Gas Snowblower: Engine runs rough

If your engine is running rough, a problem with the carburetor is a likely cause. Rebuild or replace the carburetor to fix a fuel delivery problem. A clogged fuel filter will also prevent the engine from getting fuel, causing the engine to sputter or run rough. Check the fuel filter and replace it if clogged. A dirty spark plug won't ignite the fuel consistently, causing the engine to miss and sputter. Check the spark plug and replace it if necessary. Incorrect valve lash could cause the engine to run rough so check and adjust the valve lash. Check the engine sump gasket because a leaking gasket can cause low compression and a rough running engine. A thorough snowblower tune-up can also help the engine run smoothly.

gas snowblower

These repairs may help solve your gas snowblower problem

Do a snowblower tune-up

Do a snowblower tune-up

A tune-up restores the snowblower to its peak operating condition. A tune-up includes changing the oil, cleaning the engine, replacing the air filter, checking the ignition system, inspecting the carburetor, testing the battery, adjusting the throttle and choke controls, and adjusting and lubricating all moving parts.

December 1, 2015
By Lyle Weischwill
How to replace a snowblower spark plug

If your snowblower won't start, the spark plug could be fouled or damaged. This DIY repair guide shows how to set the gap and replace the snowblower spark plug in 3 quick steps.

Repair difficulty
Time required
 15 minutes or less
Read more
Clean and  rebuild the snowblower carburetor

Clean and rebuild the snowblower carburetor

Rebuild kits are available for most carburetors. The kit contains the essential components such as jets, pins, seals and gaskets to overhaul the carburetor. You can sometimes fix a fuel supply problem by disassembling and cleaning a carburetor. Use the rebuild kit to rebuild the carburetor after cleaning it.

December 1, 2015
By Lyle Weischwill
How to rebuild a snowblower carburetor

The snowblower carburetor mixes air and fuel going to the engine. You might need to rebuild the carburetor if the snowblower won't start or dies soon after starting.

Repair difficulty
Time required
 45 minutes or less
Read more
Adjust the snowblower valve lash

Adjust the snowblower valve lash

The snowblower valve lash is the amount of clearance between the top of the valve stem and the rocker arm. Incorrect valve lash prevents the snowblower valve from opening or closing properly. valve lash is incorrect, the snowblower engine is hard to start, runs poorly and loses power. Premature valve failure also results from improper valve lash. Check valve lash after the first 25 hours of use and then every 100 hours. Adjust the valve lash if the snowblower engine won't start or runs poorly.

December 1, 2015
By Lyle Weischwill
How to adjust a snowblower valve lash

When a snowblower's engine loses power or is hard to start, it could mean the valve lash needs adjusting. This snowblower repair guide and video show how to adjust the valve lash in 30 minutes.

Repair difficulty
Time required
 30 minutes or less
Read more
Replace the snowblower fuel filter

Replace the snowblower fuel filter

The snowblower fuel filter screens particles from the gasoline as fuel moves from the fuel tank to the carburetor. Fuel won't flow if the snowblower fuel filter clogs. Replace the fuel filter if it's clogged or damaged.

December 1, 2015
By Lyle Weischwill
How to replace a snowblower fuel filter

When a snowblower won't start, it could be a clogged fuel filter isn't letting gas into the carburetor. This DIY repair guide and video explain how to replace a snowblower fuel filter in less than 30 minutes.

Repair difficulty
Time required
 30 minutes or less
Read more
Replace the snowblower spark plug

Replace the snowblower spark plug

The snowblower spark plug creates the spark that ignites the fuel, creating a controlled explosion in the cylinder to move the piston that drives the engine. The spark plug won't create spark if deposits build up on the spark plug electrode or if the ceramic insulation cracks. Replace the snowblower spark plug if it's fouled or damaged.

December 1, 2015
By Lyle Weischwill
How to replace a snowblower spark plug

If your snowblower won't start, the spark plug could be fouled or damaged. This DIY repair guide shows how to set the gap and replace the snowblower spark plug in 3 quick steps.

Repair difficulty
Time required
 15 minutes or less
Read more
Replace the snowblower carburetor

Replace the snowblower carburetor

Over time, varnish from stale gasoline builds up in the carburetor, decreasing the amount of air/fuel mixture reaching the engine. Replace the carburetor if it's severely clogged with varnish or if the orifices are clogged with debris and can't be cleared using carburetor cleaner and compressed air.

Replace the snowblower engine sump gasket

Replace the snowblower engine sump gasket

The sump at the bottom of the engine houses the oil pump and collects engine lubricant. A leak in the sump gasket decreases engine compression, making it difficult to start the engine. If physical examination of the sump gasket reveals a leak, replaced the gasket.

Symptoms for gas snowblowers

Choose a symptom to see related snowblower repairs.

Main causes: stale gas, clogged carburetor, clogged or broken fuel line, dirty spark plug, bad rewind starter, incorrect valve lash
Main causes: broken shear pins, worn or loose auger drive belt, auger drive cable failure, damaged auger, bad gear case
Main causes: loose drive clutch cable, damaged drive clutch cable, worn friction disc, scraper blade scraping the ground, engine problems
Main causes: punctured tire, damaged rim
Main causes: snow build-up in chute, chute drive mechanism failure, bad chute control assembly
Main causes: clogged chute, damaged auger blades, broken shear pins, worn auger belt, damaged gear case, engine problems
Main causes: dirty carburetor, stale fuel
Main causes: clogged chute, snow build-up in auger housing, broken auger shear pins, auger drive belt needs adjustment, auger cable problems
Things to do: replace the spark plug, change the oil, rebuild the carburetor, adjust valve lash, adjust or replace the belts
Repair guides for gas snowblowers

These step-by-step repair guides will help you safely fix what’s broken on your snowblower.

December 1, 2015
By Lyle Weischwill
How to replace a snowblower spark plug

You need a spark to fire up the engine of your snowblower, and that spark comes from a spark plug. You can replace one in minutes.

Repair difficulty
Time required
 15 minutes or less
December 1, 2015
By Lyle Weischwill
How to replace a snowblower stop switch

Replace the stop switch on your snowblower if your engine won't start.

Repair difficulty
Time required
 30 minutes or less
December 1, 2015
By Lyle Weischwill
How to replace a snowblower skid shoe

To prevent damage to your snowblower auger, replace the skid shoes when both sides of the shoe are worn. It's an easy repair that you can handle yourself.

Repair difficulty
Time required
 15 minutes or less
Articles and videos for gas snowblowers

Use the advice and tips in these articles and videos to get the most out of your snowblower.

November 1, 2014
How to lubricate a snowblower auger shaft video
By Sears PartsDirect staff

This video shows how to how and where to lubricate the auger shaft on a snowblower.

November 1, 2014
How to adjust a snowblower shift cable video
By Sears PartsDirect staff

This video shows how to adjust a snowblower's shift cable.

November 1, 2014
How to adjust snowblower skid shoes video
By Sears PartsDirect staff

See how to periodically adjust the skid shoes on a snowblower so they are flush with the ground.