Replacing The Fuel Line Of Stihl Ms310: A Step-By-Step Guide

The Stihl MS310 is a chainsaw that requires regular fuel line replacement due to the quick ageing of its fuel lines as a result of fuel impurities. This process involves first draining the old fuel, then removing the fuel filter and air filter before disconnecting the fuel lines from the carburetor and engine. Next, new fuel tubing should be cut and tapered before being fed through the fuel tank and connected to the carburetor, with Stihl press fluid used to coat relevant parts. Finally, the new fuel filter and air filter should be reconnected before closing the fuel tank.

Tools required for the job

To replace the fuel line of a Stihl MS310 chainsaw, you will need the following tools:

• An approved fuel container to drain the old fuel from the tank
• A metal hook (baling wire) to remove the fuel filter at the bottom of the tank, and to pull the main fuel line up into the tank opening once you've replaced the fuel line
• A sharp cutting tool, such as a knife or scissors, to cut off two lengths of fuel tubing about 6 inches long, and to slice a 45-degree taper into one end of both lines
• Stihl press fluid to coat the new suction hose, the stub and end of the return hose, and the other end of the return hose and the suction hose

Draining the fuel tank

To drain the fuel tank of your Stihl MS310 chainsaw, you will need an approved fuel container and a metal hook (baling wire).

First, open the fuel tank cap. Drain all the old fuel into the approved fuel container. Pull the fuel filter at the bottom of the tank upwards, using the metal hook. Then, pull the fuel filter off the end of the suction hose.

Next, remove the air filter cover and unhook the air filter. Remove the two mounting screws holding the air filter box in place. Now, you can remove the choke cover plate on top of the carburetor and unhook the throttle cable from the choke cover plate.

At this point, you can move on to pulling the fuel lines out of the engine and replacing them with new ones. However, if you simply want to clean the fuel lines and put them back, skip the next steps and proceed to the final paragraph.

To remove the fuel lines, start by pulling the fuel return hose off the stub next to the spacer flange using your fingers. Then, pull the fuel suction hose out of its seat on the carburetor. Pull both lines out of the engine and throw them away.

Finally, push the main fuel line up into the tank opening using the metal hook. Push the nozzle of the new fuel filter firmly into the suction hose. Refit the gas cap, air filter box, air filter, and filter cover before reusing the Stihl.

Removing the fuel filter

To remove the fuel filter of a Stihl MS310 chainsaw, you will need an approved fuel container and a metal hook (baling wire).

First, open the fuel tank cap and drain all the old fuel back into the fuel container. Then, pull the fuel filter at the bottom of the tank upward using the metal hook. Finally, pull the fuel filter off the end of the suction hose.

To replace the fuel filter, push the new fuel filter's nozzle firmly into the suction hose.

Replacing the fuel lines

The fuel lines on every Stihl MS310 engine contain a main or suction hose and an impulse or return hose. These hoses suck gas from the tank into the carburetor, and any excess fuel returns to the tank to be reused. The lines age quickly due to fuel impurities and must be replaced almost every season. Clogged or dirty fuel lines are also the cause of many common engine problems.

To replace the fuel lines, first open the fuel tank cap and drain all old fuel back into an approved fuel container. Pull the fuel filter at the bottom of the tank upward using a metal hook, then remove it from the end of the suction hose. Next, remove the air filter cover and unhook the air filter. Take out the two mounting screws holding the air filter box in place. Now, remove the choke cover plate on top of the carburetor and unhook the throttle cable from the choke cover plate.

Pull the fuel return hose off the stub next to the spacer flange, then pull the fuel suction hose out of its seat on the carburetor. Pull both lines out of the engine and dispose of them. Cut off two 6-inch lengths of fuel tubing and slice a 45-degree taper into one end of each line. Unbend the hook in a metal wire and insert it into the suction hose. Push the hook and suction hose through the main fuel hole in the fuel tank, then withdraw the metal wire.

Coat the grommet on the new suction hose with Stihl press fluid. Push the fuel suction hose down until the rubber lip is properly seated and the flange on the hose lies flat against the fuel tank. Now, coat the stub and end of the return hose with Stihl press fluid. Push the return hose until it stops against the stub.

Coat the other end of the return hose and the suction hose with Stihl press fluid. Connect the suction hose to the intake valve on the carburetor, then connect the return hose to the outtake valve. Make sure both hoses are properly secured against their respective valves.

Pull the main fuel line up into the tank opening using the metal hook. Push the new fuel filter's nozzle firmly into the suction hose. Finally, refit the gas cap, air filter box, air filter, and filter cover before reusing the Stihl.

Re-attaching the fuel filter

To re-attach the fuel filter of your Stihl MS310, you will need to purchase a replacement fuel filter. You can find these online or at a hardware store.

Once you have your new fuel filter, follow these steps:

• Remove the old fuel filter: This will involve carefully detaching any hoses or connections that attach the filter to the fuel line. Be sure to do this over a drip pan or tray to catch any excess fuel.
• Clean the area: Before installing the new filter, ensure that the surrounding area is clean and free of debris.
• Attach the new fuel filter: Connect the new fuel filter to the fuel line, ensuring that all connections are secure and tight. Refer to the manufacturer's instructions or a repair manual for specific details on how to attach the filter.
• Check for leaks: Once the new filter is in place, check all connections for any signs of leakage. If there are no leaks, then you have successfully re-attached the fuel filter.

Remember to wear appropriate safety gear when performing any maintenance on your chainsaw, including eye protection and gloves. It is also important to work in a well-ventilated area when dealing with fuel and to dispose of any waste properly.

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