I know you guys can help me fix my chainsaw.

[Toyboy]

Leaded? No such thing, anymore.

I believe he meant E free.

 

[Jim Nelson]

Leaded? No such thing, anymore.

I was told by a friend who is a pilot that the aviation gas is low lead 100 octane.I'm really tempted to try some in my chain saw since it's only around $6.50 a gallon compared to $23 I'm paying at the equipment store for 94 octane non ethanol.

 

[LD1]

For the filter hose and filter, I have found the best tool to be them fish-hook extractor pliers. like these http://www.cabelas.com/product/Fish...y/Pliers-Grippers-Hook-Removers/104505480.uts

 

[Gary Fowler]

If it cranks and idles fine but will only run half RPM at full throttle, that is exactly what my weedeater was doing and cleaning the carbon out of the muffler solved the problem. I would check that again before anything else other than fresh gas.

As a reply to how long it take gas to go bad, I had left some untreated (no Stabil) in my lawnmower one time and it refused to even attempt to start. I took off the tank, dumped the gas on my gravel driveway with intent to burn it off. It wouldn't burn by throwing a match on it. I finally got it to start burning by heating with a propane torch but it smoked like burning rubber. That was only 4 month old gas. I cant believe 8 year old ethanol gas would be anything but varnish. Perhaps it was pure gas which will last a lot longer than E gas.

 

[Oaktree]

I generally mix up a gallon of gas at a time, depending on how much I use the saw it can go 6-8 mo. before I use it up. Never had a problem with gas of that age.

One other thing to check that no one's mentioned yet...the carburetor. My (Echo) saw started running rough, no power. None of the usual tricks helped. Finally pulled the carb off...it had a bunch of sawdust in it! Cleaned it out good, and she was back to running fine.

 

[eddie48]

When I have had 2cy engines that ran as you describe, I have opened (lefty loosey) the high speed jet screw about 1/4 -1/2 turn. After a little while using the engine I usually have to turn it back in to where it was. Seems like something gunks up the orifice that the adj. screw seats on but it cleans out when you give it room and run it for a while.

 

[Sodo]

Good point, that's making the assumption that it needs a little more gas to get the juices flowing (cleared out) then set back to normal. Makes sense that first "opening the needle valve" can allow some blockage to pass thru, after which it needs to be returned to the correct mixture adjustment.

Some carburetors have plastic "limiters" on the mixture screws that prevent you from making a full turn. This is to prevent monkeying with the mixture, which is what we are discussing. In this case you may not be able to do the trick below unless you remove the limiters. Or decline monkeying.

==========

There's also the method of running the screws down to their seat, and then backing out again (to re-enforce the original settings). Sometimes a very small 'growth' of some crap occurs near the valve seat, partially blocking it thus changing the flowrate to a leaner condition. Running the screw in to the seat (lightly) then back out the same number of turns can crush this crap buildup and re-establish the last (presumably correct) setting.

You should be counting the number of turns in so you know how many to come back out. I prefer to count in half-turns.

I think the fact that nobody knows these little tricks (and others) anymore is a large part of the reason "ethanol gas" becomes the catchphrase for many small engine problems. Agreed there are actual ethanol problems which others seem to have (but I haven't in the fifty or so engines that I have).

 

[kenmac]

You guys talk about running 50:1 fuel mix... I've been running 80:1 - 100:1 for yrs in all my 2 cycle equipment

 

[N80]

I have not had a chance to mess with the saw since my last post but remember that this saw is like new. It has been around for a while but used only a handful of time. Don't see how it could be carbon build up. Could be old gas but I just don't see it. I have lawn mowers, a Stihl string trimmer and a Stihl saw that have been running for ten years or more with cheap ethanol gas that sits in them for 6-12 months.

However, there appears to be a filter looking thing on a small hose _outside_ the fuel tank. Is this a breather for the tank? If so maybe it needs cleaning out. Could probably test this by cranking with the fuel cap loose or off.

 

[N80]

I knew you guys could help me fix my chainsaw. It was the fuel filter. Fished it out and it looked like new (since it is new). Blew it out with the air compressor, stuck it back in and everything works fine. Not sure what the issue was. Maybe varnish or smutz from the old gas. The manual also recommended cleaning the spark arrestor screen but it was clean. The manual also shows how to get carbon deposits off piston and exhaust port which I thought was interesting.

Anyway, thanks for the help. I know when I have a DIY or mechanical question the TBN folks get me straight every time.