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Jknight611

2.5 HP Suzuki

76 posts in this topic

You're doing all the right things, Chick.  You shouldn't have a problem, as far as I've been told.

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The Tohatsu/Mercury 3.5 looks like a good option.  Same weight/displacement as the 2.5 but tuned to produce 3.5 HP.  Does anyone have one of these?

 

Do you guys have short or long shaft motors?  I'm considering getting a motor for my Spindrift, the transom is 17" deep where the motor would attach which is right on the cusp for needing a long shaft motor.  Steve W reported problems with a short shaft motor on his Spindrift, but success with a long shaft motor. 

 

Any idea what speed a loaded Spindrift would achieve with a 2.5-3.5 HP motor?  I'm interested in trying to get up a river section to a higher lake.  The river section has to be portaged up by canoe, but can paddled by kayak (sneaking up the sides).  The parks website says you need a 10HP motor to get up, but they are basing that on heavier boats, not a sleek Spindrift.

 

Thanks!

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The Tohatsu/Mercury 3.5 looks like a good option.  Same weight/displacement as the 2.5 but tuned to produce 3.5 HP.  Does anyone have one of these?

 

Do you guys have short or long shaft motors?  I'm considering getting a motor for my Spindrift, the transom is 17" deep where the motor would attach which is right on the cusp for needing a long shaft motor.  Steve W reported problems with a short shaft motor on his Spindrift, but success with a long shaft motor. 

 

Any idea what speed a loaded Spindrift would achieve with a 2.5-3.5 HP motor?  I'm interested in trying to get up a river section to a higher lake.  The river section has to be portaged up by canoe, but can paddled by kayak (sneaking up the sides).  The parks website says you need a 10HP motor to get up, but they are basing that on heavier boats, not a sleek Spindrift.

 

Thanks!

 

 

I bought a new long shaft Tohatsu 3.5 for my CS 17 completed this summer.  So far, I am really happy with it.  I ordered it here, http://onlineoutboards.com/  and was quite happy with the service, price and delivery.  I run it on alcohol free gas, and so far, no issues.

 

JP

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17 inches is the correct transom height for a short shaft motor on a planing powerboat. It leaves the cavitation plate a little below the bottom to prevent cavitation. But on a sailboat where the stern is either clear of the water or near it, and the motor is mounted off center, the prop will lift clear of the water in anything but the calmest conditions and when the boat heels over in the wind. You'll need to lower the motor by notching the transom, or go with a long shaft motor. If you are only using the motor in "power boat mode", on the center of the transom, you should be ok with the short shaft.

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You guys kill me!  Everyone says "I love my Suzuki", and then go on to tell about all the hydro-lock problems you're having.  What sort of experience would it take for you to NOT like your 'zuki?

 

It's called cognitive dissonance.  :P

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Like djnost said ethanol is just a complete disaster for lawnmower engines and other small engines.  The lawnmower service guys I use hate it. 

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The problem isn't the fuel, so much as the industry's needing ethanol tolerant soft parts, like gaskets, O rings, diaphragms, seals, hoses, etc., not being large enough to worry about. The automotive industry is huge, so the soft parts manufactures have formulated rubbers and synthetics for these parts, with their related tooling. Larger marine gas engines (inboards and I/O's) can use slightly different ethanol/marine formulations, because most are automotive applications that are marinized. The tooling is the same, just a different marine formulation. The small engine industry just doesn't have the volume, to get these manufactures to push the marine formulations through their tooling, so we're stuck with non-compliant hoses, O rings and the like. It's a numbers thing and when they figure out how many yards of any particular diameter hose they want to run with a particular formulation, they have to justify the costs of cooking up the special mix, for these limited production runs.

 

The automotive industry isn't imune from this either. For example, most carbureted engines have used rubber tipped inlet needles for a few decades, replacing the solid brass ones that tended to dent in time. The rubber tip lasted longer and could conform to slight irregularities on the seat too. To date, I know of no ethanol compliant rubber tipped needles, even for automotive applications. The only option is a fuel stabilizer, for those engines with non-compliant hoses and other soft parts. You'll still have to deal with sludge, if you leave fuel in the system, but you will have longer times, before you have to pull things apart and the fuel system in general will be cleaner too. Even with ethanol, fuels are much better today, in terms of being cleaner, containing anti-oxidizers, anti-coagulants, etc., so do get fooled with the old school fuels that are still available. Odds are, in spite of the ethanol, your engine will like the new stuff better. The only exception to this are leaded fuel engines, without hardened valve seats. For these I'll still recommend a new fuel, but also a lead additive, so you can have the lubrication, along with the other benefits the new fuels bring. All you need to do is pull the plugs after a hard pull and compare their condition with and without the new fuel additives. These new fuels are one of the reasons you can leave a set of plugs in the holes for 150K miles. Try that with an old school, leaded fuel engine. For those of you that don't remember, we changed worn out and fouled plugs about every 10K miles and an engine that had 100K miles on it was done, worn out, burning oil, had had its valves reseated at least once and generally was used as a new mooring weight.

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PAR, I also heard that ethanol fuel breaks down faster than non-ethanol fuels.  (The source for that info was an on-line video about snow blower repair.)  If that is true, it makes sense why it's less of a problem in automobiles than small engines.  Cars use it up too fast for it to be a problem, but outboards and snowblowers are often used seasonally or sporadically.  Without stabilizer, problems start sooner.  I am fortunate to have two gas stations near me that sell ethanol-free gasoline.  I always use this for my small engines.  Using stabilizer is still a good idea, but it is imperative, if using gasoline containing "strechanol".

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Automobiles also have a closed fuel system.  Unlike tanks used on boats there is no vent which means no moisture laden air getting in while fuel is being consumed.  I saw a gas pump in GA that was labeled marine gas.  It supposedly had no ethanol mixed in.  Not sure why this isn't an option in more places.

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 The tooling is the same, just a different marine formulation. The small engine industry just doesn't have the volume, to get these manufactures to push the marine formulations through their tooling, so we're stuck with non-compliant hoses, O rings and the like. It's a numbers thing and when they figure out how many yards of any particular diameter hose they want to run with a particular formulation, they have to justify the costs of cooking up the special mix, for these limited production runs.

 

The automotive industry isn't imune from this either. For example, most carbureted engines have used rubber tipped inlet needles for a few decades, replacing the solid brass ones that tended to dent in time. The rubber tip lasted longer and could conform to slight irregularities on the seat too. To date, I know of no ethanol compliant rubber tipped needles, even for automotive applications. The only option is a fuel stabilizer, for those engines with non-compliant hoses and other soft parts. You'll still have to deal with sludge, if you leave fuel in the system, but you will have longer times, before you have to pull things apart and the fuel system in general will be cleaner too.

 

These are all of the unintended consequences of trying to make gas out of corn and forcing people (in my state, at least) to use it.  Auto parts makers aren't going to go back and re-tool their production lines for carbeureted engines when fuel injection became common a quarter century(?) ago.  If I"m not mistaken, there were reasons alcohol was abandoned as a fuel source over 100 years ago. 

 

The guys at the lawnmower repair shop said, I think per Hirilonde's point, that ethanol basically turns into varnish when exposed to moisture and oxygen. 

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All modern fuels, with or without ethanol have several additives, some of which remain when the fuel evaporates out of a fuel system. Fully pressurized fuel delivery systems suffer much less from this, but atmospheric systems do. Yes, ethanol does cause moisture gain (hygroscopic), which when mixed with the additives can lead to gum, varnish, etc., but more importantly is the corrosive properties of this created mixture of moisture, ethanol and the additives. Again, synthetic and rubber formulations have been made to address these issues, but taking on limited, special production run applications, for a relatively small market isn't a good business model, so . . . My research shows ethanol tolerant hoses down to 1/4" (6mm) are available, but only in automotive applications on the smaller sizes. Marine applications only down to 3/8" (10mm) in ethanol tolerant. This leaves small engines out in the cold, replacing soft parts as a regular maintenance routine. A buddy of mine runs a landscaping business and stops by twice a year, to have hoses and pieces replaced. He's learned what happens if he doesn't.

 

Ethanol free fuels are still modern formulations, with their additives, so varnish and gum will still show up. It takes a little longer, but it still happens. Dave, all automotive fuel systems have tank vents, pre-pump, so moisture still accumulates in the tank and is pumped through the system. On most cars as mentioned, this is used up quickly enough that it's no issue, but park the car with a little fuel in the tank for a long time and watch what happens. Fuel stabilizers use coagulants to keep the additives bound up to each other, so they can be drawn up and burned when the engine is eventually started again. In fact, modern fuels do the same thing, except they don't use as much per ounce as the stabilizers do, so it doesn't last as long. This said, you're still better off with modern fuels, as the old school stuff will quickly show you why, they've added all the seemingly junk, to the new stuff.

 

Alcohol has some benefits and disadvantages to consider as a fuel. The political reasons for its use is now questionable, but entrenched with the congressmen responsible for this subsidy. If trade with Cuba improves as a result of recent changes, sugarcane will come to play and possibly make changes in the ethanol market. I see ethanol as a short lived experiment, but time will tell.

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The Tohatsu 3.5 does move the 17 quite well,  I attached a ring on a bungee to pull the mizzen sheet forward when the boom is let out.  IN practice, this has worked out very well.  The motor does develop varnish on the jets as stated before.  In a couple of months, I'll pull the carb, clean it and start fresh.  Give me my old Johnson 4 hp, 2 cycle anyday.  20151012_121734.jpg

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Just a note about oil level in the 2.5 hp Suzuki.  For the first time, I loaded oil into a new (and dry) 2.5 Suzuki: exactly .4 quart of oil, the recommended amount.  The oil-level-view-window showed the oil at the "min" level near the bottom of the window.  The "max" level was shown as near the top.  I can't [now] find my photo [of it], but when I do, I'll post it.

 

Point being, if one fills the oil using the oil-level-view-window as a guide, the likely result may be that it's overfilled.  That could lead to problems much in discussion.

 

 

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Good point Pete.

 

I had a volunteer fill my oil and he way over filled it. It was totally my fault as I was distracted and I did not inform him about the sight gauge or the importance of not over filling. I had a syringe from WEST on board and it did not take much effort to to bring it to the correct level. 

 

Before the EC I just drained the oil because it was easy and it is a tiny amount. I had no idea if my ground crew would remember not to lay the motor the wrong way. I taped a 6" length of blue masking tape to the cowling and marked it "no oil". 

 

I decided that it was cheap insurance and because the motor is still fairly new it would be nice to give it new oil.

 

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x2 on Pete's advice.  The level shown in the window seems able to vary quite a bit depending on whether the motor is straight up or angled, and whether it is rotated on the vertical axis as for a turn.  So, taking Pete's advice a step further, it would be a good idea to drain the oil, then refill with the 0.4 quart, then find the orientation in which the window shows "min," and use that as future reference position.  Thanks for info.

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Well, in full confession, I may have overfilled the motor on the hydrolock event I described early in this thread.  Doesn't seem to use oil at all, now I keep the level slightly below the center of the window. We just returned from a trip that the engine layed in it's cradle ( tiller down) for a long trip, no hydrolock problems noted.  Seems to run fine, may it continue for a long while! 

 

 

Been good sailing on the southcoast lately!  Y'all come on down! 

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When I poured in the 0.4 qts of oil, I was careful to have the motor's shaft vertical.

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Just a thought on fuels from a pilot's perspective. Mogas is not used in GA and light commercial aircraft because: 1. it is less well regulated for quality and consistency; 2. the aromatics in it can damage and sludge tanks and; 3. because it has a much shorter shelf life than avgas. The assumption is that mogas at service stations normally gets turned over fairly quickly. Ethanol fuels are not used (as in illegal in Australian aviation) because they absorb moisture very quickly. I have seen demonstrations that show that one flight in moist air at 10,000 ft can result in a frightening amount of moisture in the fuel. Sailing being a moist environment (irony) I would think that ethanol mogas is going to absorb a fair amount of moisture the longer it sits in a fuel tank, and that will affect running of the engine and sludge formation in the carby as well as internal corrosion. I wouldn't use ethanol in an outboard motor just in case.

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