Is there danger in running out of fuel WOT?

[russhd1997]

All of my saws except my MS290 give me some kind of warning before they run out of fuel. The MS290 just dies. I like to shut the saw off at the 1st sign that it is running out of fuel so that it doesn't take as many pulls to restart after fill up. I also don't want to damage anything internal because of it running too lean.

 

[Fish]

Yes, participating in behavior that will damage your saw, I.E. running lean until it screams then dies, is a "GOOD" idea!!!!!

 

[Fish]

OK, so leaning a saw out until it dies is OK???

No damage???

It is all about the damage baby.....

 

[blsnelling]

Hey Fish, tell us how y ou really feel:msp_biggrin:

 

[Bomber]

HUH????

Whatcha smokin?

I have yet to see a two cycle, or any motor, continue to run without fuel. When you are at WOT and the fuel/oil supply runs low it will sputter. The fuel/oil does not instantly stop when the motor is running. At this time fuel is being mixed with air in the fuel line causing the RPM's to decrease. If you continue to pull the throttle when the obvious signs of running out of fuel/oil exist then you will run the motor lean. Most operators stop prior to this occurance.
Do you pre oil your cylinder prior to starting a saw?

 

[blsnelling]

Do you pre oil your cylinder prior to starting a saw?

The oil's still there from when it was last running.

 

[TK]

I drink a 6 pack every night, but I don't get drunk. Will my liver be OK?????

 

[Bomber]

The oil's still there from when it was last running.

Just like it is still there when you run out of fuel

 

[komatsuvarna]

I have yet to see a two cycle, or any motor, continue to run without fuel. When you are at WOT and the fuel/oil supply runs low it will sputter. The fuel/oil does not instantly stop when the motor is running. At this time fuel is being mixed with air in the fuel line causing the RPM's to decrease. If you continue to pull the throttle when the obvious signs of running out of fuel/oil exist then you will run the motor lean. Most operators stop prior to this occurance.
Do you pre oil your cylinder prior to starting a saw?

Well they won't run without fuel, but Ive had several older saws that will go really lean when its about out of fuel. I guess its getting just enough fuel to let it run, but not enough fuel for the amount of air entering, and still make a couple cuts with it before it runs completely out and dies. I know all of them don't do this, but Ive worked on 3 in the last couple of months that has.

I try to fill mine up before it runs out....

 

[blsnelling]

Lean is what happens when there's too much air for the amount of fuel that's present. It's impossible not to go lean when you run out of fuel at WOT.

 

[TK]

LOL!!!

You're at WOT meaning you're getting all the air you could ask for every revolution. But you're running out of gas, probably pulling air bubbles up the fuel line. So now you're getting more air than fuel in the mixture. Kinda like you just screwed in the H jet. So here we are with a lean condition. Now you're probably not going to toast a saw all at once doing this. But you are wearing it away. Heat breaks down lubrication properties. Bingo, you just broke down the oil for this round and caused extra wear. Add gas and you're back in business. Then you do it again, a little more extra wear. Over and over and you just prematurely wore out your saw. But the thing that will get ya is that you won't have a lean seizure, just a premature loss of compression that will just look like normal wear. So you won't blame it on anything that you did, it just wore out. But that's just it, you could still be cutting wood just fine but are too oblivious to realize that it actually is your fault. Now you're replacing rings instead of cutting. Ignorance is bliss.

 

[fearofpavement]

Wow, I'm not sure I am understanding what I am reading. Are you posters indicating that by running the saw out of fuel you are likely to damage the engine? If so I strongly disagree. If you go by that theory, then what do you do when you are adjusting the H screw? Is that likely to ruin the engine too?

I think we need to discuss proper fuel/oil mix ratios as soon as this topic plays out.

There are two times I fuel a saw. One is when I start using it for the day. The other is when it runs out of fuel. I have never stopped and refueled with the tank partially full unless I needed to sharpen the chain or take a break for another reason. And amazingly I have never had an engine failure. I think this is all "theory" with no empirical evidence to back any of it up.

 

[Fish]

Any new saw, with a fully adjustable carb, can be fully melted down by by someone playing with the carb/adjustments while running.

So it makes sense, that if there are no adjustments, it could still happen too.

But a saw running out of fuel, it is not unreasonable to assume saw damage will result......


But WTF???? Has this forum been absorbed by MORONS????

 

[Fish]

Back in the early Nineties, at the Stihl schools, they would take a new saw and melt down by futzing with the carb, which is incredibly easy to
do. We would tear it down, but it can easily be redone by a moron with a small screwdriver on any new saw.

 

[PogoInTheWoods]

The oil's still there from when it was last running.

To what extent/quantity (if present at all) would certainly be a matter of any number of variables when the saw shut down -- presumably for the sake of this discussion -- due to lack of mix.

If it was already a borderline white hot lean condition when it ran outta fuel, there may not be much more than aluminum x-fer left in the cylinder -- along with the remaining mix still there from when it actually shut down -- not from when it was last running.Two different conditions altogether....

Poge

 

[blsnelling]

Wow, I'm not sure I am understanding what I am reading. Are you posters indicating that by running the saw out of fuel you are likely to damage the engine? If so I strongly disagree. If you go by that theory, then what do you do when you are adjusting the H screw? Is that likely to ruin the engine too?

Seriously? Go ahead and screw your H screw in and see long it runs before seizing.

 

[fearofpavement]

Seriously? Go ahead and screw your H screw in and see long it runs before seizing.

I am not talking about making and keeping a lean adjustment, I am talking about the lean/rich ranges that one goes through while tuning for a brief moment. I am making a correlation with that to the "brief moment" that the saw is lean while it is running out of fuel.

 

[Jed1124]

You guys are arguing with Stihl mechanics and saw builders. They said it's not a good idea. They get paid to build and fix saws. Running a saw out of gas at idle before storage is ok. Racing it at wide open throttle till it dies is not ok. I will take them at their word. They know what they are talking about.

 

[blsnelling]

I am not talking about making and keeping a lean adjustment, I am talking about the lean/rich ranges that one goes through while tuning for a brief moment. I am making a correlation with that to the "brief moment" that the saw is lean while it is running out of fuel.

Gotcha.

 

[WidowMaker1]

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