Coleman Powermate 3000-Will not start.
You may know this already but I'll go over how to troubleshoot a small gasoline engine :-)
To run properly these engines need 3 things a) the right fuel/air mixture into the cylinder, b) compression, and c) spark at the right time. As you check out the engine you prove to yourself that each of these things is there.
First, double check the fuel valve and the run/stop switch. I've forgotten this once or twice and wasted time fixing what wasn't broken.
Next pull the starter rope. Do you feel a fair amount of resistance that gets stronger then weaker as the engine turns over? This is also when I listen for any odd noises.
Double check the fuel level in the tank and the amount of oil in the crankcase. Again, we're systematically proving that the darn thing ought to work.
OK, got fuel in the tank, oil in the crankcase, all controls to "go", and it feels like we have compression - that leaves checking it for spark. Take out the spark plug and look at the end of it. If it isn't nice and clean go get a new one. Lay the spark plug against the cylinder head so that you can see the gap at the business end and gently pull the starter rope, you should see a nice bluish spark jump across the gap. You may need a friend to help by pulling the rope while you watch the gap ;-)
This doesn't check that the plug will spark when it's under compression in the cylinder but it proves that the electrical parts of the engine are working.
If there was any sort of spark at all reinstall the plug (use the new one if you found it dirty). Take the air cleaner off of the engine an inspect it, if it's dusty tap it against your hand to knock the dust out of it, if it's oily and/or wet get a new one. Get yourself a can of carb cleaner, brake cleaner, or other handy starting aid and shoot a 1 second blast of it thru the carb intake. You want to get the brake/carb cleaner past the carb and into the intake manifold. Do Not use ether or gasoline for this at penalty of your eyebrows. Close the choke half way and pull the rope, if the engine starts or tries to start and then stops you probably have carb problems, if there is no detonation at all from the cylinder you may have compression or spark problems.
Put a catch pan under the carb, I use a cut down 1 gallon oil container. Using a 13mm wrench loosen the bolt on the bottom of the carb bowl and then remove it by hand. You should see fuel start to come out of the hole where the main jet you just took off was. If you don't see fuel come out gently remove the bowl from the carb, be careful of the oring/gasket between the bowl and the carb body. At this point fuel should be pouring out into the catch basin, if it isn't you have to find out what's blocking the fuel supply. Shut off the fuel valve, many fuel valves have a built in filter in the body of the valve. If you've got one of these you can take the bottom of the valve apart with a 10mm wrench and clean/inspect the screen inside, be carefull of the oring here too.. If the filter is OK, remove the float and needle vale from the carb by pulling out the hinge pin in the float, when you turn the fuel valve back on fuel should pour out into the catch pan, if not you need to remove, check, and possibly replace the fuel line.
If you've got fuel to the carb (fuel poured into the catch pan above), you need to remove, clean, service (lube, inspect) and reinstall the carb. There aren't many adjustments on modern small engine carbs.
Get a spark tester and check that the engine gets spark with the plug installed. If it does not, you have to determine why starting at the run/stop switch. Find the (usually black) wire at the center of the switch and disconnect it. Check for spark again, if you got spark you may have a bad switch. If you didn't get spark you probably have a bad ignition module which is located under the blower housing and above the flywheel.
The only good way to check compression is to use a compression tester. You should see 50 psi or more of compression for the engine to work. If you don't have good compression, especially if you get very low compression check the valves first then the head gasket.
If everything checks, you have fuel, compression, and spark but the engine still won't run. You may have a broken flywheel key. To check that you have to remove the blower housing, the ignition module, and then the flywheel.
Hope this helps narrow down the problem, feel free to ask me directly if you need more help.
Dec 06, 2008 |
Coleman Electrical Supplies