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Lawnmower Won’t Start? Do this.

deposits and varnish in carburetor bowl

Lawnmower Won’t Start? Do this.

A lawnmower that won’t start, especially when taken from storage, is almost always due to one problem: bad gas.

Storing a lawnmower in the fall without adding gasoline stabilizer to the fuel tank can cause the fuel to break down and plug the fuel passages. If fixing that problem doesn’t help, there are a few other common maintenance practices to try, as we explain below.

Here’s what to do when your lawnmower won’t start

Replace the gas

Over time (like the six months your lawnmower sat in your garage over the winter), the lighter hydrocarbons in gas can evaporate. This process creates gums and varnish that dirty the carburetor, plug fuel passages and prevent gas from flowing into the combustion chamber.

The carburetor bowl below formed corrosion and deposits during storage, which can easily plug fuel passages and prevent the engine from starting.

Deposits and residue in carburetor bowl

Deposits and residue in carburetor bowl

Ethanol-containing gas can absorb water from the atmosphere, which can lead to phase separation, which occurs when ethanol and gas separate, much like oil and water. Ethanol that has absorbed enough moisture and has sat long enough can foul the fuel system and prevent the engine from starting.

No matter how many times you yank the starter cord and pollute the air with your advanced vocabulary, the lawnmower won’t start if it isn’t getting gas.

In extreme cases, evaporation of lighter hydrocarbons can change the gasoline’s composition enough to prevent it from igniting. The gas may be fueling the engine, but it doesn’t matter if it won’t ignite.

If you neglected to add gasoline stabilizer to the fuel prior to storage, empty the tank and replace with fresh gas. If the tank is nearly empty, simply topping off with fresh gas is often enough to get it started.

On some mowers, you can easily remove and empty the fuel tank. Sometimes that’s more trouble than it’s worth. In these cases, use a fluid extraction pump or even a turkey baster. (We keep them in the Sioux Falls location also)

Clean the carburetor

You’ve replaced the fuel, but your lawnmower still won’t start.

Next, try cleaning the carburetor. Remove the air filter and spray carburetor cleaner into the intake. Let it sit for several minutes to help loosen and dissolve varnish and gums.

On some carburetors, you can easily remove the float bowl. If equipped, first remove the small drain plug and drain the gas from the bowl. Remove the float bowl cover and spray the float and narrow fuel passages with carburetor cleaner.

This kind of “quick-and-dirty” carburetor cleaning is usually all it takes to get the gas flowing again and your lawnmower back to cutting grass.

If not, consider removing the carburetor from the engine, disassembling it and giving it a good cleaning. Be forewarned, however: taking apart a carburetor can lead to nothing but frustration for the uninitiated. Take pictures with your phone to aid in reassembly. Note the positions of any linkages or the settings of any mixture screws, if equipped.

If you’re at all reluctant, visit the servicing dealer instead. Also consider replacing the carburetor altogether. It’s a fairly simple process on most smaller mowers and it’s often less expensive than taking it to the dealer.

Clean/replace the air filter

With the air filter removed, now’s the perfect time to clean it. Tap rigid filters on a workbench or the palm of your hand to dislodge grass clippings, leaves and other debris. Direct compressed air from the inside of the filter out to avoid lodging debris deeper into the media.

Use soap and water to wash foam filters. If it’s been a few years, simply replace the filter; they’re inexpensive and mark the only line of defense against wear-causing debris entering your engine and wearing the cylinder and piston rings.

Check the spark plug

A dirty or bad spark plug may also be to blame. Remove the plug and inspect condition. A spark plug in a properly running four-stroke engine should last for years and never appear oily or burned. If so, replace it.

Use a spark-plug tester to check for spark. If you don’t have one, clip the spark-plug boot onto the plug, hold the plug against the metal cylinder head and slowly pull the starter cord. You should see a strong, blue spark. It helps to test the plug in a darkened garage. Replace the plug if you don’t see a spark or it appears weak.

While you’re at it, check the spark-plug gap and set it to the factory specifications noted in the lawnmower owner’s manual.

If you know the plug is good, but you still don’t have spark, the coil likely has failed and requires replacement.

Did you hit a rock or other obstacle?

We’ve all killed a lawnmower engine after hitting a rock or big tree root.

If your lawnmower won’t start in this scenario, you probably sheared the flywheel key. It’s a tiny piece of metal that aligns the flywheel correctly to set the proper engine timing. Hitting an immovable obstacle can immediately stop the mower blade (and crankshaft) while the flywheel keeps spinning, shearing the key.

In this case, the engine timing is off and the mower won’t start until you pull the flywheel and replace the key. It’s an easy enough job IF you have a set of gear pullers lying around the garage. If not, rent a set from a parts store (or buy one…there’s never a bad reason to buy a new tool) or visit the dealer.

My lawnmower starts, but runs poorly

If you finally get the lawnmower started, but it runs like a three-legged dog, try cleaning the carburetor with AMSOIL Power Foam. It’s a potent cleaning agent designed to remove performance-robbing carbon, varnish and other gunk from carburetors and engines.

Power Foam®

Buy AMSOIL Power Foam

Add gasoline stabilizer to avoid most of these problems

Which sounds better? Completing all these steps each year when your lawnmower won’t start? Or pouring a little gasoline stabilizer into your fuel tank?

Simply using a good gasoline stabilizer can help avoid most of the problems with a lawnmower that won’t start. AMSOIL Gasoline Stabilizer, for example, keeps fuel fresh up to 12 months. It helps prevent the lighter hydrocarbons from evaporating to reduce gum and varnish and keep the fuel flowing. It also contains corrosion inhibitors for additional protection.

Gasoline Stabilizer

Buy AMSOIL Gasoline Stabilizer

I have a five-gallon gas can in my garage from which I fuel two lawnmowers, two chainsaws, two snowblowers, a string trimmer, an ATV and the occasional brush fire. I treat the fuel with Gasoline Stabilizer every time I fill it so I never have to worry about the gas going bad and causing problems.

You can also use AMSOIL Quickshot. It’s designed primarily to clean carburetors and combustion chambers while addressing problems with ethanol. But it also provides short-term gasoline stabilization of up to six months.

The 8 Most Useful Skid Steer Attachments

The 8 Most Useful Skid Steer Attachments

The 8 Most Useful Skid Steer Attachments

As a young farm kid, before I could operate the tractors, I had to pick rocks and sticks in the fields. I sometimes unearthed boulders that would have broken the blades on the tiller immediately.

I remember thinking, “This can’t be the most efficient way to prepare a farm field – there has to be an easier way.”

One day, I went home and asked, “Don’t they make a Bobcat attachment for this?” My parents replied, “Well, yeah, but then what would you do? Sit at home inside and play video games?”

These days, I’m always looking for the best way to accomplish any task at hand. And, 20 years later, I’m still fascinated by what you can do with skid steer attachments. The process improvements are sensational.

Here is my list of the coolest skid steer attachments

Disclaimer: the following list is for the common person. The added value these attachments provide will differ depending on your line of work (construction, landscaping, farming, etc.).

1. Essential skid steer attachments

Bucket – I’m starting the list with the most affordable and practical attachment, which to me makes it the coolest. With a bucket attachment, I like to say I have access to the best wheelbarrow in the world. I have redone a handful of driveways with solely a skid steer and a bucket attachment. Everyone can use a skid steer bucket in their life. Well, not if you live in a skyscraper apartment.

Forks – These are most often used to move pallets of material or maybe 275-gallon totes of AMSOIL products. Forks are perfect for businesses that don’t quite need a forklift for everyday use. They’re practical for stacking lumber and building materials to be set in a garage.

Be sure to put blocks underneath so you can fit your forks underneath the next time you want to move something. Another reason forks are great? They’re affordable.

2. Brush Hog

Brush cutters are ideal for the initial pass when clearing land and mowing overgrown areas. As a kid (and adult), I used the brush hog to clear my ATV and dirt bike trails since the six-foot swath it cut was the perfect width.

Word to the wise: be careful with your speed and the size of brush. Thick brush can do harm to a brush cutter, requiring a lot of maintenance.

Shop AMSOIL skid steer and other power equipment lubricants

3. Tiller

While a tiller attachment isn’t a necessity, it can save you a ton of time and sweat equity. If you’re just tilling a little backyard garden, use a gas rototiller – it’s much more cost effective than renting a skid steer attachment. For large areas or when landscaping, you can’t beat a skid steer with a tiller attachment. Tillers are purpose-built for pulverizing the toughest soil, saving time and money.

4. Auger

Augers are used to drill holes for fencing, footings, trees and more. There are different drive systems for different types of soils. Augers can usually dig down about six feet, but you can buy extensions if need be.

Pro tip: using the hydraulics, give the auger a good shake after it’s pulled from the ground to avoid spraying dirt all over the place (and people) when you fire it up again.

5. Trencher

This one makes the list because of the time savings it offers. There are a variety of trencher options on the market. Before renting or buying, it’s important to know the depth and width of the trench you’re digging. Forty-two inch trencher attachments work well, especially for utility lines, irrigation systems and drain pipes. If you often need a trencher, there may be a better piece of equipment out there for you, like a narrow excavator bucket.

6. Landscape rake

Landscape rakes are used for cutting out soil and gathering sticks and rocks with ease. CAT’s landscape rakes pulverize, aerate and level the soil while collecting rocks and debris in a hopper. There are a few variations in landscaping rakes from the major manufacturers.

7. Sweeper

There are a few different kinds of sweepers available, including…

  • Pick-up brooms (utility brooms)
  • Sweeper brooms
  • Angle brooms

Utility brooms are a personal favorite. They collect dirt, rocks and other debris into a hopper to be dumped in a place of your choosing. Optional dust-control kits help prevent the amount of airborne dust nearby.

My only complaint? They’re a little too big for cleaning the garage.

Shop AMSOIL skid steer and other power equipment lubricants

8. Honorable mentions

The following honorable mentions didn’t quite make the main list due to the narrowness of the application or cost effectiveness. But they’re still worth considering for some people.

  • Bale spear – An absolute necessity on the farm. We used these for round bails the most. Stacking them on a trailer three high takes precision, which this affordable attachment easily provides.
  • Dozer blade – While practical for small soil movement and leveling, you can usually get by with a bucket.
  • Grapple buckets – Ever wish your hands were huge, powerful and felt no pain? You were probably wishing for a grapple bucket. This attachment is prefect for grabbing heavy, oddly shaped objects. They’re most often found in the demo, construction and trash-management industries.
  • Mulcher – Although mulcher attachments are a cool concept, they’re expensive. Mulchers are used on land that hasn’t been touched in a long time. They help reduce manual labor.

I can’t complain about picking rocks all summer in those fields; it shaped who I am. When I have kids, my rock-picking stories might be like my parents’ stories of “walking to school, in the freezing cold, uphill both ways.”

No matter the job for which you use your skid steer, make sure to maintain it properly so it lasts for years.

Updated. Originally published: July 25, 2017

AMSOIL vs. Mobil 1: How We Perform

AMSOIL vs. Mobil 1: How We Perform

AMSOIL & Mobil 1 – Compared

Most lists of top-10 performance mods include a turbocharger, supercharger, nitrous oxide or updated engine tune. Increasing the engine’s oxygen intake also increases fuel, which boosts power.

“If you love Mobil 1 you should  use Dollar General motor oil. It’s real good too” lol…

While all that extra power is great, it puts additional demands on your engine oil.

(See our 5 Ways to Boost Horsepower for Under $500.)

Horsepower riding on a sheet of paper

Your main bearings – and, for that matter, the time, money and effort invested in your vehicle – rely on an oil film that’s thinner than a sheet of paper. Adding horsepower increases rpm and engine stress, placing even more stress on the oil. Many enthusiasts make compensatory upgrades to the crank, pistons, cam, etc. to handle the additional pressure.

The shear importance of oil 

In this scenario, upgrading the motor oil is often overlooked. But it’s an important consideration since engine upgrades can increase shearing forces, which result in viscosity loss. And viscosity is the most important property of oil.

Check out this post for details: What Does Viscosity Mean (and How Does it Affect Your Engine)?

Shear results when one layer of fluid moves in a direction different from another layer of the same fluid.

Shear (often called mechanical shear) occurs when one layer of oil moves in the opposite direction of another layer of the same oil. A great example occurs between the piston and cylinder wall. These two oil films move in opposite directions under intense heat and pressure. This is why high-horsepower, high-rpm engines create increased possibility for viscosity loss due to shear.

This scenario can shear, or tear apart, the molecules of viscosity-improver additives, which are used to extend the viscosity range of the base oil. The application and type of base oil determine the type of viscosity improver. Some viscosity improvers resist shear better than others. And some synthetic oils don’t need viscosity improvers at all due to their ability to withstand shear.

A breakdown in protection

If the oil loses viscosity due to shear, it can fail to provide the required level of wear protection. Think of the force transferred through the piston, rod and crank to the thin oil film protecting the bearing. There’s not much room for error.

AMSOIL uses naturally shear-resistant base oils combined with top-tier, shear-stable viscosity improvers. AMSOIL synthetic motor oil withstands extreme heat and shearing forces, exceeding industry standards and outperforming competing brands. In fact, it fights viscosity breakdown 46 percent* better than Mobil 1. It stands up to the devastating effects of high-horsepower, modern engines for maximum protection.

 

FIND AMSOIL FOR MY VEHICLE

*Based upon independent testing of Mobil 1 Annual Protection Full Synthetic and AMSOIL Signature Series 5W-30 in the Kurt Orbahn test, oils purchased on 05/03/18.

Weed Eater Won’t Start? Try This

two cycle starting help

We’ve all been there – Weed Eater Starting Foes!

No matter what you call it – weed eater, weed whacker, string trimmer – chances are at some point it won’t start. Few things are more annoying than destroying your shoulder trying to start the weed eater when there’s work to do.

Fortunately, gasoline weed-eater engines are pretty simple, so most DIYers with a few tools and some basic know-how can get a stubborn trimmer running.

Here are our guidelines for troubleshooting a weed eater that won’t start

1) Check the gasoline

Gasoline can break down in as little as 30 days, especially today’s ethanol-containing gas. Homeowners sometimes stash their string trimmer in the garage at season’s end without stabilizing the gas. Oxygen has all winter to break down and ruin the gasoline, leaving you with a trimmer that won’t start in the spring.

If your trimmer falls into this category, empty the old gas from the fuel tank and replace it with fresh fuel.

2) Clean the carburetor

Once gas breaks down, varnish, gums and other debris can form inside the carburetor and clog the tiny fuel passages. This prevents fuel from reaching the combustion chamber and igniting.

Remove the air filter and spray carburetor cleaner into the intake. Let it sit for several minutes to help loosen and dissolve varnish. Replace the filter and try starting the trimmer.

If this doesn’t solve the problem, consider disassembling the carburetor to give it a more thorough cleaning.

Beware, however – taking apart a carburetor marks a point-of-no-return, of sorts. Understanding how the delicate gaskets, tiny screws and needle valves go back together can be a challenge, even on a relatively simple string-trimmer carburetor. Take pictures with your phone throughout the process to help reassembly. Clean all the openings and passages with carburetor cleaner.

If you’re reluctant to take apart the carb, visit the servicing dealer.

3) Clean or replace the spark plug

Oil deposits and carbon can foul the spark plug in a two-stroke engine if a low-quality oil is used. Deposits on the electrode prevent the plug from firing properly, which can reduce performance or prevent the engine from running altogether.

Plugs are inexpensive, so replace it if it’s fouled. If you don’t have a new plug available, clean the deposits from the electrode with light-duty sandpaper and check the gap. Consult the owner’s manual for the correct gap size.

If you know the spark plug is good, but the engine still doesn’t produce spark, the coil is likely to blame and requires replacement.

4) Clean or replace the air filter

A clogged air filter prevents the engine from receiving sufficient air to operate properly.

Before removing the air filter, brush away loose debris from around the filter cover and filter element. Tap rigid filters on a tabletop or the palm of your hand to dislodge any dirt or debris. Compressed air also works well. Make sure you direct air through the filter from the inside to avoid lodging debris deeper in the filter.

Avoid washing paper filters as this can collapse their micro-fine structure. Foam filters, however, can easily be washed using mild detergent and warm water.

As with the spark plug, however, replacement is often the best practice, especially if the filter is excessively dirty.

5) Clean the spark-arrestor screen

On many trimmers, a small screen covers the exhaust outlet and prevents sparks from exiting the muffler and potentially starting a fire.

As with plug fouling, too much oil in the gasoline, inferior oil and continued low-rpm operation can plug the screen with carbon deposits. This prevents exhaust-gas flow, which leads to power loss. In extreme cases, heavy deposits choke airflow enough to leave you with a weed eater that won’t start.

To fix the problem, remove the spark arrestor screen and spray it with a heavy-duty cleaner, like AMSOIL Power Foam®, to soften the deposits before cleaning the screen with an abrasive pad. Reinstall the screen and test the trimmer.

Replace the screen altogether if it’s excessively plugged with carbon.

6) Switch to a better two-stroke oil

Low-quality oil that leads to heavy carbon is often to blame for most of the problems on this list.

Using a good two-stroke oil that burns cleanly and helps prevent carbon deposits is one of the easiest maintenance practices you can perform to ensure your trimmer starts easily, runs well and last for years.

Buy SABER Professional

AMSOIL SABER Professional Synthetic 2-Stroke Oil withstands high heat to fight carbon in gasoline string trimmers and other two-stroke equipment. It’s tested and proven at any mix ratio up to 100:1, offering the convenience of one mix ratio for all your equipment. Plus, it’s formulated with gasoline stabilizer to help keep fuel fresh during short-term storage.

The images here show AMSOIL SABER Professional’s superior cleanliness properties. It’s just one reason professional landscapers, like Duluth Lawn Care, only trust AMSOIL products.

2-cycle mix ratios

AMSOIL SABER Professional mixed at 100:1 delivers better protection against power-robbing deposits than other oils mixed at 50:1.

View the complete test results here.

Follow the guidelines on this list to get your string trimmer back up and running…and to give your shoulder a break.

Help! How Many Quarts of Oil Does My Car Use?

Help! How Many Quarts of Oil Does My Car Use?

How Much Oil Does My Car Need?

The answer seems simple: probably about five quarts.

But, if you drive a small car with a four cylinder engine, it’s likely closer to four quarts. However, the V-8 engine in your truck could require about seven quarts. My in-laws’ RAM diesel pickup takes 12 quarts of motor oil.

You can see how the answer isn’t so simple after all.

To find out precisely how much motor oil your car needs, do one of the following:

  1. Check the owner’s manual

Dig the owner’s manual out of your glovebox and look up the information in the index. Eventually you’ll find it.

  1. Check the AMSOIL Product Guide

You can skip the hassle and use our Product Guide instead. Just input your vehicle information and, below the motor oil recommendations, you’ll find motor oil capacity (circled below in red).

What if the oil level is too low?

It could be due to a couple issues, including insufficient oil added during the last oil change or oil consumption. There are several reasons for oil consumption (in fact, you can read about 40 of them here). But here are a couple of the more common.

Leaking seals or gaskets – your engine uses seals in various places to ensure oil stays inside the engine while contaminants stay out. A prime example is around the crankshaft where it sticks out of the engine and connects to the transmission. Gaskets seal the uneven metal surfaces between parts to ensure, in part, that oil stays inside the engine. The cylinder head gasket is a notable example.

If the seals and gaskets become worn, brittle or deformed over time, they can result in oil leaks. The engine oil level will drop, depending on the severity of the leak. If your engine leaks oil, visit a mechanic and have it fixed.

Volatility – engine oil can evaporate when exposed to heat. The less stable the oil, the more readily it evaporates. As the engine is running, a thin film of oil coats the cylinder wall and piston skirt. Given its proximity to the fiery cauldron inside the combustion chamber, the oil in this area of the engine can easily volatilize, or evaporate. The by-products can exit the tailpipe as emissions. But they can also form harmful carbon deposits inside the engine that reduce efficiency and eventually lead to engine failure.

Synthetic motor oil is more resistant to volatility than conventional oil, so use a good synthetic to reduce oil consumption due to volatility and help keep your engine clean.

What if the oil level is too high?

It’s likely due to operator error; someone simply added too much last time the oil was changed or topped-off.

Too much oil is a bad thing. The spinning crankshaft and churning engine parts whip air into the oil, which can cause foam. The tiny bubbles travel between moving parts, where they rupture. When they do, nothing is left to protect metal surfaces from wear. Foam also increases heat, which causes the oil to chemically breakdown sooner.

If the crankcase is overfull, drain the excess oil until reaching the correct level.

Increased oil level can also be due to fuel dilution. This is when fuel enters the crankcase and contaminates the oil. In severe cases, enough fuel can enter the crankcase to noticeably increase the oil level. This is bad. Very bad. Fuel dilution leads to sludge, varnish and engine wear.

Check out this post for more on fuel dilution.

The presence of coolant in the oil can also increase oil level. Again, this is bad. Anytime something that shouldn’t be in your motor oil is present, wear protection suffers. Coolant in the oil is likely due to a bad head gasket, which is a costly repair.

One last word of advice: check your oil at least monthly to ensure the proper level. Make sure the vehicle is parked on a level surface to get an accurate reading. Finding out the oil is too low or too high before something goes wrong can save you a ton of grief in the long run.