"Won't Start"

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That ought to clean up your no-fuel problem. If not, you know where to go.

OK, 'fess up: Did you store your mower "wet"?

Wet Plug = Too Much Fuel

Got a wet plug? (Do little white puffs of smoke come out of the muffler, but the engine doesn't really run? Do you smell gas?) You're flooding the engine. Maybe you've just been cranking so much that you've pulled too much gas into the ignition chamber. You can remove the plug and crank some more (the engine won't suck fuel with the plug out), then try again with the plug back in. Or try the easy way: Take a break. Drink some iced tea and come back in 10 minutes when the excess fuel's had a chance to vaporize. (It will vaporize more quickly if the plug's been removed.)

Still no luck? Take off your air filter and crank some. Did it fire up? If so, you need to fix that dirty filter-it's blocking good air flow. Clean foam filters by washing them in kerosene, solvent or dishwater, rinsing them out, then giving them a light, squeezed-in coating of SAE 30 motor oil (Fig. 13). Replace paper filters.

That wasn't the problem? Try this. If you've got a Tecumseh engine, rig a coat hanger wire so you can pull the governor all or barrel (Fig. 15) so it holds the choke open the way back while you're cranking (Fig. 14). and lets in lots of air while you're cranking. If you're a Briggs owner, take the air filter That didn't work, either? OK, OK. jiggle off, and set that long screw in the carburet- your Tecumseh float valve just like you would if the plug wasn't getting enough gas. Maybe that'll fix things.

With a Briggs, it could be that your choke doesn't open up properly. Take the air cleaner off, unhook the spark plug, and set the engine throttle on a setting between start and normal running level. Pull the crank and see if the choke disk jiggles (to let more air in).

If it doesn't, replace the carburetor. You can often get a working carb with gas tank inexpensively at a local flea market.

Another Briggs trouble could be a needle valve that's too open, letting too much fuel through. Tighten it (clockwise) by quarter turns until the engine runs evenly.

Tips and a Tale

We've now run through Burkholder's list of easy carburetor fix-its. (Float valves can be adjusted, but that's not so easy.) There's one other common lawn mower ailment you can deal with at home. If despite all your efforts your mower doesn't run, or runs rough, or is hard to start when it's hot, you may have a sheared shaft key. This is usually caused when the blade bangs hard into some object. (Did that happen and the mower keep running, but the next time you tried to start 'er up, it wouldn't go? Ah hah!)

The key is a small, about one-half-inch-long metal piece (Fig. 9) that connects the main mower shaft and the flywheel. (Engines that use belts to connect the drive and the object being driven are not likely to have key troubles.) If the key's been banged hard, it may be sheared-actually, partly indented-throwing the flywheel slightly off its alignment on the shaft and thereby making the engine ran rough (if at all). To remedy this, take the flywheel off the engine exactly as described before. Now look down at the key. If it looks like one in Fig. 16, work your way down until you can get the key out. Replace it, and your machine is bound to run a lot better.

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