Small Engine Troubleshooting: Fix Your Lawn Mower, Chain Saw, or Leaf Blower

By Pat Stone
Published on May 1, 1989
article image
by Adobestock/auremar
With a little know-how, you can soon learn how to diagnose and fix common problems with your lawn mower's engine.

Ah, spring, time to get outside and do. Cut that grass! Turn that soil! So you roll the old lawn mower or rotary tiller out of storage, give the crank a couple of vigorous pulls–and a few more pulls–and a few more pulls–and then start cursing. “The !&@*!! thing won’t start!”

What now? If you’re already a shade-tree mechanic and know a few things about small engine troubleshooting, you hunker right down and start tinkering. But, if like me (a certified carburetor klutz) you’re frankly intimidated by that mishmash of wires, hoses, valves and levers, you probably just keep doing the only thing you know how to do: Yank the crank. A few dozen pulls later, your arm’s sore and your temper’s shot. Defeated, you roll the renegade yard-aid back into the shed and storm into the house. One perfect spring day–ruined.

Your options now? Either hope the machine’ll change its mind and crank up the next time you take it out, or haul the blamed thing off to a repair shop. You’d probably take it to a shop right away except for that nagging fear that the malady is some simple little thing that any nitwit should know how to fix–and that your mechanic will be only too glad to point this out.

If this scenario sounds familiar to you, read on. The purpose of this article is to help you learn how to diagnose common small engine problems, fix the ones you can and toss up your hands gracefully when you can’t. It’s based on the hands-on know-how of Dennis Burkholder, MOTHER’s own workshop wizard. In his 13 years with MOTHER, our “Mad Swede” has had to build everything from a supposedly perpetual motion machine (“a perpetual headache machine,” Dennis called it) to a leaning, three-wheeled automobile. Before coming to us he did such things as help design lawn mowers and even test-drive snowmobiles. The man knows engines inside and out.

Before we begin, I need to share a confession, define a few parameters and offer a bonus.

The confession: We can’t begin to cover all small-engine models and problems. We’ll just hit some common small engine problems that almost anybody can treat–by following a logical troubleshooting sequence through the engine. Maybe these steps will help you shake off any timidity and get you interested in exploring and learning more. (There are plenty of good books and mechanics to guide you.) But even if you go no further than the steps we’ve outlined, we’re betting you’ll be able to fix the great majority of start-up troubles that strike your small engines.

Comments (0) Join others in the discussion!
    Online Store Logo
    Need Help? Call 1-800-234-3368