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Troubleshooting Briggs and Stratton oil leak problems

The Briggs and Stratton lawn mower may have issues that present themselves as less severe.

For example, a common issue is whereby the engine fails to start or runs poorly. The problem could be untreated gas, low oil level, or a dirty carburetor.

But your Briggs and Stratton riding lawn mower leaking oil from the bottom could indicate a more significant issue.

However, that is not always the case because simple things such as overfilling the mower with oil can lead to some dripping off it.

On the other hand, a faulty part, like an air filter, could also be the primary cause of the leak. In this case, the air filter will be soaked in oil.

Essentially, when you notice a Briggs and Stratton V twin oil leak, the first thing to do is to identify the source or the cause.

That way, you will be better positioned to determine whether you can troubleshoot the issue or contact an expert to repair it.

Briggs and Stratton Lawn Mower

How to troubleshoot Briggs and Stratton oil leak problems

You can troubleshoot and stop a Briggs and Stratton engine from leaking oil by doing different things.

Here are a few worth considering.

1. Check the valve clearance

The Briggs and Stratton engine has a valve spring that keeps the valve closed. If the valve spring does not work well, the oil will leak into the combustion chamber.

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But if the valve spring works well, the next thing to check is the clearance. This is especially true if the Briggs and Stratton mower leaks oil from the valve cover.

A valve spring that sticks or leaks can stop the engine from running. Therefore, consider adjusting the valve clearance to the recommended settings.

2. Check the compression system

Air-fuel compression helps power Briggs and Stratton lawnmowers and other outdoor equipment. It has cylinders, rings, pistons, and valves. These components control how fuel vapors and air movement throughout the engine.

The work of the valves is to allow air in and out. On the other hand, the pistons move back and form to push the air-fuel mixture to the ignition system, while the rings ensure the entire system is tight and sealed.

Therefore, check the compression system to ensure everything works well to prevent oil leakages and the engine from starting.

You can begin by performing a compression system using a leak-down tester. The tester will detect engine faults like piston rings, cylinder head cracks, worn valves, and blown head gaskets, which contribute to oil leaks.

3. Check the gasket

A faulty gasket could be the cause of the oil leak. Generally, the Briggs and Stratton engine has an oil pan gasket that creates a seal between the oil pan and engine block.

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However, if you notice your engine overheating, you have a leaking oil pan gasket. That is because the gasket constantly heats up and cools down.

That action can cause it to wear and tear over time, thus causing the oil leak. Also, you may have a carburetor issue. If the carburetor is faulty, consider replacing it.

4. Check the oil level

Change lawn mower oil
Image: Tony

When you add oil to your Briggs and Stratton engine, avoid putting too much. Overfilling the oil reservoir will only cause the machine to leak from the reservoir cap.

Therefore, check the dipstick and add a bit of oil at a time.

5. Check the breather tube

The combustion chamber produces high temperatures when a Briggs and Stratton lawn mower operates.

As a result, the hot gases drive the engine to rotate the blades and power the engine. But the machine must find a way of relieving the air pressure. It does that using the breather tube.

The breather tube near the valves and behind a mower’s muffler does not allow the hot gases to move freely in the engine. Instead, it directs the air towards the exhaust system and muffler.

Furthermore, it collects oil to lubricate the piston. Therefore, if the breather tube is faulty, clogged, or cracked, it will cause an oil leak. The best solution is to replace it.

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You can troubleshoot Briggs and Stratton oil leak problems by identifying the cause. For example, start by checking the valve clearance and adjusting it to the recommended settings.

Also, check the compression system to ensure everything works well to prevent oil leakages.

Finally, if the oil leakage is because of a cracked breather tube or faulty carburetor, replace them with new ones.