Short term storage, empty carbs?

[dngharvey]

Our 115 two stroke gets stored twice a year for three months and then two months. I've been in the habit of running the carbs dry after adding stor n start to prevent ethanol issues.
Someone recently said I'm destroying the cylinders because of no oil protection when fuel runs dry. Now I'm perplexed, non ethanol is not available in my home area but is in Florida where we winter.
What do others do?

[99yam40]

running a motor until the motor dies does not remove all of the fuel from the carb bowls. some remains in them and evaporates leaving layer of residue.
some of the carbs run out of enough fuel to fire those cylinders before the rest of them so you are running some with out fuel and oil. upper carbs run out before the lower ones due to gravity and where the last of fuel is located in the lines.
Plus you still have some fuel in pump and lines.
best to drain the carb bowls if you do not have the ability to start the motor often enough to get fresh fuel filled up in the system to keep it from drying out.
My thoughts on the subject anyway.

I thought Store and start was an additive for oil in 4 strokes. Did not know they made it for gas in 2 strokes

[boscoe99]

Without knowing exactly what model motor you have, most Yam two strokes of 115 HP have an oil injection system. Oil is not provided via the carburetors since oil is not mixed with the gasoline. Running the motor dry would have no effect whatsoever on oil getting to the motor. You have been listening to someone that does not know his ass from a hot rock about Yamaha motors.

If a motor is stored long term it is probably best to drain each carburetor float bowl using a screw that is provided just for that very function. Just don't be hamhanded with the screw driver. Those are delicate screws.

Now on the other hand, if what you have been doing in the past works successfully for you then it is hard to argue against success. I would just keep doing what you have been doing. If it ain't broke don't be looking for a fix.

[scofflaw]

I store for 6 months at a time and use the run dry method, but will start spraying fogging oil into the carbs as it is running out of fuel. Never touched the carb drains, been doing this for years with no issue

[99yam40]

Without knowing exactly what model motor you have, most Yam two strokes of 115 HP have an oil injection system. Oil is not provided via the carburetors since oil is not mixed with the gasoline. Running the motor dry would have no effect whatsoever on oil getting to the motor. You have been listening to someone that does not know his ass from a hot rock about Yamaha motors.

Exactly how dose the oil get into the cylinders if not carried with the fuel thru the crankcase into the cylinders themselves?
I am fairly sure it is not injected into the cylinder on these motors, thought it was injected into the intake /reeds.

I would think that small of a volume of oil would not seem to carry well thru the crankcase without the volume of gas going with it and spreading it around the parts that need lubrication.

I just gots to know

[scofflaw]

Would have to agree with you on that. I'm sure the residual oil, coating the parts, is not going to disappear either, with no gas flushing it out. Runs for less than 30 seconds until all cylinders shut down. Doing it like this for 40 plus years, never had a problem.

[DennisG01]

Since using a stabilizer (I use Startron), I have stopped running things dry. This includes larger motors, motorcycles, even tiny ones like weedwhackers, mowers, chainsaws, snowblowers, etc. It's probably been 10+ years since I've run anything dry. I'm not saying this to start a discussion on whether one way is better than the other - just offering some real life experience to another option. I will say, though, that I am very religious about using the Startron (all year long) and I never skimp on the ratio/amount I use. In the Yamaha, I also use RingFree Plus, but I don't think that has anything to do with gas stabilization for extended storage.

I'm also a believer in fogging an engine for extended periods. Whether it's truly needed with a 2-stroke (because of the oil in the gas), or not, I don't care. It takes next to no time to do it and, if anything, it can only be "better" than not using it.

[ausnoelm]

I kind of don't think a couple of months is "long term" or considered "storage" millions of boats sit in driveways for way longer than that without doing a thing, and work OK when cleaned out of leaves and spiders for an outing!

[dngharvey]

Our 115 two stroke gets stored twice a year for three months and then two months. I've been in the habit of running the carbs dry after adding stor n start to prevent ethanol issues.
Someone recently said I'm destroying the cylinders because of no oil protection when fuel runs dry. Now I'm perplexed, non ethanol is not available in my home area but is in Florida where we winter.
What do others do?

I use "Stabil" which according to the label is good for two and four stroke.
This 115 has been trouble free but have had issues previous with both a 70 and a 90 Yammie getting going good after lay up.
Think I'll try the carb drains next, should it be run dry and then drained?

[DennisG01]

Make sure you are using the greenish-colored Stabil when using ethanol fuel. The red stuff does nothing to combat ethanol issues. The greenish stuff can be used with non-ethanol fuel, too.

[99yam40]

the problem I see with carbed motors is the carb bowls are vented to atmosphere letting the fuel to evaporate out the vent leaving some sticky stuff behind gumming things up.
but that is mainly with premix motors, not oil injected, or FI ,or 4 stroke motors

The 2 strokes my brother and I have run have all been pre mix, so have not had to open up any of those other motors.

I prefer to stabilize the fuel and keep the carb bowl full.
even if you do not run them often, you can still pump the bulb to fill the bowl back up from time to time to replace what has evaporated out, if you store at your normal residence.

I just do not like the idea of running some cylinders lean or without fuel to them while the others are still turning the motor

[99yam40]

I use "Stabil" which according to the label is good for two and four stroke.
This 115 has been trouble free but have had issues previous with both a 70 and a 90 Yammie getting going good after lay up.
Think I'll try the carb drains next, should it be run dry and then drained?

no need to run until it dies if draining the fuel out of them

[boscoe99]

Exactly how does the oil get into the cylinders if not carried with the fuel thru the crankcase into the cylinders themselves?
I am fairly sure it is not injected into the cylinder on these motors, thought it was injected into the intake /reeds.

I would think that small of a volume of oil would not seem to carry well thru the crankcase without the volume of gas going with it and spreading it around the parts that need lubrication.

I just gots to know

The area behind the carburetors is low pressure air relative to atmospheric pressure. The oil pump raises the pressure of the oil to above atmospheric pressure.

High pressure oil is pumped right behind the carburetors into the intake manifold where it gets picked up by air flowing through the carburetors. That air of course has gasoline fumes in it based on the carburetors doing their job of turning liquid gasoline into fuel vapors and mixing those vapors with normal air. The gaseous air/fuel mix, now with oil added to it, gets sucked into the crank case. From there the oil gets slung around and does whatever lubricating that it is supposed to be doing.

[boscoe99]

You now have me thinking about the dynamics of a liquid homogenized mixture of gasoline and oil (50/1 ratio) flowing through a carburetor and how the gasoline must vaporize into a gaseous state to combine with the air while the oil is left behind in a liquid form.

[pstephens46]

Not sure if "left behind" is the right way to describe it. Some does get left behind and some oil is burned. Some engineer, somewhere, has an idea how much of each is occurring. Determining mix, etc. Other variables are in play as well.