Outboard Discussions

Thanks for all of the information. When I asked for the distance from the transom to the water I meant from where the motor hooks on inside the outboard well.

Thanks again to all.

Tom Nelson

I measured mine this weekend. Leaning over the motor to measure (200#), the top of the mounting board was 13" off the water. Keep in mind that my Ariel has a lot of weight (120# of lead and 70# of sand, plus furnishings (anchors, lines, etc. beer, etc.). My Yamaha is a long shaft

My recollection is that when I rebuilt Solsken, I determined the height of the mounting board (which is 1 1/2" higher than the original board in the well) by taking the lower edge of the boottop as the water line. Then I determined where the waterline on the motor was supposed to be. Working up from there told me how high the top of the mounting bracket/motor board was supposed to be.

Regarding the problem of exhaust smoke from the outboard motor in the lazarette: We wrapped the upper half of the lower unit with a rubber material forming a "skirt" like a mast boot that we then wrapped around the engine well. That kept the smoke out of the lazarette and allowed us to close it up and reduce the engine noise in the process. Before, the engine would choke out from the exhaust fumes if the laz was closed. Now, we can run the engine at crusing speed with the whole thing shut.

The rubber material was left over from a backyard pond project. It can be bought at any pond supply shop. We wrapped it with velcro straps that can be easily removed. The engine is free to turn for manouvering with the "skirt" in place.

My understanding is that there has to has to be a low pressure/no pressure escape path for the exhaust that comes out of the back of the outboard. In other words, if the ports are plugged, you can ruin the motor.

My problem I had earlier is that when I put a rubber "gasket" around the back of the motor and that lead exhaust down to the water out the bottom of the well, there was too much back pressure when the boat was under power and the stern/gasket dipped into the wake.

What I have done now (with my Yamaha) is to build an aluminum/fiberglass "cup" around the exhaust ports at the back of the engine, and connect a neoprene hose to carry those fumes out a small hole in the transom. After almost 900 miles of cruising this year with the motor operating at full blast about half the time (sailing on the big ponds here - Great Lakes - involves a lot of motoring and, when beating in particular, motor sailing. So, I recommend the same resolution to others.

so you have not had a problem with hot exhaust fumes and the rubber neoprene tubing? is it the same as the black fuel line you can get in (insert mega marine retailer name here)?
and is your tubing hooked up to a thru-hull on the transom? pretty high up, right?
i am starting to consider a similar system.
my current system is a pair of small copper tubings bent to point out one of the ventilation cowlings. not ideal because they sometimes don't reach and sometimes fall out, filling the laz. with fumes.
not ideal at all.

Since we are now in an era of new outboards
and modified ob wells -
perhaps a better determination of optimum prop depth
would be from the waterline on the Ariel
or Commander
to the center of the prop.

Thus, 'the center of my prop is 6" below the designed waterline on my Ariel
and it doesn't cavitate in a chinese chop.'

338's high thrust Yamaha 4/8
is 16" below the D,W,L,... and it doesn't cabitate neither,
but it's not in the water
yet.;)

The neoprene hose came from the auto parts store. The plastic through the transom fitting came from West (Its Mar... something), and the right angle barbed plastic hose fitting came from ACE.

I too was concerned about the heat before I did this. However, none of the components gets hot or even significantly warmer than the engine cover. Heat is not a problem. The only two problems I can envision are corrosion (the gasses are corrosive, I assume), electrolysis (that is why I used plastic), and a buildup of unburnt oil in the exhaust tube and fittings (I'll find out about this one when the boat is pulled for the season.)

Incidentally, I have probably burnt almost 100 gallons of gas this summer, so it has had a suitable trial period.

the only reason i ask is that my copper tubing gets quite hot after about 15 mintues of run time. This is trroublesome because my copper tubes have to be pointed out of the vent port, and it only does that when i bend it correctly to do so. of course the tubing seems to always need readjusting, and that's when i notice it getting hot. which means that maybe more of my exhaust goes through my "relief ports" than on some other outboards. hard to tell. i will check into the neoprene at NAPA here pretty soon.
-out-

That is interesting. I am assuming that you have the copper nipples going right into the exhaust ports on the back of the motor.

I didn't do it that way. I built a small plenum (about 3"long and the width of the shaft housing) so that the exhaust is perhaps cooled in this plenum. The exhaust exits from this plenum. The inside of the plenum is a formed piece of thin aluminum, shaped so it will stay attached. It is then firmly held in place by the fiberglass which covers it and extends over the shaft housing.

Perhaps this aluminum sheet, in contact with the shaft housing, is providing sufficient heat dissipation so that the exiting exhaust gas is not particularly hot. The total contact area between the lower unit housing and the formed piect of sheet aluminum is perhaps 4 square inches.

Of course, the exiting exhaust might not be as hot as well.

no fittings, just literally stuck the two copper tubes (small flexible stuff) into the two relief ports. one was 5/16" and the other was like 1/8". and they stay in there by friction, and a little bit of bend in the tubing that i stick in there. sometimes if i wiggle them, they fall out. It is a 9.9 mercury for reference.
the tubes first come out of the motor pointing down, then gooseneck up and over to the stbd fwd corner of the laz, where the vent port is.
and the copper tubing is stiff enough to stay in position, but you can bend it as needed.
but yes, it gets really hot. i would say like as hot a really hot tap water.

Your copper tubing is acting as a heat sink for the exhaust - which is probably about the temperature of hot water (since the engine is water cooled). But that is not "hot" in terms of neoprene of plastic. Being copper, the tubes readily transmit heat to your fingers (or anything else - copper being a super conductor) which is why they feel so warm/hot.

If the tubing were made out of plastic, it would not get as hot to touch.

A couple items to check with your system:

1. With the heat, and the difference in metals, there electrylysis/corrosion. You might be better served using aluminum tubing.

2. Is the seal where the tubing meets the lower unit ssolid. You might want to use some sort of sealant to be sure that no exhaust is leaking around the stuck tubes.

The fuel connectors on the newer low hp outboard engines all appear to have the same fuel connector. It is made from a plastic. The fuel line side of the connector, I learned, is easily broken. :mad:

In the following foto you will find two fuel connectors, the retaining machine screw and a new fuel connector cap for our 5 hp outboard engine. The upper fuel connector is broken -- note the exposed wire protruding from the fuel line connection point. The fuel connector cap was not provided with the engine back in 1995. Interestingly, the cap is only listed in the catalog for four stroke engines, even though it fits the two stroke engines as well.

The long machine screw holding the connector comes up through the ob's turning handle. The receiving threads are placed near the top of the connector making sure it will attach only one way. The fuel connector itself fits so tightly into the engine bay that I went looking for another fastener holding it. Took a mini pry bar to finally pop it out. I

If you have a two cycle ob without the fuel connector cap, I strongly recommend getting one. It only cost $1.75, whereas the connector assembly was $16.34.

The Mercury part numbers are:

Fuel Connector 2215781A5
Cap 878311

The January issue of Trailer Boats included the specifications for all of the current outboard engines. Those of you who want info about the Mercury Verado (16 cylinders and 275 hp), stern drives or Diesels will have to check the magazine. We are just copying listings for the 6 & 8 hp 4-cycle engines:

Engine & HP Weight & List $P

Honda 5 *----- 60-lbs $1700
Honda 8 ----- 77-lbs $2160

Johnson 6 ----- 56-lbs $1996
Johnson 9.9**--- 97-lbs $2350

Mercury 6 ----- 55-lbs $1727
Mercury 8 ----- 84-lbs $1870

Nissan 6 ----- 55-lbs $1514
Nissan 8 ----- 82-lbs $1820

Suzuki 6 ----- 55-lbs $1741
Suzuki 9.9**-- 97-lbs $2595

Tohatsu 6 ----- 55-lbs $1484
Tohatsu 8 ----- 82-lbs $1781

Yamaha 6 ----- 83-lbs $2130
Yamaha 8 ----- 83-lbs $2240

* no 6-hp
** no 8-hp

As noted before, the Mercury, Nissan, Suzuki and Tohatsu all use Tohatsu’s basic engine, although the some companies have brand specific accessories (such as Nissan's vertical pull starting rope setup).

I guess this isn't strictly an ariel related question but I use the dink to get to the ariel so it's a fairly essential piece of equipment for the ariel.
Last fall my outboard died an untimely death (it's a long, sad story), so I need to replace the out board. I had a Johnson 2.3 (dink is 8' skimmer), which was a little underpowered.
It looks like Johnson/Evinrude has gotten out of the small outboard business, I've never heard anything good about Mercurys. There's a Briggs & Stratton 5hp for $700 which I think is a bit too heavy.
I'm thinking of looking for a used one, maybe in the 3-4hp range. Are there any suggestions for what to look for or where?
There's a website www.smalloutboards.com, does anybody know anything about them?

I guess I've been away for a while--the window says I haven't visited since 2003. I don't totally believe that but the time does seem to fly by.

My understanding is that the Briggs is basically a fresh water motor only, and a throw away. I seem to have read that they vibrate quite a bit but have no first hand experience.

I have a johnson seahorse 2 for my dink, which is the back up the Yamaha 6 that powers my boat. I doubt I would go fast, but it would beat having to row if the motor gave up. I read that are looking for more power.

I might recommend you think of the dink motor in those terms, and even go so far as making the shaft lenght one of your considerations.

I purchased a British seagull as a gift for a friend of mine. I was impressed with it, and they have a wide international following. They are simple as dirt, and easy to fix. If you search on this forum, I think there are about 3 threads that mention them, but two are from someone who did not have much luck with them. That seems to be the minority opinion though.

I came across a link that gave lot's of info on Seagulls, let me go and look for it.