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  #1  
Old 05-31-2009, 06:19 PM
Stumble Stumble is offline
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Lightweight outboard

I currently am using a Nissan 4 stroke 3.5 hp engine to power my sailboat. The engine works great, but at 40lbs it is a struggle to get it off the transom and downstairs while racing. I have been thinking of getting a http://www.smalloutboardmotor.com/20hpoutboard.html just for getting in and out of the harbor, but I know nothing about these engines and would love some feedback if anyone has some first hand experience.


The boat - Olson 30
Weight 3600
Crew another 1500
The current engine at 25% throttle will push the boat at 6kn


I also would appreciate any other recomendations for <20 lbs outboards out there.
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Old 05-31-2009, 06:55 PM
Rangerspeedboat Rangerspeedboat is offline
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Thats just a weed eater with some modifications. Look at this thread for some interesting ideas.

Weed eater engine conversion

It would not be that hard to make your own little outboard like that.

Do you really want to hear a weed eater/chainsaw until you get out of the harbor?
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Old 05-31-2009, 09:44 PM
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thudpucker thudpucker is offline
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Some kid on a local lake has one of those Weedeaters in a 'mud boat drive' configueration.
Awful racket. The worst part was watching this kid go by foooorrrrrrreeevvveeerrrr and he was in a skiff about 10-12' long.
He was making all of 3 Mph.
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Old 05-31-2009, 10:46 PM
Stumble Stumble is offline
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Well from my slip to the open water is about 1/4 of a mile. I would sail it, but harbor restrictions preclude that which is why I am looking for some other solution.
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Old 06-01-2009, 07:26 AM
mydauphin mydauphin is offline
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Nissan made a great little 2 stroke 2-3hp, 20hp you can't get lighter than that. It had a built in gas tank.
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Old 06-01-2009, 07:34 AM
Rangerspeedboat Rangerspeedboat is offline
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The smallest,lightest outboard that I have ever seen/used is my Cruise and Carry 2.7 HP. It's not that fast, but its very light, you can pick up with 1 hand. They even built a little back pack for it. Its a small air cooled 2 stroke, with F-N clutch.

I dont think they make them any more, but every once and a while you see them on eBay.

Here is what I'm talking about- http://smalloutboards.com/cc27.htm Its already sold though.

Some people say that they are loud, well not near as loud and annoying as a weed eater. All I can say is that they are very reliable, once you get it tuned right it willl start on the first pull every time. Mine does.
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Old 06-01-2009, 09:55 AM
tom28571 tom28571 is online now
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Hi Stumble, Since you are racing your Olson 30 (what else would you do with an Olson 30?), you must have some strong guys on the rail. Let one of them do the heavy lifting. At that, 40# is not very heavy and the little Nissan is a far better motor than the one you are looking at. Such an engine is, as already said, very noisy. The oil mix ratio also says it is not very clean. When I had a small air cooled engine on a sailboat, I did not like it very much but had to admit that it was very reliable unless I tried to run it a top speed for very long. In that case, it would overheat, seize up and stop.

If you calculate what the penalty is for having 40# on the transom, you may think about just leaving it there while racing. Lots of people do that and don't think twice about it.
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Old 06-02-2009, 02:22 AM
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I don't think outboard manufacturers purposely make heavy engines infact the opposite is true spending fortunes on competing with competition for a light weight motor.

By "down stairs " your mean below? So why do you have to walk 1/4 of a mile with it??????

I dont understand why you just dont leave it where it is.
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Old 06-02-2009, 02:46 AM
Stumble Stumble is offline
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Frosty,

The EPA changed the regulations on outboard motors a few years ago forcing manufacturers to stop selling 2 stroke outboards in the US. This forced them to move to 4 strokes which are about double the weight of a 2 stroke for the same horse power but does allow for a cleaning burning engine (I guess).

I don't have to walk the engine a 1/4 mile, I only have to motor about a 1/4 mile to get to open water and put up the sails. The problem is that removing it from the transom to put it below is a pain in the a$$ due to it's weight. So a lighter engine would make this a easier take.

As for why not leaving it in place... Well the boat weights 3600lbs. So a 40 lbs engine comes in at about 1% of the total empty boat weight. Then it is placed as far aft as possible making the boat stern heavy... Then most likely the shaft and prop will get drug through the water at some point. All of which slow the boat down. Not a huge amount when cruising, or day sailing. But while racing, where every second counts it matters.
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Old 06-02-2009, 07:26 AM
Rangerspeedboat Rangerspeedboat is offline
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Well at 17 lbs, a Cruise and Carry outboard sounds just right for you. I dont know of any light weight 4 strokes, that you can buy off the shelf.
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  #11  
Old 06-02-2009, 09:07 AM
tom28571 tom28571 is online now
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Quote:
Originally Posted by Stumble View Post
Frosty,

The EPA changed the regulations on outboard motors a few years ago forcing manufacturers to stop selling 2 stroke outboards in the US. This forced them to move to 4 strokes which are about double the weight of a 2 stroke for the same horse power but does allow for a cleaning burning engine (I guess).
No 2 strokes for sale in the US? Guess I've been asleep. When did this happen?
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Old 06-02-2009, 10:52 AM
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What about lifting with a halyard and lower it down the hole?

Or use the boom!!
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  #13  
Old 06-02-2009, 05:04 PM
Stumble Stumble is offline
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Frosty,

that is what we have been doing, but it is still cumbersom and a pain compared to having a lightweight engine to start with.
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  #14  
Old 06-17-2009, 05:38 PM
nimblemotors nimblemotors is offline
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Electric outboard

I built an electric outboard for my 26ft sailboat. It is very light compared to the 8hp outboard, because the weight is mostly in the batteries to run it, not the motor itself. It was actually a lot more work than I thought to do the conversion, but it sounds like this is what you need if you want lightweight.

Have you looked at the big trolling motors? If 2hp is all you need, they will do.
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  #15  
Old 06-17-2009, 05:52 PM
masalai masalai is offline
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I am not sure if you would consider going in this direction but anyway, have a look at Torqeedo electric outboards the 4.0R uses 48V and is fairly powerful for "hull speed applications (I an using 2 to push my Bob Oram 39C sailing cat when needed and the 4.0R weigh in at 16.5kg... There are other models offering the equivalent of 2 hp and 6 hp using 24v battery power (reverse thrust is not stunning as the propellor is optimised for forward thrust/efficiency)...
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