OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Trimmers and Brushcutters Two Stroke Trimmers & Brushcutters How do you clear a badly flooded engine?

i ask this because i've got at least a couple of whipper snippers in this state. They have sat with petrol/oil in them for years consequently the engines are flooded and the pull cords are difficult to pull. What is the quickest way to clear the residue from the engine. Tried a degreaser but havent notiiced much difference.

Take the plug out, pull the cord a lot 20-30 times till no more spray comes out of the plug hole, if it's oily residue pour some fuel down the plug hole and pull cord slowly for the fuel to go down into the crankcase and then repeat, pulling quickly alot, 20-30 times if needed.
Do the above with the ignition switch in the off postion so as you don't get spark from the lead and ultimately start a fire.
Dry the plug and replace, do not prime, and follow the start procedure with no choke.

I'd depart just slightly from bigted's method, though the principles are the same. First, I'd begin by draining the fuel tank, and if it has an air purge system, I'd drain the carburetor by using that. Then after the multiple starter pulls with the spark plug out, I'd put a couple of spoonfuls of mixed 2 stroke fuel into the cylinder or the carburetor air intake, rather than putting straight petrol in. The reason for this difference is that I've seen people use straight petrol either repeatedly or in excessive quantity, and the result has been dry, squeaky, partly seized piston rings when pulling the engine over. Standard 25:1 or 50:1 mix will readily pick up both petrol and oil from the crankcase, and will do the clearing job very well.

After the fuel-clearing exercise, before putting fuel in the tank and trying to start it, I'd test the spark carefully. Chances are you will at a minimum have to wash and then scrape the spark plug to get it firing properly. It's possible though that the plug will have to be replaced.

Thanks Ted and Grumpy. Working the petrol into the crankcase seems to be the key. Still a bit difficult to use in no choke but arm doesn't hurt as much now. Much appreciated and wish I'd asked before taking to the degreaser.

Left the trimmer for a few days hoping there might be some evaporation, I tried the trimmer tonight it was as difficult as it was before, the compression gauge records 120 psi.