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H/V Vega
01-27-2011, 08:17 PM
You know how outboards loose power when repeatedly stored for a few weeks between uses? Well here is why and how to prevent it. This trick is not for long term - over the winter- type storage which should be done differently. It is also best for the average cruising sailors dhingy outboard - not the big monsters seen on some boats. When you take the motor off and store it without proper preparation there is fuel and oil in the carburetor. When the motor sits that fuel evaporates through the fuel jets depositing a coating much like a varnish. You cannot easily see this, but it slowly closes the jet preventing the proper flow of fuel. Do this often enough and you get a motor that is the very devil to start and runs like an old lawn mower giving little or no power. To prevent this before you take the motor off the dingy turn off the fuel and run it at idle until the fuel in the carburetor is consumed. No fuel in the carburetor means no varnish in the jets. Now you can store the motor safely and it should run perfectly when you need it again. Just thought I would share this with you. It was in our last newsletter at http://www.sailvega.com/newsletters/november2010/december.html

Bill Huson
01-27-2011, 08:41 PM
Yes, and before you run the last of the fuel out, mix Stabil with the fuel, and while you're running the last of the fuel out of the carbs, spray fogging oil in the carb throat. The engine will actually run on fogging oil so when you think the carbs are dry quit spraying. Remove spark plugs, squirt fog oil or oil oil in cylinders, spin it a few times, replace plugs finger tight - done.

Monkey Butler
01-27-2011, 09:04 PM
This is just not sound advice.

Since I'm not sure that this is the proper forum for the discussion at hand I won't expound here but everything posted above is far from best practice.

alkorn
01-27-2011, 09:34 PM
Whether it is the proper forum or not, please let us know what you think is the proper protocol for storing and outboard.

Rob Stokes, N. Vancouver
01-27-2011, 11:34 PM
Removed post

Monkey Butler
01-28-2011, 10:39 AM
Pretty much what Rob said.

There's an old saying, "Two strokes run best just before they die". This is usualy because a needle gets plugged causing a lean condition which boosts the RPM's which is followed in short order by a melted piston and/or a scored cylinder.

You may be able to get away with the OP's suggestion most of the time but it is just too broad of a statement to be good advice. Almost every carbed OB that I have worked on has drain screws in the float bowls. Use them instead.

Hey Rob, what if you have three carbs? ;-)

BarnacleGrim
01-28-2011, 10:51 AM
Not sure if it carries over to two-stroke outboards, but running the engine lean is the correct shut-down procedure for piston aircraft, at least four-stroke.

Typhoon
01-29-2011, 11:48 PM
Two stroke outboards need the lubricant in the fuel to prevent seizure. It is bad, very bad practice to run any 2 stroke with oil mixed in the fuel until it stops. Best bet with small engines is to shut them down normally, turn them so the carbs point down and let the float bowls drain out through the carb throats if storing for a while.
Oh, and 2 stroke jets don't gum up, they fill with oil and need some cranking to draw fresh fuel through. Not a big deal.

Regards, Andrew.

lsimonson
01-30-2011, 12:09 AM
For the last 10+ years I have been running em dry on my motorcycles, snowblower, and lawn mowers with no problems, and they start right up after sitting for extended periods. Now the gas in the tanks, thats a different problem and it needs to be treated, but I feel good with a "dry" carb when stored. I learned this technique from my flying days. I used to run 2 stroke motorcycles and these were often fuel starved until I could get the the petcock to the reserve position- again no problems.

Bill Huson
01-30-2011, 07:24 AM
Oh my gawd! I have ruined my engine by running it dry every season! Well, maybe it isn't totally ruined since when I runs the carbs dry I'm hosing fog oil in it, which will keep the engine running until I pull the kill cord. And even worse - I only use one can of fog oil and I have *gasp* four carb throats! My poor engine.

Engine in question: 1986 Yamaha 115. Goes through a water impeller every couple years, on it's 3rd under-cowl oil tank sensor, 2nd black box thingy, forgot how many spark plugs, rode hard for a gazzillion hours and put away w/semi-dry carbs, still pumps 130+ lbs compression, and scoots the 18 1/2 runabout along at 52 mph. Would go faster if I jack the engine a notch (+close to 60mph) but then I'd have to buy a new prop, as in 4 or 5 blade cleaver since when jacked the original thick blade Yamaha prop won't hold in a turn - yep, screaming engine and boat jumping around in a quick 180 - FUN!

Canoe
01-30-2011, 07:46 AM
Many, Many years ago we regulary turned our Seagull outboard off by shutting off the fuel before reaching the beach, if we did`nt the carb. would leak through the "Dibbler" and foul-up the boot of the car!r<

Any motor runs lean for only a few seconds ( and revs up slightly ) before running out of fuel and stopping, there is not enough lean running time to create "Hot Spots",Y> if it should run on load for more than 10 mins. ( depending on the running temp. ) you may exspect some damage to the sparkplug and later the piston ( with a 4st. also the valves ).r<

A freshly filled carb. certainly does make starting a lot easyer, my 5hp. Honda ALLWAYS started FIRST pull when cold and did so the 13yrs. I had it.|;) ( I hope my new Yamaha 9.9 does the same ).

The above statements are based on 45yrs. of exsperiance as a Automotive Tech. and Master Mech. but I might be wrong in my judgment but probably not!:d

Alan:ycool:

Canoeyawl
01-30-2011, 11:11 AM
A couple of notes...
Multiple cylinder two-cycle engines can be hurt by running them dry. Generally they will shut down one cylinder at a time, dragging the other/s along without lubrication until it finally stops.
Two-cycle oil has fuel stablizers in the mix, any other additives are not needed.
Fuel stablilizer is a good idea for storage of four-cycle engines. Beware of cheap fuel with alchohol added, it will emulsify water.

Monkey Butler
01-30-2011, 01:54 PM
Oh my gawd! I have ruined my engine by running it dry every season! Well, maybe it isn't totally ruined since when I runs the carbs dry I'm hosing fog oil in it, which will keep the engine running until I pull the kill cord. And even worse - I only use one can of fog oil and I have *gasp* four carb throats! My poor engine.

Engine in question: 1986 Yamaha 115.

Bill, like I said above you can probably get away with this all day long, but there is a better way to lay up your motor.

One nice thing about Yamahas is that they inject the oil directly into the motor behind the carbs without mixing it with the gas first. This is a good system because even if a jet does clog the cylinder still gets lubrication. On any other motor this old I would disconnect the oil injection and run premix but the benefits of the Yamaha system warrants keeping it. I run a 1991 225HP (six carb throats) and I have a 1987 that I keep as a backup. If something catastrophic happens during the season I’ll just swap motors but I still do everything I can to avoid getting into that situation.

I currently have two 200HP Yamahas that I bought at the end of the season because the owner’s couldn’t get them to run correctly. In both cases the problem was fuel system related. I happen to have the carbs from one motor apart on my bench right now so let me offer a visual explanation.

First off, here is a general picture of a Yamaha carb:



http://www.kaufmancatalog.com/images/wbf/1c.jpg


...and here is a side view:


http://www.kaufmancatalog.com/images/wbf/2c.jpg


the carb is "sailing east"; the front of the carb is to the right. At the bottom you can see the float bowl with the big brass main jet front and center and off to the bottom right is the hex/slotted bowl drain screw.

Now here is a shot of the inside of the float bowl removed from the carb:

http://www.kaufmancatalog.com/images/wbf/3c.jpg


On the left you can see the main jet in place and on the right you can see the little channel that Yamaha moulds into the bottom of the bowl to channel every last drop of fuel in the bowl to the drain screw. Here is another shot of the bowl from the side with the jet and drain screw removed:



http://www.kaufmancatalog.com/images/wbf/4c.jpg

You can se that the drain is significantly lower than the jet and the the whole bottom of the bowl is slanted towards the front. If you open the drain screw with the motor tilted every last drop of fuel will exit the carb. If you run the carb dry by cutting off the fuel and letting the motor die you will leave a slug of gas in the bowl which will likely turn to varnish over the winter, or in the case of the new E10 fuels a white-ish gel-goo gas/alchohol/water mix. The two motors I bought at a discount were victims of this. I broke one of the drain screws off and had to drill and tap for a new one; they had never been used.

Keep doing what you are doing. But if you take the time to open the drain screws you will be doing yourself and your motor a favor.

I like to lay up my motor by running them on oil rich premix from a portable 6 gallon tank, 25:1 gas/oil or more. I don't fog but after I shut the motor down I pull the plugs, squirt some straight 2-cycle oil in the bores, crank a few turns to distribute, then drain the carbs.

And with the Yamahas at the beginning of next season I will run 50:1 premix in a portable 6 gallon tank in addition to the oil injection. Do this until you can confirm that the motor is actually injecting oil from the powerhead mounted tank. Sometimes they lose their prime or a blockage occurs in the tank or lines over the winter. It's cheap insurance.

Rational Root
01-31-2011, 07:17 AM
Not sure if it carries over to two-stroke outboards, but running the engine lean is the correct shut-down procedure for piston aircraft, at least four-stroke.

Aircraft engines are a whole other ball game, the get to run on the ground and and at 13000ft, with massively different amounts of O2 available.
I don't know much about the inner workings of Piston engines for aircraft, but I'd be unwilling to assume that what is ok for a Cessna is ok for an outboard.

Anyone who knows about how combustion changes over 13k ft care to comment?

Breakaway
01-31-2011, 08:53 AM
I like to lay up my motor by running them on oil rich premix from a portable 6 gallon tank, 25:1 gas/oil or more. I don't fog but after I shut the motor down I pull the plugs, squirt some straight 2-cycle oil in the bores, crank a few turns to distribute, then drain the carbs.

This is my 'winterization cocktail," and note that I used stabilized fuel and sometimes add a "dash" of fogging oil or Marvel mystery oil to the blend.


Fuel stablilizer is a good idea for storage of four-cycle engines. Beware of cheap fuel with alchohol added, it will emulsify water.

While its is still possible to purchase gas without ethanol(EO) in some places, 99-percent of what's available is E10. And at 3,40 a gallon, it isnt cheap by any means. So, in my opinion, stabilizer should be added all the time, doubling the dose for long-term storage to prevent phase separation--the white gel-goo mentioned above.

Kevin

BarnacleGrim
01-31-2011, 10:23 AM
Aircraft engines are a whole other ball game, the get to run on the ground and and at 13000ft, with massively different amounts of O2 available.
I don't know much about the inner workings of Piston engines for aircraft, but I'd be unwilling to assume that what is ok for a Cessna is ok for an outboard.

Anyone who knows about how combustion changes over 13k ft care to comment?
The mixture is leaned at cruise altitude, typically to a few degrees rich of peak exhaust gas temperature.

I think the problem is that once a 2-stroke engine loses its supply of fuel it also loses its lubrication. The question is how much damage it causes.

Dagnauts
02-01-2011, 10:56 AM
The owners manual for my 1972 Mercury 7.5 recommends running the motor out of fuel before storing.

Rob Stokes, N. Vancouver
02-06-2011, 07:41 PM
Oh my gawd! I have ruined my engine by running it dry every season! Well, maybe it isn't totally ruined since when I runs the carbs dry I'm hosing fog oil in it, which will keep the engine running until I pull the kill cord. And even worse - I only use one can of fog oil and I have *gasp* four carb throats! My poor engine.


and some wonder why there are not more folks posting.....

Bruce Hooke
02-06-2011, 09:04 PM
You know how outboards loose power when repeatedly stored for a few weeks between uses? Well here is why and how to prevent it. This trick is not for long term - over the winter- type storage which should be done differently.[/URL]

A lot of responders on this thread seem to be overlooking the "NOT" in the last sentence above. The OP is talking about "a few weeks between uses" NOT preparing the motor for storage over the winter.

Phil Y
02-07-2011, 02:36 AM
A lot of posts seem to be about airplanes? Who cares what the original topic was???