Fuel Issues?

[MNBobcat]

I have a Dolmar saw with only about 5 tanks of fuel through it.  I had some problems where it would idle fine but when cutting it would bog down and act like it was starving for fuel.  It would do the same revving it when not under load.

It started right after adding new fuel (from a new can) to it.  So I assumed a fuel issue.

I dumped all the fuel out of the tank.  Got a new can, new oil and went and got new fuel.  I refilled the saw.  It ran great so I figured I had bad fuel in the original can.

I came back about 1 1/2 weeks later and the saw ran good.  It ran out of fuel.  I poured in the fuel that had worked well 1 1/2 weeks ago.  But it had been sitting in an unheated outdoor shed with no cap on the fuel pour spout.  The same problem occurred right after I added the fuel from the plastic fuel can.

I find it difficult to believe the fuel absorbed enough water in 1 1/2 weeks to cause problems again.  Any thoughts?  Just a coincidence?

[DDW_OR]

are you using ethanol free fuel?

ethanol will grab water from the air
90% of chainsaw users use ethanol free fuel
the other 10% have troubles  :D ;D

[MNBobcat]

!  The first can I had problems with was ethanol free.  In checking into it with the local saw shop, they told me they had seen problems with the ethanol free fuel because a lot of stations don't sell enough of it to keep it fresh. 

So the second can, the one I used today, was high octane but not ethanol free.  It was exposed to temperature swings over the last 1 1/2 weeks.  Also, that particular plastic can didn't have a cap for the spout so it was open to air.

I could, tomorrow, try dumping the fuel out of the chain saw and then refilling it from the same gas can but use my Mr Funnel to make sure no water gets into the fuel in the saw.  I guess that would confirm if its a water issue.  Otherwise, it may be some kind of mechanical issue.  Its just odd that the saw ran good until I poured fuel in from the can.

[starmac]

Are you saying that a saw shop advised you to use ethanol??
Where are you located that the ethanol free does not sell well??

[thecfarm]

I use my fuel kinda fast. I use the highest grade of gas I can get at my local gas station. I use to get gas from one place that I have been going to for years. I went on lunch and they had the pumps down due to shift change. So I went up the road. Truck was just about on empty.Truck seem to run better?? Was skipping and might stall at a stop sign once in a while. Went back to the same old place,truck not running the best again. So I went up the road and have not been back to the other place. Truck runs fine now.  ??? All gas is not created equal.  ;D

[Al_Smith]

What's this 90% use ethanol free  fuel business ? Where did that come from? Truth be known it's probably the other way around .
Why think about that a minute .Only a very few would go out of their  way to hunt down ethanol free gasoline to run a chainsaw which truth be known run on blended gasoline just fine .
Maybe I'm just lucky because I've never had a problem with it at all .Ah yes the great gasoline debate to go down as the next great topic of conversation next to the oil wars . 8)

[ZeroJunk]

Supposedly, the ethanol if left in a container that is not completely sealed will pull water out of the humidity in the air. The pockets of ethanol/water supposedly will not mix with oil.

The tree work guys around here as well as the landscape guys come in the store every morning and buy plain old ethanol fuel. I think the key is that they use it right then.

I would not buy ethanol gas for 2 cycle equipment and let it sit for six months, or even a few weeks if you have lost the cap on your can or something.

As far as the saw in question the first thing I would do is richen up the carb adjustment. If it is already against the limiter lose the limiter.

[MNBobcat]

They didn't say to use fuel with ethanol in it they just said they had seen a number of saws come in that the problem was due to non-ethanol fuel that wasn't fresh.

Are you saying that a saw shop advised you to use ethanol??
Where are you located that the ethanol free does not sell well??

[John Mc]

No idea if this caused your problem or not, but find a cap for your jug or get a new one. Some of the components in gas evaporate off more readily than others. Gas stored in an unsealed container will see this happen at a greatly accelerated rate. What is left generally does not burn as well as fresh gas. You need to be storing it in a sealed container.

[MNBobcat]

I poured the fuel out then refilled using my Mr Funnel so I know there is no water in the fuel.  Ran fine until it got hot so now I'm thinking it might be the coil.  I bought the saw on April 8th of this year so its still under warranty.  Going to take it to the dealer tomorrow and let them sort it out. 

Thanks for all the suggestions/advice!

[John Mc]

I poured the fuel out then refilled using my Mr Funnel so I know there is no water in the fuel.  Ran fine until it got hot so now I'm thinking it might be the coil.  I bought the saw on April 8th of this year so its still under warranty.  Going to take it to the dealer tomorrow and let them sort it out. 

There are more to fuel issues than just whether there is water in it. However, if it's still under warranty, it's certainly worth asking the dealer to take a look. If it were me, I'd be inclined to try a fresh tank of gas first.

[Al_Smith]

I'd have to second that .If it's a new saw it appears something is wrong with it .I complained when they went to lead free gas because I had a high compression Olds Toronado that would not shut off but I've never had a problem when they stuck ethanol in the gas nor have I had a fuel line freeze up because it got water in it .
Yeah maybe with some of the old chainsaws I have the seals go bad and the carbs need rebuilt every 5 years but they are old .The newer components are more robust to alcohol than 40 year old stuff so it is getting addressed .Face the music,ethanol is not going away .--or you can  run hither and yon buying aviation gas as if that's going to do any good .The gas wars,gotta luv it  ;D