Yamaha 15hp Enduro wont run - Please help!

[Tspringer]

Originally Posted by gonesail

take it to a dealer and trade for one that works

Not a chance. I specifically wanted the 15hp Enduro model 2-stroke. These engines are built very tough and they only weigh about 78lb. The new 15hp 4-stroke engines are over 110lb. That weight difference is the difference between whether I can manhandle it around some or not. I also think the 2-stroke revs faster. No 4-stroke for me!

I can get a brand new complete carburetor assembly for less than $100.... that's what I am leaning toward doing. Get me running fast and then rebuild the old one at my leasure for a spare.


Terry

[Hillbilly]

I had an experience much like that attempting to dinghie around in an anchorage in Pensacola (Johnson 2-stroke). Didn't figure it out until after I had rowed back to the boat. I had inadvartainly filled the tank to the tip-top and then forgotten to open the air vent on the fill cap. Good luck!

[a64pilot]

If you can get a carburetor here in the US, buy it. Clean the old one and keep it as a spare.
However I believe Yamaha dealers in the US either can not get or will not sell two stroke parts, don’t know which is true.

[a64pilot]

Originally Posted by Tspringer

Not a chance. I specifically wanted the 15hp Enduro model 2-stroke. These engines are built very tough and they only weigh about 78lb. The new 15hp 4-stroke engines are over 110lb. That weight difference is the difference between whether I can manhandle it around some or not. I also think the 2-stroke revs faster. No 4-stroke for me!
Terry

Maybe used to be true, and may still be for Yamaha, but light weight powerful four strokes that don’t pollute, don’t have chokes or carburetors, don’t require any warm up, don’t ever bog or foul plugs, never smoke and sip gas have been available for years. And I mean sip gas, the difference has to be seen to be believed, I think our 2.5 gl fuel tank lasts for 20 hours or so of running, seems to last forever. But I rarely run full throttle, with 20 HP, except for getting on plane, you don’t often need to.
I’ve had my little Suzuki for I believe five years or so, so far. Have even sunk it like a fool four years ago, and other than changing the oil and filter, have never had to do anything outside of scheduled maintenance, which for me is a yearly oil change both engine and foot, and I changed the impeller this year, didn’t need it, but figured five years was long enough on an impeller, but old one was in such good shape it’s now a spare.

[briblack]

I got a carb for my 15hp Enduro on e-bay, from China of course. I probably could dig up a link. Ditto on cleaning the carb, but also check the fuel hose, bulb and tank. Mine had a kinked pickup tube in the tank, and any of the bits and connections on the fuel line system can leak air under suction, so no fuel.

[sailcrazy]

We have a 2010 Yamaha 15 Enduro 2-stroke. and have had a very similar issue a few years ago. Turned out to be the clip-on connection to the remote fuel tank!!! It was not fully on and seated, and (evidently) allowed air into the line vs fuel. Check your fuel tank connection!

[skipmac]

Originally Posted by a64pilot

The Yamaha Enduro 15 weighs 40 kg, or 88 lbs. that is 5.87 lbs per hp.

The Suzuki 20 four stroke weighs 99 lbs, or 5 lbs per HP

The Yamaha two stroke Enduro 25 HP weighes 118 lbs
For 4.8 lbs per HP

For the HP the four stroke Suzuki is lighter than either two stroke Yamaha.

HP/lb is an interesting spec but for me the most critical spec is the total engine weight. Even though I can still lift 100 lbs or more that's more than I can easily maneuver around the boat, especially trying to get the engine on the dinghy transom in the water. Even the 15 Yamaha is a handful.


On the other hand, the fuel issue is huge. Didn't do an exact measurement but the Yamaha got 1/3-1/2 the run time on a 6 gallon tank than a 4 stroke we used last year on a charter. Not to mention you don't have to mess with the 2-stroke oil and mixing.


Ideally I would like a 20-25 HP 4 stroke with electric start and power trim/tilt that weighs about 40 lbs but not holding my breath for that to happen.


Any suggestions for a 15-20 HP 4 stroke that weighs in 80 lbs or less?

[sy_gilana]

You might have air leaking in at the hose connection.
As a test, connect the fuel hose directly to the filter inlet, bypassing the connector at the engine tray.
The correct fuel float height measured from the float bowl land is 14mm (Hold carb upside down to measure, only gravity acting on the float)
Avoid wire to clean the jets, you will enlarge them, messing up the ratio. (a #48 jet is 0.48mm diameter, if it gets scraped to 0.50 it will never idle.)
Get a new #48 jet for the idle circuit, and then adjust the air screw (Sometimes hidden, drill out the brass plug) to 2.5 turns out. Be gentle when screwing inward to its stop.
boats.net is a great resource for parts.


I am not sure that its an Enduro. Does it have Enduro written on the cowl? Does it have a mechanical timing advance under the flywheel? (twist throttle while looking for movement of a white ring and wires under the flywheel)



Keep the motor, Ill bet that Ockham's Razor applies! The simplest solution is the problem.

[ub1]

Had the same problem. Ordered a new carb online, less than $100. Ethanol screwed up the original one, tried cleaning twice. Replaced tanks and hoses. Same problem. Put new carburetor on, problem fixed. Double check your part numbers, enduro’s may be tad different. Use ethanol free or use treatment and stabil. The best outboard made. Looking for a used one now, or I will get a new one outside US. Happy Sailing

[a64pilot]

Originally Posted by skipmac

Any suggestions for a 15-20 HP 4 stroke that weighs in 80 lbs or less?

I don’t believe that exists even as a two stroke, it’s achievable of course, if the manufacturers would put a two stroke on the same diet they did the modern four strokes, but I don’t expect to see that. It seems that for the most part development of two strokes is at an end.

The HP per is most relevant, because it speaks to what is possible.
For instance the Yamaha 9.9 weighs the same as the 15, because it’s the same motor of course, but the 15 is the highest HP they get out of that motor.

Suzuki chose to build 20 HP as the highest, it’s likely had they chosen 15 as the max it would have weighed less than the Yamaha 15 two stroke.

Maybe someone will, who knows?

[Billnpr]

Clean the low speed jet. I have aYamaha 8hp. Same problem occoures if I do not run it once a month. I always carry small socket, screw drivers and carb-cleaner. I run non ethenal gas, but I have found that even running the carb dry, that the little gas left in the fuel line and filter will evaporate. The evaporated gas leaves a dandruf size flake that clogs the low speed jet. I can now clean the carbs on the boat in the water without loosing parts. It is much easier to run the motor once a month for about 10 monutes though.

[sy_gilana]

That 15HP motor is limited to that HP for longevity. Just like the US 9.9 and the EU 13.5 are limited versions of the 15.

It can get more but then engine life is a problem, 246cc tells the story.

On the other hand, reducing the pitch from the standard 11 3/4" to 10" gives you a whole lot more thrust, and the HP/Mass discussion is moot. Selecting the correct propeller is probably the single most important economy factor. If you can plane, 3up, with your hull config at about 1/3 throttle, you are doing well. Our dinghy is a Terhi Micro-Fun from Finland. ABS Double hull PU foam filled. Heavier than any deflatable.

We have a 1998 63V version. Still going strong. (Commonly known as 15F)


The correct carb for the Enduro is a 6B3–14301–00
The correct carb for the non-Enduro is a 63V-14301-00

They are identical apart from the 6B3 (model identifier) has a brass anti tamper plug covering the idle mixture screw.
They are interchangeable.

To the OP, I really think you are getting air sucked in. The 'O' ring at the connector is prone to failure if the spigot is not greased. Also make sure it clicks fully in.

Please report your findings, I love to learn new things.

[belizesailor]

Originally Posted by a64pilot

I don’t believe that exists even as a two stroke, it’s achievable of course, if the manufacturers would put a two stroke on the same diet they did the modern four strokes, but I don’t expect to see that. It seems that for the most part development of two strokes is at an end.
....

Not quite, Evinrude did a clever thing...instead of going 4 stroke like the rest of the herd, they went high tech 2 stroke. Theirs is the only 2 stroke I know of which can still be sold in the USA market.

Unfortunately the smaller versions of their ETEC engines are relatively very heavy...partially due to the fact they include unecessary features on them like electric start and power tilt.

Here in Central America the 2 stroke Yamaha Enduro still rules the market by a wide margin because they are simple, rugged, and can be repaired with basic hand tools. There are distributors for the ETEC, but I almost never see the motors except in larger HP ranges.

For a smaller dinghy motor, to be used in remote places, I would still prefer a good old Enduro. Anything short of a catastrophic failure I can get it going again with basic hand tools and spares. If the ETEC has a brain fart...you are done.

[Vasco]

Originally Posted by sy_gilana

You might have air leaking in at the hose connection.
As a test, connect the fuel hose directly to the filter inlet, bypassing the connector at the engine tray.
The correct fuel float height measured from the float bowl land is 14mm (Hold carb upside down to measure, only gravity acting on the float)
Avoid wire to clean the jets, you will enlarge them, messing up the ratio. (a #48 jet is 0.48mm diameter, if it gets scraped to 0.50 it will never idle.)
Get a new #48 jet for the idle circuit, and then adjust the air screw (Sometimes hidden, drill out the brass plug) to 2.5 turns out. Be gentle when screwing inward to its stop.
boats.net is a great resource for parts.


I am not sure that its an Enduro. Does it have Enduro written on the cowl? Does it have a mechanical timing advance under the flywheel? (twist throttle while looking for movement of a white ring and wires under the flywheel)



Keep the motor, Ill bet that Ockham's Razor applies! The simplest solution is the problem.

Are you sure the idle screw is 2 1/2 turns? I always use 1 1/2 turns on 15 Yamaha not Enduro model.

[rbk]

The etecs also have a shorter life span and higher maintenance schedule than older 2 strokes. Last year Yamaha brought their 2 stroke viking 540 back to the North American market by simply adding a carb heater to meet emissions standards. The market wanted a simple reliable engine and they listened.