2-cycle engines hate me!! !

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Okay, this past week, I have been trying to clean up my yard from all the storm debris that Hurrican Irene as thrown around. This has involved running a chain saw, leaf blower, weed eater, and other tools that have small 2-cycle engines on them. Granted, these tools are awful to run in their own right, as they are noisy, smelly, and vibrate some kinda bad, the other half of this is I cannot seem to keep the #^&#! !! ! things running! I have made all attempts to make sure I run the old gasoline out of them before I put them away and use sta-bil in the gas. I also am very meticulous to make sure the fuel and oil is mixed perfectly. My maintenance efforts work great for bigger engine stuff like my lawnmower, and my boat engine, but my small power tools are impervious to any type of care, and will break down anyways!

My chainsaw ran good for about an hour when trying to cut up a fallen tree limb, then it quit. I disassembled it and found a bad fuel line. I replaced it, the fuel filter, then disassembled and cleaned the carburator. The saw should run perfect, but it doesn't...won't run under load. My weed eater has been acting the same way. I gotta keep a screwdriver with me all the time to tweak the carburator. One setting will get it started, but then I must adjust the fuel mixture set screws in to get the tool to run with any kind of power. My leaf blower does the same thing....ANNOYING!! !!

how do professionals use these things everyday? I see lawn care people buzzing around my office with all sorts of power tools, and they run perfect! What is their secret!

They use their machines every day so they don't have time to rust up and for fuel to go waxy and horrible.

2-cycle engines sould be banned they pollute alot more and are halfass tech than a properly sealed gas only engine. Or even better get a long eletric power cord and use an eletric lawn mower, leaf blower, and chainsaw :o

2 cycle engines need synthetic oil with a 100 to 1 mix ratio.

You might have a mechanical problem with the carb. It also might be plugged as in passages, and/or your air filter is plugged, and/or spark plug is fouled.
Do you remix your gas, as shake the container every time you fill up? The oil will stratify if you don't.

I have an 18 inch chainsaw, and weed wacker. I use a synthetic 2 cycle oil in my mix that is good for any ratio from 36 / 45 to 1. It's very simple. It's universal. It doesn't foul the spark plugs, and plug the muffler. The stuff doesn't smoke as badly either.

At the end of every year, I pour unused 2 cycle gas into the gas tank in my truck. I don't use "stabil" to get me through the winter to the next season. I've been running my weed wacker for 9 years this way without any problems.

There is also a version of sta-bil for ethanol fuel--are you using the right one?

We find that electrics work great for small tools--though we certainly appreciate the power gas provides for our lawnmower and 2 stage snowblower. We have never used sta-bil ourselves--we just siphon the gas back into a plastic gas can and run the engine dry--has worked well for a decade.

Are you using ethanol-free gas?

Ethanol is poison to most any engine. It's only in 4-stroke motors that ethanol is fairly safe because they design the fuel system with ethanol in mind...and even those can be damaged if the QC checks fail and there is more than 10% ethanol in the gas you are getting.

2-strokes DO NOT like ethanol. It damages the rubber parts which are pulled from stock not formulated to handle the ethanol.

http://fuelschool.blogspot.com/2009/02/ethanolgasohol-problems-with-2-cycle.html

This blog suggests using synthetic lubricant when using ethanol fuel with 2 stroke engines. Though that would only fix the lubrication problem.

Try cleaning the jets in the carb, if they are accessible. Just make sure you note down how everything is put together before taking it apart.

If ethanol is an issue, you can buy premixed gas+oil with no ethanol at Walmart.

A simple test For both units:
Take the fuel bowls off of both carbs. It either unscrews itself or there is a holding screw through the bottom of bowl . And now make sure carb is upright for this test.
- 1) Now blow into the fuel line going into carb with your mouth. It should allow air in through it.
- -2) now raise the float with one hand and blow again; it should seal it off by keeping the float up against the needle seat.

If this fails as allowing in air,( with float up ) then you are flooding with gas. Take the needle seat out and now take aerosol cleaner with straw to clean passage. Re-test.

If float passes this shut off test in 2; check to see if float is gas logged. What I mean is the float is supposed to float in the fuel bowl ; if it has a hole in it, the fuel will enter into the float and it will sink. If it sinks then fuel will always enter carb. thus flooding the engine. It will still run but you will always be tweaking the mixture as you are doing. It will run rough.

To see if the float floats, take it out and submerged it in a little gas, wait an hour and float should not sink.

These two ^ are most probable.

My walk behind mower has a 6.5 HP tecumseh motor and I troubleshooted it this way. Once a plugged needle valve seat, and a hole in float at another time.

I'm guessing by using stabil you didn't gel the innards of the fuel passages, i.e. main jet. And you said you ran it dry on seasons end.

If the fuel bowl test passes, take the "jet" out of the bottom of the carb. It's brass colored and has a standard slot in it for screw driver.
Take aerosol cleaner( brake cleaner works) and blow up through bottom where jet was. take compressed air and blow through.

2 cycles are easy in that it always comes down to spark or gas. You got spark, then it is fuel related. No valve timing in two strokes.

I recently got a Suzuki GS 450 running ( a 4 stroke motor cycle). It eventually came down to bad gas and plugged needle seats in carb.

You don't mention the spark plug.

I had two stroke motorbikes as a youngster.
The plugs were always oiling up.
We always carried a few spare ones with us.

Take your plug out and get it sand blasted.
Better still buy a couple of new ones.

Yep, always the first thing to check with a two stroke. They get black and oily, clean them with a fine copper brush. A regap wont hurt either.

Also most two stroke equipment (especially chainsaws) will only start from cold when held in a certain position.

You wouldn't want to carry a 4-stroke weed eater or chainsaw, and electric ones tend to be weaker and less practical due to the chord length and it getting in the way. 2-strokes remain on the market because they are small, light, and simple.

If there is anything you haven't thoroughly cleaned out inside or outside it and if there are any replaceable parts like spark plugs, air filters, oil filter, fuel filters, or anything else, change those out too and clean their fixture as well. You could try going to the auto parts store and getting some carburetor cleaner to mix in your gas once you get it going. If you are using pre-mix engines check that any additive cleaners are compatible.

Or you could waste money on snake oil to see if that works...

If petrol/gas wont clear a blockage/buildup, i doubt the various additives you can buy will. Just clean the carb yourself. Also have you tried "easystart", it comes in an aerosol can. You just spray it in the air filter and then turn the engine. Used to work a treat on my DT125 on a cold morning.