When the motor drive belts in your Troy-Bilt Model 77 mower provide out, the only means to get it running again would be to replace them with fresh ones. Replacing the belts in this two-belt system requires you to dismantle and reassemble several parts of the mower so as to remove the old straps and install the new ones. By staying organized as you work and ensuring that you have the correct tools and instructions, you will be able to efficiently replace both belts on your mower.
Park the mower on a flat surface and remove the key from the ignition. This prevents accidental starting of the machine during the repair.
Fix the deck lift lever, found on the ideal fender, to the bottom position. Use the appropriate socket to remove nuts which hold the belt guard set up. Pull the belt guard from the machine and disconnect the mower deck belt from the pulley beneath the back of the machine.
Use a pair of needle-nose pliers to remove the two back pins that attach the deck lift linkage into the mower deck. Pull the elevator linkage away from the deck. Remove the pin which holds the front deck lift linkage into the mower and pull the elevator linkage away from the deck. Pull the pin that attaches the PTO cable into the mower deck with the needle-nose pliers, and pull the PTO cable loose from its housing. The cable is still connected to the deck with a huge spring. Grasp the spring and twist it to remove it from the deck. Now that the deck is completely detached from the mower, then roll it out from underneath the machine and place it aside.
Lift the battery cover in the back of the machine to get the mower’s battery. Use two wrenches, one in each hand, to remove the negative battery cable from the battery’s terminal. Hold the bolt stable with one wrench while you twist the washer free from the finish. Repeat this procedure to remove the positive battery cable.
Press on one end of this bar that is over the battery and holds it in place to take out the bar. Lift the battery from the machine and place it aside. Remove the two battery support bars which sit beneath the battery by pulling the ends of these from the slots to which they’re inserted.
Tie a piece of cord around the end of the idler spring which you can see protruding underneath the battery compartment. Bend the ends of the string together to form a loop. Pull firmly on the string to dislodge the end of the idler spring and remove it from the mower.
Insert a screwdriver to the head of the bolt which holds the transmission pulley set up. Hold the screwdriver firm and take out the transmission pulley nut by turning it with a wrench in precisely the same time. Pull the pulley from the spindle on which it sits and disconnect the top motor belt from the pulley.
Find the belt which runs from the mower’s engine and wraps around a pulley in the back of the machine. Hold the pulley’s spindle in place with a pipe wrench and remove the nut underneath the pulley with the appropriate socket connected to the socket. Pull the pulley from the machine. The belt will remain attached to this variable speed disc. Lift the center section of this pulley up and get rid of the belt.
Install the lower drive belt which runs from the engine to the transmission by wrapping it about the variable speed disc. Lift up the center section of this pulley again as you did when you removed the old one to install the new one. Slot both sides of the belt between the pulley and the guides that hold it in place. Reattach the engine pulley into the machine and secure it in place by reinstalling the middle nut. Wrap the belt around the engine pulley and add it between the spindle and the guides.
Wrap the top belt around the transmission pulley. Match the tooth of the pulley and the hub together with each other before tightening the nut that attaches the two. Wrap the belt around the top section of this variable speed pulley and about the idler pulley. Reattach 1 end of the idler spring into the frame of the mower. Wrap the cord you used previously around the opposite end of the spring, pull it across the hole from where you removed it earlier, and pull hard to reinsert the spring to the hole. Remove the cord when completed.
Reinstall the battery service bars which sit beneath the battery by inserting the protrusions at either end into the slots in the battery compartment. Place the battery back into the compartment under the service bars. Reinstall the pub over the battery which holds it in place. Reattach the positive battery cable to the positive battery terminal and bolt it in place. Repeat the procedure with the negative battery cable. Close the battery compartment cable.
Slide the mower deck back underneath the mower. Reattach the spring in the conclusion of this PTO cable into the mower’s deck. Pull the cable through the manual to make certain that it’s properly set up and reinsert the pin which holds it into the machine. Reconnect the lift linkage into the mower and add the pin which secures it. Repeat this procedure with the two back lift linkages.