Small gas engine dies when choke full open

This is a tell tale sign of a lean fuel mixture. By choking the unit you are manually creating a richer fuel mixture. I would purchase a compression tester from a local parts store and check compression. If that's ok, I'm willing to bet the problem is still carb related. Two stroke carbs are tricky to clean because of high/low ports that are one way and sometimes impossible to clean. Did you remove high and low needles when cleaning carb? Another trick is to mix seafoam with your gas, then mix two cycle oil to proper ratio. Use 2 ounces seafoam to one gallon of gas, then mix two cycle oil to proper mix. Hope this helps! Good luck and happy wrenching!

I’m happy to assist further over the phone at https://www.6ya.com/expert/layne_0fccff498c319c32

Many times with a gas mix, after sitting for a while, the mix separates and gums up the carb. Taking the carb off and soaking it overnight in a parts or carb cleaner and running carb cleaner through the tank and gas lines will cure this.

Start with the choke on full press the fuel siphon button till the lines are full of fuel. pull handle until it tries to start but stops. move the choke to half then start again. let it run for 60 seconds on full. don't move the choke to full or it will stop. Either slow the revs and then put the choke on full or keep the revs high and slowly move the choke to full (to allow the governor to slowly advance with the new revs)

You probably have a bad hose or a bad hose connection that is sucking mostly air instead of delivering full fuel to the carburetor!

First, you need to dump all of the fuel out of the gas tank, Preferrably into a gas container. If you know how much oil you dumped in, you can calculate how much more gas to add. You could also just dump the gas, re-mix some new gas and oil, whichever you prefer.

If you are comfortable doing this, remove the fuel lines going to the carberator and let them drain into a pan. Pump the fuel primer to purge the gas out of the carburator, and then re-install the fuel lines. This might help you get it started a little faster, but its not necessary. You can burn the old gas in the engine at it will be fine.

Next, remove and replace the spark plug. Its probably fowled out with too much oil. Keep a can of carb cleaner and a small wire brush handy, you may need to clean the spark plug a couple times. If it gets too dirty, you can replace the spark plug with a new one. Do not burn Carb Cleaner in your engine for long periods of time, it will damage the engine.

After you have installed the spark plug and put some correctly mixed gas in the tank, Try to start the engine again. There will be some residual fuel in the fuel lines going to the carberator, so you will need to burn off that gas.

If you can't get it to start, try these steps:
Choke off, throttle wide open, crank several times. (or let it sit in the sun for a couple hours) (this corrects flooding)
Prime carberatur, Choke full on, throddle idle position, crank until it fires once but does not start.
Choke half, crank until it fires again or starts.
If it starts skip this step: (Choke off, crank until it starts).
Keep the choke on half for about 10 seconds and let it idle.
Put the choke off and let the engine warm up for a couple minutes.
After warmup, test the throttle to see if it will run at full throttle (it may take some fluttering until the engine is fully warmed up)

Let the engine run at full throttle for a few minutes. The exhaust may be a little more blue-smokey than normal...this is the excess oil burning...totally normal and harmless.

If you removed the fuel lines from the primer bulb you may have reversed the lines. On two stroke engines the primer pulls gas through the carb it does not push gas into the carb. On the back of the primer bulb there are two hose barbs, one says in (in very small letters) this side goes to the carburetor and the other goes to your gas tank (it is a return line) This line is about a third to a half way up the side of your gas tank, not at the bottom where the fuel line is.

If the trimmer is more than 3 to 4 years old, you may want to replace the carburetor parts, (new carb. kit). It also depend on the amount of use.
If it is newer than that, then you will need to disassemble the carb. and spray with carb. cleaner. Make sure that the small screen in the carb. is free of debris. Use a Den tek Brush,
(http://www.drugstore.com/products/prod.asp?pid=165357&catid=1152), to clean the small portals in carb. Reassemble and start.
If you need further assistance, just let me know.

Jim

The fuel cap has a rubber air bleed valve to allow air into the tank during running. My blower ran for about 5mins, then slowed down and stopped. When I opened the fuel cap, you can hear an air rush, indicating low pressure in the tank which starves the engine of fuel. Problem was solved by clearing the blockage in the cap.

check the fuek lines for hole and leaks, check the fuel filter and clean if necessary. remove the carbuerator and inspect the gasket; it should be soft and flexible, if it seems hard or brittle replace it. clean the carb with carb cleaner sray (available at any local auto parts store) and compressed air. make sure you get inside the small fuel rail holes. if that doesn't work have the carb repaired at a service center or replaced.

That fuel/oil mix ratio should be 32to1 or 32 ounces gasoline to 1 ounce oil. You will have to make up a new mix and probably clean the fuel system and the spark plug before it will start.