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two cycle engine on a small tiller wont start. It has new gas, new oil, a clean spark plug. What else can I check? Answered




2 months ago

Ethanol in gas is bad. Here's how to remove it. Go to WallyMart and get an empty 5-gallon clear plastic jug. Go to gas station w/gas can and get say 2 gallons of PREMIUM gas. Pour gas into clear 5 gal jug. Add 16 ozs or so of water. Shake shake shake shake and then some more. Let it settle. The ethanol will now be combined with the water and is easily seen. Siphon out the fuel into a fuel can. Discard the H2o/alcohol mix. Can only help small engines.

used mine once for several hours. 2nd time I used it, it lost power and would not restart. Removed the cylinder and as suspected piston was ruined. This tiller was a replacement for the same problem. Carb seems to be too lean. I was on the original mixture of premix using the oil provided.

I'm just looking for some advice distiller does it come with a spark plug it doesn't come with a choke y mean a plunger has a manual toggle switch on and off by the havitamins to clean up the do I need to take some vitamins to clean up the carburetor the fuel line doesn't seem that bad the fuel tank was clean just looking for some kind of guideline to go


having worked at a small engine dealership for 6 years. the most common thing with tillers is that they only get used about once a year. So you have gas (which might be fresh when you first add it) sit in the unit for a full year (people say if your gas is older than 3 months, get rid of it) and likely goes bad and gums up the carb. I am thinking you will likely have to clean the carb and rebuild it with new gaskets, diaphragms and needle. You may be able to take it to a local small engine repair shop and get it cleaned and rebuilt for about $50 (including parts). You may also want to check the condition of your fuel lines and fuel filter. Let us know how it works out.


5 years ago

In addition to what Josehf said you could also have some water in the gas. Even though you put new gas in, water sinks to the bottom so if you try and start it you are getting water along with some gas. If it has rained on the machine or even just from condensation it can happen. It used to happen to my big tiller all the time. If you can get to the fuel line that comes out of the tank easily you can take the line off and drain the gas tank into a glass jar. If it has water in it you will see little globs of it on the bottom. Be really careful if you do this. You will spill gas so make sure there are no sparks and do it outside where the fumes will dissipate. Once you get the water out you need to pull the start cord enough times to get the last water out of the corroborator. Then it should run OK. I used to put a plastic grocery bag over the fill hole and then screw the cap on to keep the water out. Then some low life stole the tiller. They probably regret it.

I have acquired a notion that water droplets actually clog fuel filter or carburettor jets. That's why no cranking helps with it, and pouring it out from gas tank is needed.

Check for cracks on the rubber fuel hose from the gas tank clunker to the carb. These hoses rot over the years and when the cracks that develop get big enough and start sucking in air instead of fuel you'll never get that thing started.

Also, some machines have vented fuel caps. If the vents get plugged with grime you might need to clean the holes with a paper clip or high pressure air. As the fuel is sucked out of the tank it has to be displaced by an equal volume of air. If that cannot occur because the fuel tank is air tight then you're starving the engine of fuel.

There's many more reasons why the engine won't start. It could be a combination of things too. Tillers, for some reason, have the most finicky fuel systems I know of. Mantis is the most finicky brand.

Clean spark plug or new spark plug?

Pull the spark plug, gap it to about 20 t0 24 thousands of an inch, connect it to the coil wire and touch the thread to the block. Then pull the cord, if you get a strong spark check your compression. If you don’t get a good spark check your points and coil.

Check compression with a tester or put your thumb over the sparkplug hole and pull the cord, it should push air past your thumb no matter how hard you press your thumb over the hole. Do this a couple times and smell your thumb, it should smell of gas.

If you don’t smell gas on your thumb check your carb.

Make sure it is getting gas.

If it is getting gas make sure the needle valves are clean and adjusted right.

You need three things for a gas engine to run.


Clean fuel, clean fuel filter, and a clean carb.


Clean air filter, working baffles in carb, working cylinder valves, and compression (working piston and rings)


Timing (check key on flywheel), working coil, working points and gaped (Most are gaped 20 to 24 thou), a clean and working sparkplug gaped to 20 to 24 thou.

Check to see if the choke is open or closed. Is it in gear? If so make sure it's in neutral before trying to start it.