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121252-0122-B8 Briggs and Stratton Engine - Overview
Diagrams for 121252-0122-B8
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$33.95
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Puller-flywheel
Part #19203
This flywheel puller is designed for servicing larger small engines by safely removing tightly seated flywheels without stressing the crankshaft or damaging ignition components. Constructed from heavy-duty steel and engineered to apply even pulling force, it makes accessing the magneto, crankshaft key, or ignition system straightforward d...Read moreuring repairs or overhauls. Built to OEM specifications for durability and precise fit, it’s a reliable tool for maintaining lawn mowers, generators, and pressure washers with compatible engines.
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$16.95
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Valve-Choke
Part #692567
$11.95
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Filter-a/c Foam
Part #493537S
Genuine Manufacturer Sourced replacement part used on a variety of Briggs and Stratton Engines. This filter adds a second layer of protection against airborne-dirt particle ingestion. This is a Foam Pre-Cleaner which is Sold Individually. Please note a Paper Filter and a Cover are both Sold Separately.
$7.95
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Cap-oil Fill
Part #281658S
This manufacturer approved replacement part is specially produced for use with Briggs and Stratton engines commonly installed on Toro lawn and garden equipment. It is utilized to keep the oil in the tank. Please note this durable plastic oil fill cap is sold individually.
$27.95
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Deflector-muffler
Part #395700
$11.95
In Stock
Kit-needle/seat
Part #398188
Genuine manufacturer approved carburetor needle valve for lawn and garden equipment engines. This item includes the seat. The needle valve opens and closes to control the flow of fuel into the carburetor. Make sure to disconnect the spark plug wire and drain all gasoline from the carburetor and fuel tank before starting a repair.
$6.95
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Washer-sealing
Part #271716
This authentic OEM sealing washer is designed for your lawn equipment to create a tight seal within the carburetor body, preventing fuel or air leaks. If you notice any signs of leaks, such as dripping fuel or hissing sounds, it may indicate a faulty or worn-out sealing washer. Additionally, you might be experiencing engine performance is...Read moresues like rough idling or difficulty starting. To replace the sealing washer, ensure that the machine is off and that the engine has cooled down. Remove the air breather cover and the filter itself, following the instructions provided in your user manual to access the carburetor. Depending on your specific equipment model, you may need to detach the springs from the carburetor choke mechanism, disconnect the fuel line and fuel tank, remove the choke lever, and detach the air breather base. Once you have located the carburetor, carefully unthread the main jet from the bottom of the carburetor bowl. Finally, slide off the old sealing washer, ensuring you take note of its positioning for accurate replacement. Please note that this sealing washer is sold individually.
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$8.95
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Filter-a/c Foam
Part #273356S
This is an OEM sourced replacement part used on Briggs and Stratton and Toro equipment. Its purpose is to provide an extra layer of protection from dust and other contaminants. One foam air cleaner filter is included per order. Please note, the main pleated paper filter is sold separately. Depending on your equipment you may need a scre...Read morewdriver to replace this filter. • Remove the cover • Take out the old filter • Secure the new filter in place • Reattach the filter cover
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$5.95
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Starter Pawl-Ratchet
Part #281505S
This Genuine OEM ratchet pawl is a critical component designed to engage the recoil starting system with the engine, ensuring smooth and reliable starts. Manufactured from durable plastic, this replacement part is engineered to match the original specifications for a precise fit and dependable performance. Over time, a worn pawl can cause...Read more the recoil mechanism to slip, making it difficult to start the engine. Replacing it restores proper function and helps extend the life of your equipment. Sold individually, this part is ideal for routine maintenance or repair of compatible outdoor power tools.
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$12.95
In Stock
Filter- A/C Cartridge
Part #491588S
This is a replacement air filter/AC cartridge for your small engine. The air filter prevents dirt and debris from entering the engine. Over time, the air filter can become clogged or damaged, and this can lead to reduced performance. This air filter is approximately 4 inches wide and approximately 5 inches long. To replace the air filter,...Read more locate the air filter cover on the side of the engine, unscrew it, and remove the old filter. Be sure to clear out any dirt, clippings, or other debris that has found its way into the air filter assembly before you insert the new filter. Reattach the air filter cover, and secure it with the screws. This product is sold individually.
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$5.95
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Engine Spark Plug Terminal
Part #493880S
This spark plug terminal is supplied directly from the original equipment manufacturer. The metal terminal is designed to fasten the spark plug to the engine lead wire. This component is sold individually, and needle nose pliers are helpful with the repair. Please refer to the appropriate diagrams of your engine model for the proper application of this hardware.
$33.95
In Stock
Pulley/spring Assembly
Part #498144
This manufacturer approved recoil starter pulley is designed for lawn and garden equipment engines. The recoil starter engages the drive cup on the flywheel to start the engine when pulled. This assembly includes: Plastic Pulley and a Metal Recoil Spring.
Common Symptoms of the 121252-0122-B8
How this model fails, and the parts that fix it.
Will Not Start
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Cannot pull starter cord out or engine will not turn over
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See how others fixed this model. Time, tools, difficulty, and steps that lead to victory!
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Search repair tips from other customers using simple keywords like "replace", "fit", "remove", "inspect". DIY doesn't mean you have to do it alone!
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Parts fit like a glove
2 of 3 people
found this instruction helpful.
Removed pull start assembly down to the crank. Installed motor housing, motor fan & rewind assembly. All went real good.
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Needed to replace muffler
1 of 2 people
found this instruction helpful.
Using a socket wrench with extension and a T20 star socket (you can use the appropriate hex head socket also) i removed to two bolts holding the muffler on. They are right on top of the engine and very accessible. Your model may have a heat shield that needs to be removed. Once the muffler is off remove the old gasket. It may be stuck to
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the muffler or exhaust opening on the engine. It should just pry of with a little effort. I did make sure there were no gasket pieces left behind. I placed the bolts through the flange of the new muffler and then slid the new gasket over the bolts. You can use a exhaust gasket sealant just hold it place while you place the flange in place and not have to worry about gasket dropping off. I just held it until I got the flange in place. I started the bolts by hand using the socket and extension. I alternated from each bolt until I had tighted it down. You can look up torque specs. I just used my grunt meter. It is good as new. Parts were OEM replacement. Not knock off almost right parts. I got very lucky when I found this company and will use them again.
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