The step-by-step instructions in this DIY lawn mower repair guide explain how to replace the front deck tray on a lawn mower. The front deck tray houses the transmission and wheel axle on a front-wheel drive lawn mower. The end of the drive cable attaches to an anchor post on the deck tray. If the anchor post breaks, the drive cable won't engage the transmission, and the mower won't move forward. Replace the front deck tray with the manufacturer-approved replacement part.
Use this procedure to replace the front deck tray transmission in common Craftsman and MTD walk-behind lawn mowers. A broken front deck tray is just one reason a lawn mower won't drive forward. To learn how to diagnose a lawn mower drive problem, see Lawn Mower Won't Move Troubleshooting Video: Motion Drive Failure.
This video explains how to replace the front deck tray on a walk-behind lawn mower.
Disconnect the spark plug wire
Disconnect the spark plug wire from the spark plug.
Disconnect the spark plug.
Remove the drive cover and front deck tray mounting screws
Pull the drive control lever up and clamp it to the mower handle to keep the drive belt tight as you remove the deck tray mounting screws.
Remove the fuel tank cap.
Place a plastic bag over the fuel tank opening and reinstall the fuel tank cap to prevent gasoline from leaking out through the fuel tank cap vent.
Remove the top drive cover mounting screws.
Tilt the mower back to lift the front wheels then secure the mower handle to your work table to hold the mower steady as you remove bottom-mounting screws.
Remove the bottom drive cover mounting screws.
Remove the front deck tray mounting screws.
Release the mower handle from the work table and carefully lower the mower to the upright position.
Remove the top drive cover screws.
Release the ground drive belt
Release the height adjuster lever and pull off the drive cover.
Remove the clamp from the drive control lever, letting the control lever drop to the disengaged position.
Pull off the transmission belt keeper.
Roll the ground drive belt off the transmission pulley.
Attach one end of the bungee cord to the drive belt and the other end to the rear discharge chute door lip to prevent the belt from slipping off the engine pulley while replacing the front deck tray.
Release the drive belt.
Release the drive control cable
Release the drive cable from the drive control lever.
Remove the drive cable end from the anchor post.
Depress the release tabs and pull the drive cable out of the transmission lever.
Release the drive cable.
Remove the front deck tray
Remove the transmission axle clip.
Pull the transmission and wheel axle up slightly then disconnect the tension spring pin from the transmission.
Remove the transmission and wheel axle.
Disconnect the tension spring pin from the front deck tray.
Remove the front deck tray.
Remove the transmission and wheel axle.
Install the new front deck tray
Install the tension spring pin on the new front deck tray.
Position the transmission and wheel axle above the front deck tray and reconnect the transmission to the tension spring pin.
Reinstall the transmission axle clip.
Release the drive belt from the bungee cord while you keep tension on the drive belt to prevent it from slipping off the engine pulley.
Reconnect the drive belt to the transmission then reinstall the belt keeper.
Push the drive cable into the transmission lever and engage the locking tabs.
Reconnect the drive cable end to the anchor post.
Reconnect the drive cable to the drive control lever on the lawn mower handle.
Use one hand to support the front deck tray and carefully tilt the mower back to raise the front of the deck along with the front deck tray. Make sure that the mower deck tabs engage the slots in the new front deck tray so that the deck tray lifts up with the deck when tilting the mower back.
Secure the mower handle to your work table to hold the mower steady as you reinstall the bottom-mounting screws.
Reinstall the front deck tray mounting screws.
Position the drive cover on the mower and re-engage the height adjuster lever.
Reinstall the bottom mounting screws in the drive cover.
Look through the opening in the debris shield to make sure the drive belt is still connected to the engine pulley. If the drive belt worked its way off the engine pulley during the repair, then follow the steps in the repair guide for drive belt replacement to reconnect the drive belt to the engine pulley.
Release the mower handle from the work table and tilt the mower upright.
Reinstall the drive cover top mounting screws.
Remove the plastic bag from the fuel tank opening and reinstall the fuel tank cap.
Install the tension spring.
Reconnect the spark plug wire
Push the spark plug wire back onto the spark plug.
These step-by-step repair guides will help you safely fix what’s broken on your walk-behind lawn mower.
Replace the ignition coil if it isn't sending electric current to the spark plug when you pull the recoil starter rope.
The flywheel key couples the flywheel to the engine crankshaft. Replace the flywheel key if it's broken.
The drive cable engages the transmission to spin the drive wheels and move the mower across the grass. Replace the drive cable if it's broken or frozen up inside the sheath.
Use the advice and tips in these articles and videos to get the most out of your walk-behind lawn mower.
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