Briggs & Stratton engines are not without problems, although, as with many brands, it is less an issue of design and manufacture. Poor maintenance is frequently the cause.
Any small engine is actually a masterpiece of engineering. It may look simple, but the design has been refined over many decades. However, as with all mechanical devices, things can go wrong. Regular maintenance is almost certainly the way to prevent potential problems.
If well maintained and not abused, a Briggs & Stratton engine may be expected to work effectively for up to 20 years, but nothing lasts forever, so if the motor is well and truly past its prime, with worn pistons, rings, or bearings, it may be time to replace the engine or at least undergo a major rebuild.
Such issues will be evident any time you use it, with resultant poor running, unpleasant noises, black smoke, and so forth.
Assuming the motor is not worn out, but merely just not running correctly, cleaning the air intake filter is usually the place to start, as is removal of grass and other debris that may foul the intake. Cleaning the fuel filter is another "must-do." This is a simple task that should take less than 5 minutes.
Cleaning the spark plug is another requirement - no engine will run for long with a loose or fouled spark plug.
The Three Main Problems
The problem of an engine running for only a few minutes before cutting out is not confined the Briggs & Stratton. It is a common fault in many small engines. There are only about three probable causes:
The first possible cause and the easiest to check is the spark plug, Remove and clean it. While it is out of the engine, hold it in a pair of insulated pliers, place it close to any solid part of the engine, and pull the starter cord.
A decent spark at the tip of the plug will indicate that the plug and plug lead are intact. If there is no spark, remove the plug from the lead and check for a spark at the end of the lead itself.
If there is no spark, the lead may have broken internally and should be replaced. It is unlikely to be the magneto that is faulty because if that were the case, the engine would not start at all.
Fuel in the tank is another source of potential problems. The fuel should be fresh - meaning not sitting in the tank for weeks or months at a time.
The actual fuel level may be the problem. Fuel level indicators are generally fairly reliable, but they can stick, resulting in a false reading, so it is prudent to check physically with a stick to see what the fuel level actually is.
A related problem may be an airlock in the tank or the delivery line to the carburetor. The cap has a small air vent that could be blocked, and rather than poke at it and cause worse problems, a good blast of compressed air will generally clear any blockage.
The fuel line should be inspected for wear or damage and may be introducing air into the delivery line. If in doubt, the line should be replaced with a new line of the same diameter, pushed all the way home, and clipped into place.
The carburetor is a frequent cause of problems, mainly due to a partly blocked jet (if a jet is fully blocked, the engine will probably not start at all).
Clearing jets is simple - carefully remove the carburetor from the engine, and place it on a towel or other surface that will not allow small components to roll off and be lost (don't laugh - this has happened to us all).
Remove the bowl from the bottom of the unit, then the needle. The needle is right at the center of the bowl and unscrews with a small flat-blade screwdriver.
Inspect the hole in the needle visually for blockage and gently blow out the hole with compressed air. While the needle is out, this is the time to blow out all of the gunk from the carburetor.
Reassemble the parts with great care—do not overtighten any screws and, in particular, ensure the gasket fits snugly when replacing the bowl.
The third potential problem could be the govenor—the rod and springs that control the engine speed relative to the load. If a spring has slipped or broken, the engine revs will not respond to whatever load is placed on the engine.
The choke position is important but if the choke will not open correctly, the engine is likely to cut out within a few seconds of starting.
Rebuild or Replace?
If all of the above has failed to correct the problem, an engine strip-down may be the only solution. This is not generally within the scope of the average owner, but there are several excellent Youtube videos to explain and illustrate the process.
It is, however, expensive to rebuild an engine, so a replacement may be a better proposition.
Depending on the engine that is selected as a replacement and whether it is a horizontal or vertical shaft model, the cost of that new engine can be as low as $A200 and up to about $A800.
The following is a list of all current Briggs & Stratton vertical shaft engines:
Lawn Mower Engines
- Model Series 9P700 - 5.50 Gross Torque/140cc
- Model Series 10T800 - 5.50 Gross Torque/158cc
- Model Series 126M00 - 6.75 Gross Torque/190cc
- Model Series 100600 - 7.00 Gross Torque/161cc
- Model Series 100800 - 7.00 Gross Torque/161cc
- Model Series 121Q00 Professional Series™ - 8.50 Gross Torque/190cc
- Model Series 121S00 Professional Series™ - 8.75 Gross Torque/190cc
Professional Series Riding Engines
- Model Series 31L700 Professional Series™ - 17.5 Gross HP/500cc
- Model Series 31Q700 Professional Series™ - 18.5 Gross HP/500cc
- Model Series 33M700 Professional Series™ - 21.0 Gross HP/540cc
- Model Series 44L700 Professional Series™ - 23.0 Gross HP/724cc
- Model Series 44Q700 Professional Series™ - 27.0 Gross HP/724cc
- Model Series 49M800 Professional Series™ - 30.0 Gross HP/810cc
Commercial Series Riding Engines
- Model Series 44Q900 Commercial Turf Series™ - 27.0 Gross HP/724cc
- Model Series 49M900 Commercial Turf Series™ - 30.0 Gross HP/810cc
Power Built Series
- Model Series 215800 Power Built™ - 10.5 Gross HP/344cc
- Model Series 31A600 Power Built™ - 15.5 Gross HP/500cc
- Model Series 31C700 Power Built™ - 17.5 Gross HP/500cc
- Model Series 31N700 Power Built™ - 18.5 Gross HP/500cc
Intek Series Engines
- Model Series 217900 INTEK™ - 11.5 Gross HP/344cc
- Model Series 219900 INTEK™ - 12.5 Gross HP/344cc
- Model Series 31G700 INTEK™ - 17.5 Gross HP/500cc
- Model Series 331800 INTEK™ - 21.0 Gross HP/540cc
- Model Series 445500 INTEK™ - 23.0 Gross HP/724cc
- Model Series 305700 Vanguard™ - 16.0 Gross HP/479cc
- Model Series 356700 Vanguard™ - 18.0 Gross HP/570cc
- Model Series 358700 Vanguard™ - 20.0 Gross HP/570cc
- Model Series 386700 Vanguard™ - 23.0 Gross HP/627cc
And the following is a list of horizontal shaft engines:
- Model Series 83100 - 5.50 Gross Torque/127cc
- Model Series 12T100 - 8.00 Gross Torque/205cc
- Model Series 12S400 - 9.00 Gross Torque/205cc
- Model Series 15T200 - 11.50 Gross Torque/250cc
- Model Series 20T200 - 14.50 Gross Torque/305cc
- Model Series 20S200 - 14.50 Gross Torque/305cc
- Model Series 21S200 - 16.50 Gross Torque/342cc
- Model Series 25T200 - 21.00 Gross Torque/420cc
Snow Series Engines
- Model Series 12D100 Snow - 9.00 Gross Torque/205cc
- Model Series 15C100 Snow Professional - 11.50 Gross Torque/250cc
- Model Series 20M300 Snow Professional - 14.50 Gross Torque/305cc
- Model Series 21M300 Snow Professional - 16.50 Gross Torque/342cc
- Model Series 25M100 Snow Professional - 21.00 Gross Torque/342cc
- Model Series 50000 Vanguard™ - 2.4 Gross HP/81cc
- Model Series 86400 Vanguard™ - 4.0 Gross HP/127cc
- Model Series 118400 Vanguard™ - 6.0 Gross HP/182cc
- Model Series 13L300 Vanguard™ - 6.5 Gross HP/205cc
- Model Series 138400 Vanguard™ - 7.5 Gross HP/216cc
- Model Series 185400 Vanguard™ - 9.0 Gross HP/297cc
- Model Series 19L200 Vanguard™ - 10.0 Gross HP/305cc
- Model Series 235400 Vanguard™ - 11.0 Gross HP/392cc
- Model Series 245400 Vanguard™ - 13.0 Gross HP/392cc
- Model Series 305400 Vanguard™ - 16.0 Gross HP/479cc
- Model Series 356400 Vanguard™ - 18.0 Gross HP/570cc
- Model Series 385400 Vanguard™ - 21.0 Gross HP/627cc
- Model Series 386400 Vanguard™ - 23.0 Gross HP/627cc
- Model Series 543400 Vanguard™ - 31.0 Gross HP/896cc
- Model Series 613400 Vanguard™ - 35.0 Gross HP/993cc
If replacing a Briggs & Stratton manufactured engine, you need the stamped Engine Model, Type, and Code numbers.
If not a Briggs & Stratton manufactured engine, you need the engine brand, power rating, and model number. (ex. Tecumseh 10 HP Model HMSK 22-22222d).
Equipment information, including brand name, type, and model numbers (ex. John Deere Model 316 lawn tractor).
If you need to modify the engine’s existing electrical system to match a replacement engine, an electrical schematic is available on the Briggs & Straton website, which is s also an excellent source of information for specifications and other exchange details.
In conclusion, proper maintenance is the key to longevity, but if all else fails, this is one brand where replacement parts and/or complete engines are readily available.
Briggs & Stratton History
The original firm Briggs & Stratton was founded in 1908 as a collaboration between Stephen Foster Briggs and Harold Stratton. Their business model was based on the expectation of significant growth in the automobile industry.
In 1919 the company purchased the manufacturing rights for a small petrol-engined car manufactured by A.O. Smith where the motor was mounted on a 5th “motor wheel.”
The “Flyer” vehicle was considered to be the cheapest of all automobiles. The engine was redesigned to increase the power output.
In 1925, Briggs & Stratton sold the rights to the Flyer but continued to manufacture the engines that were subsequently incorporated into many of the company’s later products, including lawnmowers, washing machines, and many others.
For WW2 production, the company successfully designed and produced aluminum engine blocks with cast-iron liners and this led to continued output expansion during the 1950s and 1960s.
In 1995, the automotive component business was sold, and the company concentrated on other products.
In 2000, the company bought a generator business and renamed the company Briggs & Stratton Power Products. A major customer later went into liquidation, so Briggs & Stratton purchased the name, marketing rights, and product designs of that business.
There have been many other acquisitions and joint ventures like Diahatsu and Toyota in the company’s history, but many were unsuccessful. Briggs & Stratton finally sold the company to a private investor to avoid further liabilities, and the brand continued under the new ownership.
In July 2020, Briggs & Stratton filed for Chapter 11 bankruptcy and KPS Capital Partners purchased a majority of the company, eliminating the $900 million owed to creditors. The causes of failure have mainly been attributed to poor management and especially a disregard for any form of worker unionism.
Despite its various disasters and under current ownership, Briggs & Stratton is now the world’s largest producer of small engines not only for its own branded products, but also as the power source for many other brands of generators, lawnmowers, and related items.
Of the various models, the Briggs & Stratton iS SERIES engines represent the best performance package, delivering good power. They are also claimed to be the easiest starting lawn mower on the market.
That said, arguably, the brand is not as well regarded as Honda, or Robin (Suburu) but both of the latter sell at a higher price, mainly due to superior design, greater power output, and reliability.