Briggs and Stratton Ignition Coil Problems

An ignition coil is a small yet vital part of your Briggs and Stratton engine, it’s responsible for transferring voltage from the battery to the spark plug to ignite your machine into action. But what happens when there are Briggs and Stratton Ignition Coil Problems? 

Suddenly, that modest lawn mowing task turns into a Herculean challenge replete with frustration and confusion. With surprisingly little information available on this topic, many people find themselves lost in a maze of wires and engine parts trying to diagnose their ignition coil problems.

So, we have come up to shed light on these issues, so you can feel confident about tackling Briggs and Stratton Ignition Coil Problems head-on, whether you’re an experienced mechanic or a novice just starting with DIY repairs.

Briggs and Stratton Ignition Coil Problems

Briggs and Stratton Ignition Coil Problems

Understanding your Briggs and Stratton ignition coil problems is paramount not just for solutions but also for preventing potential damage; thankfully these engines bear detailed symptoms when they flounder. 

From reluctant starts to misfires, there’s an opportunity for keen eyes to comprehend underlying ignition inconsistencies. Let’s have a look at what issues mostly bothered Briggs and Stratton owners. 

Failed to Start the Machine

Several Briggs and Stratton 6HP B&S engine lawn mower owners have complained that they failed to start the machine despite regular use and previous reliable performance. After checking the usual issues and finding, they noticed no spark on the ignition testing tool. 

In most cases, they remained hesitant if the coil could suddenly fail. Some of them have replaced coils on hard-starting engines before, but never experienced a coil failure between uses, raising doubts about the cause of the problem.

Usually, it’s not uncommon for a coil to malfunction even after functioning flawlessly. Despite its age, your equipment is modern enough to incorporate an integrated module-type coil. There’s a likelihood that the electronic trigger within the coil has malfunctioned, necessitating a replacement of the entire coil assembly.

However, if your machine is older than you perceive and still operates on point-type ignition, the points may be defective. I’m uncertain whether it was Briggs or Tecumseh that utilized a points push rod. Nevertheless, there’s a possibility that they’ve become stuck open due to a sticky push rod. 

Wear and tear might have rendered the push rod incapable of opening the points. Furthermore, if your machine employs a cam-type points actuator, it could be that the rubbing block on the points arm has completely worn out. As another response suggested, if your machine uses a point-type ignition system, there’s also a chance that the condenser has failed.

Finally, if your device does come with an integrated ignition module type coil and needs replacement – ensure you install it correctly. These modules won’t ignite if installed upside down because they’re sensitive to rotation direction. Nowadays, though, manufacturers often include direction arrows on coils for guidance.

No Spark

The B&S lawnmower with a 3 HP magneto and points engine stopped working and doesn’t produce a spark. The owner tried a new plug, checked the condenser and points, and disconnected the kill switch for testing, but found nothing wrong. The continuity test showed a possible short to ground from the condenser point, but it was determined to be the resistance of the primary coil. 

Assuming that the engine in question is indeed a Model 9, it’s crucial to understand that the Briggs Magnetron or any other electronic substitute for the points and condenser cannot be utilized. This is because this specific engine was designed to operate with the Briggs Magnematic magneto. The Magnematic mag is unique as it features an integrated mechanical ignition advance system within its camshaft. 

If you attempt to use a solid-state ignition with this mag, you’ll find yourself in a precarious situation where the ignition is too far advanced upon starting, causing the engine to abruptly yank the starter rope from your hand during startup. 

The inability to use the Magnetron system stems from the placement of the magneto magnets – they’re not located in the flywheel, but rather housed separately in a hub on the crankshaft beneath it.

Moreover, it’s important to note that there’s no key connecting the flywheel and crankshaft. The Mag Coil primary (the wire linked with points) has an extremely low resistance, approximately 1 to 2 OHM using the engine block as a common reference point. 

It’s highly unlikely for an ohmmeter to differentiate between this coil’s primary resistance and ZERO resistance of a closed set of points. Additionally, you should measure spark plug wire resistance relative to engine ground, which ideally should fall within the Kohm range.

Frequent Coil Failure

Frequent ignition coil failure in Briggs and Stratton lawn mowers has been troubling numerous owners. A stator comprises charging coils that are located beneath the flywheel, which is fitted with a sequence of magnets. As the flywheel rotates, these magnets sweep over the stator coils, resulting in the generation of electricity. 

This form of electricity is known as Alternating Current (AC), which is subsequently converted to Direct Current (DC) by either a diode situated in the wiring or by a voltage regulator. The DC electricity then travels via wires to the battery for charging purposes.

In instances where a battery persistently depletes, this implies that one or more components are malfunctioning. Occasionally, components can fail without any clear cause. 

However, most often system burnouts occur due to improper handling such as attempting to jump-start the mower with a car when the battery has drained out and there’s no time for proper charging. This action typically results in damaging the mower’s charging system because it isn’t designed to be compatible with that of a car or truck.

The initial components likely to fail under such circumstances are either the diode or voltage regulator. Sometimes you might be fortunate enough and only need to replace these parts. However, more often than not, you’ll also need to replace the stator.

It’s crucial when replacing your battery to ensure its quality, as cheap ones tend not to perform well in most situations.

How To Replace A Briggs & Stratton Ignition Coil

Replacing the ignition coil on a Briggs and Stratton engine takes some level of expertise, but with careful attention, you can accomplish this task.

Begin by safely disconnecting the spark plug wire. Then, locate the ignition coil mounted on the motor – generally, this is directly beside the flywheel. Carefully remove it by unscrewing all fastening bolts.

Now prepare to install your new ignition coil. Before securing it in place with screws, ensure that there’s an appropriate level of clearance between the magnetic coil and flywheel (0.010-inch gap for optimal performance). This spacing is critical to avoid any damage or poor running conditions. 

Finally, reconnect your spark plug wire. Be sure to securely attach everything so as not to cause unnecessary wear or misfiring in future use. Following these guidelines will ensure a successful replacement of the Briggs and Stratton ignition coil.

Final Words

Briggs and Stratton ignition coil problems are common, but typically straightforward to diagnose and resolve. Regular maintenance is key in preventing these issues, helping to ensure that your engine runs smoothly. Utilizing high-quality replacement parts when necessary can also prolong the lifespan of your equipment. 

Therefore, it’s worth investing time and effort into learning how to properly care for your Briggs and Stratton machinery. Remember, if you find any difficulties or persistent issues, do not hesitate to consult a professional mechanic or authorized service center for assistance.

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