Maintain a MTD Yard Machine Garden Tractor Fuel Tank
Introducing a procedure to maintenance the Fuel Tank Assembly in a MTD Yard Machine Lawn Tractor Model 84A (840-series #14AS84AH062) equipped with an 18.5hp Briggs and Stratton air-cooled engine. The following article describes those steps necessary for the disassembly, removal, servicing, and re-installation of the components.
- Read some of the directions in Maintenance a MTD Yard Machine Lawn Tractor and perform SECTION G: STEPS #01 - #15 contained therein. Only when fully completed proceed with those steps shown below.
- Remove the fuel line hose clamp with a 3/8" wrench or ratchet/socket. Remove the 1/4" x 1/2" hex screw holding both the Fuel Line Clamp (Retainer) and one side of the Fuel Tank Strap. Once the screw has been removed, remove the Fuel Line Hose Clamp by simply slipping the expandable clamp off of the Fuel Line.
- Disconnect the fuel line intake clamp. Gently squeeze the opposing tabs on the yellow Fuel Line Intake Clamp with a pair of regular pliers and slide it a couple of inches down the Fuel Line just far enough for it not to be a hindrance to removing the Fuel Line.
- Remove fuel intake. The fuel intake assembly is press-fitted into the Fuel Tank making use of a rubber-seal fitting. The assembly is removed by simply grasping the metal elbow fitting on the Intake and gently pulling outwards.
- WARNING! Once the Intake has been removed, dangerous fuel vapors will begin escaping from the Fuel Tank. Use a clean, dry rag to plug the hole until the Intake has been disconnected from the Fuel Line and subsequently reinserted back into the tank.
- Disconnect the fuel intake from the intake assembly. Use a gentle twist-pull action while slowly working the rubber hose off of the "barbed" metal elbow-fitting.
- CAUTION! When removing the Fuel Line be aware that fuel may still be present in the hose. Use caution when disconnecting the Fuel Line from the elbow-fitting!
- IMPORTANT: Once the intake has been disconnected from the Fuel Line, re-insert the assembly back into the tank by pressing the rubber-fitting into the hole.
- Remove the fuel tank. The fuel tank is freely mounted in a "saddle" situated between the two chassis rails, thus allows the tank to be simply lifted out. Once removed, carefully empty any remaining contents of the tank into a suitable container to be properly disposed of.
- CAUTION! Even though the tank has either been siphoned or allowed to run dry, there is a high-risk that fuel and "bilge" remains in the bottom of the tank...use caution when removing the unit. This "bilge" in many instances is a leading cause to carburetor failure resulting in a costly tear-down and rebuild.
- Service the fuel tank. The MTD fuel tank on this yard tractor is a single-piece plastic composite tank designed to withstand the punishments of outdoor yard maintenance. When servicing the tank itself remember the following:
- Clean the tank with mild detergents, or those solutions designed specifically for removing contaminants from such tanks.
- During the cleaning process, do not install the tank gauge nor the fuel intake assembly. These must be serviced separately.
- After completion of the cleaning process, thoroughly rinse out the tank so as to remove all detergents, preventing fuel contamination.
- After completion of the rinsing process, allow the tank to fully dry before re-installation.
- Allow only minimal time once the tank has dried and inspections have been completed to reinstall the Fuel Gauge and Fuel Intake in order to prevent contaminants from entering the fuel system.
- Prior to beginning re-installation, thoroughly inspect the tank especially the manufacturing seams and the base of the nozzle neck for signs of splitting or cracks. If any are found, the tank MUST BE replaced!
- Carefully inspect the fuel gauge to insure that there are no cracks in the needle-dome or the the threaded neck which goes down over the tank nozzle.
- Carefully inspect the gasket on the underside of the gauge to insure that there are no cracks or dry-rotting. If found, the gasket or the entire gauge must be replaced.
- Carefully inspect the fuel intake assembly to insure there is no splitting, cracking, or dry-rotting of the rubber seal that seats down into the fuel tank. If found, the intake will require replacement.
- Re-install the fuel gauge. Install the fuel gauge into the fuel tank to prevent contamination of the fuel system.
- Reinstall the fuel tank. Re-seat the tank down onto the fuel tank strap, insuring that the tank is firmly and correctly placed back into its "saddle" to prevent it from shifting.
- Reconnect the fuel intake. Reconnect the fuel intake assembly to the fuel line using a gentle twist-push action while slowly working the rubber hose onto the "barbed" metal elbow-fitting.
- Re-install the fuel intake. The fuel intake assembly is press-fitted into the fuel tank making use of a rubber-seal fitting. The assembly is installed by simply grasping the metal elbow fitting on the Intake and gently pushing it into the Fuel Tank.
- Re-connect the fuel line intake clamp by gently squeezing the opposing tabs on the yellow fuel line intake clamp with a pair of regular pliers and slide the clamp back snug against the metal fuel intake assembly elbow-fitting.
- Re-install the fuel line clamp. Gently reinstall the Fuel Line Clamp back onto the Fuel Line with the flat-side of the clamp DOWN! Then, with a 3/8" wrench or ratchet/socket, reinstall the 1/4" x 1/2" hex screw holding both the Fuel Line Clamp and the right-side of the Fuel Tank Strap.
- Research How to Maintain a MTD Yard Machine Lawn Tractor and perform SECTION G: STEPS #01 - #15...
- Refuel the tank with fresh, non-ethanol, unleaded-gasoline and start the engine. If fuel had been allowed to drain from the fuel line it may take a few cracks for the motor to fire. You can also use starting-fluid (Ether) with caution to help the engine prime the fuel line, fuel filter, and the fuel-pump (carburetor).
- Keep work surfaces clean, clear of debris, and free of obstructions to prevent loss of parts or tools in the event they are inadvertently dropped.
- After reassembly and prior to starting the engine, check and recheck all work that has been performed and insure that all safety precautions are in place.
- Make use of Nitrile, Latex, or some type of work-gloves that will prevent fuel, oil, and contaminants from coming into contact with your skin.
- Maintain a workspace around the machine that allows access to the equipment from all sides while it is being serviced.
- After reassembly, allow the engine to idle for a short-period of time and then begin moving the throttle upwards to insure that proper fuel-flow is achieved. If engine performance is satisfactory, then take the necessary steps to test the engine under load by engaging the PTO (mowing deck).
- During disassembly, utilize a method for arranging, bagging, and tagging parts to insure proper reassembly.
- After reassembly, starting of the engine may be difficult if fuel has been allowed to drain from the fuel line and the carburetor. Have a can of starting-fluid (Ether) handy to help get the fuel line, fuel-filter, and the carburetor primed.
- Prior to work: Disconnect the battery terminals and insulate them from potential electrical discharges.
- Prior to work: Insure that the unit is not hot and is cool to the touch.
- Gasoline is a highly-flammable liquid with a low flash-point! Adhere to all safety precautions when servicing the machine.
- Do not allow children or animals in or around the work-area.
- Prior to work: Insure the work-area free of combustible materials.
- While servicing the machine, especially in low-humidity, ensure that you are properly grounded to eliminate possible electrical static discharge.
- Prior to work: Insure that a fire extinguisher properly rated for flammable liquids is readily available in the work-area.
- Perform service work only in a well-ventilated area.
- Adhere to and abide by all safety concerns and precautions specified by the OEM which takes precedence over this wikiHow.
- Prior to work: Insure that proper safety equipment is worn at all times and is in good-working condition.
- Prior to work: Drain any remaining fuel from the tank.
- Gasoline is a known carcinogen and can be directly absorbed through the skin or inhaled! Use of Personal Protection Equipment (PPE) in correct working condition is highly recommended.
- Use only high quality unleaded-grade gasoline in this type engine to insure its top performance. Verify that the fuel is fresh, clean, and free of contaminates before using. Do NOT use Ethanol-enriched or any other alcohol-enhanced fuels in this engine.
Things You'll Need
- Wrench: 3/8"
- Socket: 3/8"
- Maintain a MTD Yard Machine Garden Tractor Fuel Tank
- MTD OWNERS GUIDE : Publication #770-8552M
- MTD SERVICE GUIDE: Publication #770-10579
- MTD ILLUSTRATED PARTS LIST (IPL): http://www.mtdparts.com/