boat wet?

I too, was ultra eager to get my new old boat in the drink waxing and polishing... -but Never Checked The Engine - Duh. I ended up having to get a tow from the ramp. My new Ida CB got stuck as I apparantly had some slack in the line. And was finally dragged off sideways knocking off a front guidepost the PO had put on the trailer.

I finally fixed the motor in a pitching sea Days Later. It was not fun. Ended up deciding to pull it from it's mooring for the badly needed repower I forced myself into. I am not a sailor -yet and motoring, right now, is everything.

That was my bad dunking experience. I had zero experience with a boat this size; YMMV.

But consider the hazards and or frustrations you could be setting yourself
up for:

1. If the thrusting motor is not enough power and does not give you enough control to overcome wind and or current, you could endanger your ' just waxed" boat and be a danger to others you bang into. It's never a good sound and a lousy way to meet your new, now unfriendly, neighbors.

2. Have you gone over the logistics of installing or having a new motor installed?

3. Will you be able to get back to your ramp and loaded onto your trailer with the electric motor and or guide ropes. I don't know your ramp but think this through.

Maybe you're a sailor and only need an aux to get you to and from the slip. But I think you're asking an awful lot from an trolling motor used to push or pull a boat normally half this one's size...

[Catigale]

I missed the reference to the 3-5 knot current in the original post....that is too much current for a small outboard less than 9 HP...I dont think you will make any way at all with 9HP against 5 knots of current....actually I know this as I had to run my Merc 50 HP against 5 knots in Woods Hole MA at about 4000 rpm...probably making 40-45 HP I figure..

[NiceAft]

Pythonguy,

You're letting your eagerness to sail get the best of your brain. Wait until you get yourself a real motor. The forced delay in sailing may make you reconsider waiting for Craigslist Why place yourself into a potentially compromising position.


Ray

[Mikebe]

I would advise you not to risk it. Heck, I have problems docking with a 50 HP motor with 10 knots of wind and no current. Even if the trolling motor could handle the current the slightest breeze would send you down the river.

Someone once said the art of good seamanship is avoiding situations where good seamanship is required.

[NiceAft]

Mikebe,

A slight variation of the "what is the difference between a smart man and a wise man". A smart man knows how to get out of situations which a wise man would not get into in the first place.

Ray

[March]

It doesn't sound like a good idea, especially in a current. Add to that the possible cross winds, the possible audience, the need to move the boat backwards and forwards to get it "just right," the hassle of rigging a motor which is nor supposed to be used for powering, etc, etc. And for what? Just to move a her a couple of hundred yards from the ramp to the slip? Couldn't you just use some long lines to drag her along?

You'll have to pull her out of the slip anyways just to install the new motor--a trolling motor will simply not cut it.

[Duane Dunn, Allegro]

My 6 hp dinghy motor on it's bracket will easily move my X at 6 knots with full ballast. It is enough horsepower to reach hull speed.

I would chat up friends at the marina and find someone with a 6-9 hp dinghy outboard you can borrow and clamp on the transom. With one of these motors you can easily run the boat anywhere you want at up to hull speed. Even in a 5 knot current you will make some way, but I would try and time things when the current is as slack as possible.

The biggest challenge will be the motor controls. You'll have to get to the twist grip for the throttle and the forward/reverse lever. With the helm seat flipped up it shouldn't be too bad. I've been on a number of sailboats where the throttle controls were to the side down at my feet and these worked. I would lock the motor down in straight ahead and do all my steering with the rudders. There is usually a wing nut for this.

You might consider using a spring line as part of your slip approach as this lets you keep the motor in gear pushing after you reach the dock. You don't have to immediately get it out of gear while you get the lines tied down.

[Don T]

Hello,
Yeah, I don't see the point. The only regular sailing is down at the St Helens end of the Multnomah channel anyways. You could time it for the flood tide which, depending on the time of month, makes the current flow upstream. Only on rare occasions have I been able to sail back up stream against the current.
Seems like a lot of futzin' around only to have to haul it out again. Not to say that being able to sit on the floating boat with yer honey, sippin' elixer and dining in the "atmosphere," isn't an appealing thought. Especially if yer honey needs a little convincing.

[pythonguy]

Repost... thanks Frank C.

I normally wouldn't want to put the boat in without a real motor, and I totally understand everyone cautioning me not to do it. Where the boat is current parked they are going to begin logging some of the very tall trees on the property this week, so I am forced to move it for fear of these guys landing one the wrong direction onto the boat, not to mention all the mud and flying debris. Sorry for the confusion, I can understand if some of you thought I was a hot (hotter?) head.

As it is I think the marina will let me leave it parked in their lot for a few days but that's not ideal as it's an open lot. Saw a honda 10hp go up on craigslist today and I hope to look at it tomorrow. Otherwise I might just bite the bullet and get an outboard at west marine. The last two used motors that looked good sold fast, seems to be a sellers market ATM on a solid 25-50hp 2-stroke with controls.

[pythonguy]

The guy called me back on the honda and is giving me first looks since I responded first. It's down in the water on his boat, even better. This is a 10hp 4-stroke which I think will more than enough to get me around. The 22ft training boats for my ASA class had 5hp motors and we used them right out center channel on the Columbia.

It's tiller controls, which is less than ideal, but I think i can work with it. Since my primary interest this season is sailing, I don't think I want a big motor yet. The "one that got away" from me last week though was a '73 55hp Evinrude in beautiful shape with tanks and controls, in a barrel ready to sell but the guy sold it minutes before I called! These are the motors that are hard to find, and a brand new Tohatsu goes at least 4-5K.

Anyway, any tips on managing the tiller controls under the seat when sitting? I was considering perhaps some extensions to the tiller handle, but as I haven't seen the motor yet I don't know. Shifting would be an issue if the shift is not on the tiller. Another 8hp Merc 2-stroke jjust got posted as well with shift-on-tiller. Would that be easier to control?

Duane Dunn, I missed your tip on running tiller controls from the cockpit. Thanks, I think we'll be able to manage it, I might even have the seat up with my one crewman on the engine and steer from in front of the wheel. Since I have more tiller than wheel experience this might even feel more natural.

[Catigale]

My 6 hp dinghy motor on it's bracket will easily move my X at 6 knots with full ballast. It is enough horsepower to reach hull speed.

The slippery part is what happens when you need to exceed hull speed- your HP requirement goes way up then. With a 5 knot current and a 6 knot hull speed, you have a whopping 1 knot in reserve with the 6HP...add a little wind on the nose and you are going backwards of course.

Python - for your 100 yards of moving the boat I think you will be ok, but I would have someone nearby with a tow-line ready to help out in case you got into trouble....and you probably wont get much sympathy from the CG if you do get into trouble....