Replacing Stihl Blower Fuel Tank Vent: Step-By-Step Guide

If you're experiencing issues with your Stihl leaf blower, such as inconsistent performance or difficulty reaching full throttle, the fuel tank vent may need to be replaced. The fuel tank vent is an important component that allows air to enter the tank and can affect the machine's performance if it becomes clogged or blocked. In this guide, we will walk you through the process of replacing the fuel tank vent on your Stihl blower, covering topics such as accessing the vent, identifying the correct replacement part, and ensuring proper installation. By following these steps, you can help ensure your blower operates at its full potential and avoid future performance issues.

How to identify a clogged fuel tank vent

A clogged fuel tank vent can cause a variety of issues with your Stihl blower, such as loss of power, difficulty starting, or the engine stopping unexpectedly. To identify a clogged fuel tank vent, you can perform the following steps:

• Listen for unusual sounds: Pay attention to any unusual sounds coming from the blower, such as a vacuum-like sound when you open the fuel cap. This could indicate that air is being sucked into the tank, suggesting a problem with the vent.
• Observe the blower's performance: If your Stihl blower starts and runs poorly for a few minutes before quitting, a clogged fuel tank vent could be the issue. This is especially true if loosening the gas cap seems to resolve the issue temporarily.
• Check the fuel cap: Ensure that the fuel cap is vented. If it is not vented or appears to be clogged, this could be the source of the problem.
• Inspect the vent: Locate the vent on your Stihl blower, which is typically a small plastic circle with holes found under the airbox cover. Carefully remove it with a screwdriver and inspect it for any debris or blockages.
• Perform a pressure test: Block all the holes in the fuel tank and apply slight pressure. If air blows out of the vent, it may be clogged or not functioning properly.
• Observe the fuel flow: If the blower struggles to draw fuel or you cannot hear anything when blowing down the fuel pipe towards the carburettor, the vent may be clogged.
• Compare with a new vent: If you have a new or known functioning vent, compare it with the one on your blower. If the old vent looks dirty, damaged, or significantly different, it is likely clogged and needs to be replaced.

If you suspect that your Stihl blower's fuel tank vent is clogged, it is recommended to replace it with a new one. Additionally, always refer to the official Stihl manuals and safety guidelines when performing any maintenance or repairs on your equipment.

How to remove the fuel tank vent

To remove the fuel tank vent on a Stihl blower, you will need to identify the location of the vent. It is usually a small, black, plastic circle with a bunch of holes, located under the airbox cover or on top of the tank, behind the gas cap.

Once you have located the vent, you can use a screwdriver to gently pry it out. It is recommended to spray a little penetrating lubricant around the edge and let it soak for a minute before attempting to remove the vent, as this will help loosen any built-up residue and make it easier to remove.

After removing the old vent, you can install a new one by simply snapping it into place. Ensure that you have the correct replacement part for your specific Stihl model.

It is important to note that the fuel tank vent plays a crucial role in the blower's performance. It is designed to allow air to enter the tank while also preventing fuel from leaking out. Therefore, it is essential to ensure that the vent is functioning properly and is not clogged or damaged.

How to clean the fuel tank vent

To clean the fuel tank vent of a Stihl leaf blower, you will need to locate the vent first. It sits on top of the tank, about 5/8" in diameter, black, to the left of and behind the gas cap when the gas cap side of the blower is facing you. It also has an O-ring (older version) or a grommet (newer version) as a separate service part.

Once you have located the vent, you can use a screwdriver to pry it out. Be careful not to use too much force, as the filter and/or the tank could be damaged in the process. After removing the vent, spray a little penetrating lubricant around the edge and let it soak for a minute. This should help loosen any built-up dirt or debris. Finally, use a clean cloth or brush to wipe away any remaining dirt or residue.

If your Stihl blower is experiencing issues such as loss of power or inconsistent performance, a clogged fuel tank vent may be the culprit. Cleaning or replacing the vent is a relatively straightforward process and can help improve the performance of your blower.

It is important to note that using compressed air from the filler cap to blow out any obstruction in the tank vent is not recommended, as the tank vent has a check valve that should not prevent any air from coming in.

How to replace the fuel tank vent

To replace the fuel tank vent on a Stihl leaf blower, follow these steps:

Firstly, it is important to identify the model of your Stihl blower, as there are different versions of the fuel tank vent, depending on the model. The vent can be identified as a black, circular component, about 5/8" in diameter, located on the top of the gas tank, to the left of and behind the gas cap when the blower is facing you.

If your model has an o-ring, the part number is 0000-350-5800. If your model has a grommet, the part number is 4203-350-5801. These numbers may have changed, as the information is a few years old. You can purchase these parts online.

Once you have the correct replacement part, you can remove the old vent by prying it out with a screwdriver. Spraying a little penetrating lubricant around the edge first will help to loosen it. Be careful not to damage the filter and/or the tank when prying out the old vent.

Then, simply snap the new vent into place, ensuring that it is secure.

It is also worth noting that the fuel tank vent should suck air in and not blow out. If you block all the holes and put pressure into the tank, air should not blow out of the vent.

How to test the fuel tank vent

To test the fuel tank vent on a Stihl blower, you can check for a few common issues. One way is to observe if the blower is losing power or stopping despite the trigger position or choke. If this is the case, you can try opening the fuel cap and replacing it to see if the blower starts working again. This is a quick test to see if the issue is related to the fuel tank vent.

Another way to test the fuel tank vent is to observe if there is a build-up of pressure in the gas tank. If you notice that the gas tanks build up significant pressure, you can try opening the caps to relieve the pressure and see if that helps with starting the blower. This issue could be related to a faulty vent or a problem with the fuel/oil mix.

Additionally, you can try cleaning the plugs and checking if that improves the blower's performance. If the vent is clogged, it may need to be replaced. The fuel tank vent for Stihl blowers is a common wear item and is located under the airbox cover. It is a small plastic circle with multiple holes in it.

To replace the fuel tank vent, you can pry it out with a screwdriver and spray a little penetrating lubricant around the edge to help remove it. You can then order a replacement vent online or from a Stihl dealer.

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