Toro Lawn Mower Transmission Replacement, Mower Repair #121-9178

05:39
377k
625
This video provides step-by-step instructions for replacing the transmission on Toro lawn mowers. The most common reason for replacing the transmission is when the lawn mower wheels don’t turn.

All of the information in this transmission replacement video is applicable for the following brands: Toro.

Tools needed: socket wrench, snap ring pliers, wrench

Step By Step Instructions

1
Before you begin the repair, make sure the mower’s engine has cooled and remove the wire and boot from the spark plug.
2
Your first step is to carefully set the mower on its side.
3
Next, use a support to hold the blade in place.
4
Using a 5/8th inch socket, remove the mounting bolt and washer then pull off the blade adapter and blade.
5
Now use a half-inch socket to remove the upper bolt securing the belt guide and loosen the lower bolt.
6
Move the guide out of the way, unthread the belt and pull off the blade driver.
7
Your next step is to remove the bolts from the deck to release both the belt shield and the rear baffle. Be aware you may need to readjust the wheels to access certain bolts.
8
With the bolts removed, set the shield and the baffle aside.
9
Adjust the traction cable tension if necessary and remove the spring end of the cable from the transmission bracket.
10
Rotate the transmission and remove the screws to release the transmission bracket.
11
Remove the old belt from the pulley.
12
Now carefully set the mower upright and support it.
13
Use a half-inch socket to remove the bolts to release both rear wheel assemblies and debris shields.
14
Use snap-ring pliers to remove the snap rings from the transmission shaft then pull off the gears and washers.
15
Now hold the transmission shaft as you set the mower back on its side.
16
Use a half-inch wrench to secure the adjustment plate mounting nuts while you use a half-inch socket to unthread the two bolts and remove them.
17
Slide the old transmission up, lift the plate out of the way and pull the transmission out. Be aware this may require some effort. You’re now ready to install the new transmission.
18
Lift up the deck adjustment plate and slide the new transmission into place.
19
Replace the mounting bolts.
20
Thread the nuts onto the bolts and tighten with the wrench and socket.
21
Set the mower upright and support it then replace the washers, gears and snap rings onto the transmission shaft.
22
Reinstall the two rear wheels by first inserting the bolts and positioning the debris shields.
23
Then align the bolts with the mounting brackets and thread the bolts into place.
24
Tighten them with the socket.
25
Remove the support and set the mower back on its side.
26
Thread the belt onto the pulley then replace the transmission bracket and secure the screws.
27
Rotate the transmission into place and reattach the spring end of the traction cable to the transmission bracket.
28
Align the belt shield with the rear baffle and reinstall by securing the bolts.
29
Make sure to readjust the wheels to the desired position.
30
Now, align the key on the blade driver with the keyway in the shaft and slide the driver into place.
31
Thread the belt and reposition the belt guide.
32
Reinstall the upper bolt and tighten the lower one.
33
Next, insert the bolt and washer through the blade adapter and blade.
34
Position the assembly onto the blade driver and use the support to hold the blade in place.
35
Thread the bolt and torque the bolt to 60 foot pounds. Be aware this may require some effort.
36
Remove the support and carefully set the mower upright.
37
With the repair complete, you can now reattach the spark plug wire and boot.
Description
This video provides step-by-step instructions for replacing the transmission on Toro lawn mowers. The most common reason for replacing the transmission is when the lawn mower wheels don’t turn.

All of the information in this transmission replacement video is applicable for the following brands: Toro.

Tools needed: socket wrench, snap ring pliers, wrench
Step-By-Step Instructions
1
Before you begin the repair, make sure the mower’s engine has cooled and remove the wire and boot from the spark plug.
2
Your first step is to carefully set the mower on its side.
3
Next, use a support to hold the blade in place.
4
Using a 5/8th inch socket, remove the mounting bolt and washer then pull off the blade adapter and blade.
5
Now use a half-inch socket to remove the upper bolt securing the belt guide and loosen the lower bolt.
6
Move the guide out of the way, unthread the belt and pull off the blade driver.
7
Your next step is to remove the bolts from the deck to release both the belt shield and the rear baffle. Be aware you may need to readjust the wheels to access certain bolts.
8
With the bolts removed, set the shield and the baffle aside.
9
Adjust the traction cable tension if necessary and remove the spring end of the cable from the transmission bracket.
10
Rotate the transmission and remove the screws to release the transmission bracket.
11
Remove the old belt from the pulley.
12
Now carefully set the mower upright and support it.
13
Use a half-inch socket to remove the bolts to release both rear wheel assemblies and debris shields.
14
Use snap-ring pliers to remove the snap rings from the transmission shaft then pull off the gears and washers.
15
Now hold the transmission shaft as you set the mower back on its side.
16
Use a half-inch wrench to secure the adjustment plate mounting nuts while you use a half-inch socket to unthread the two bolts and remove them.
17
Slide the old transmission up, lift the plate out of the way and pull the transmission out. Be aware this may require some effort. You’re now ready to install the new transmission.
18
Lift up the deck adjustment plate and slide the new transmission into place.
19
Replace the mounting bolts.
20
Thread the nuts onto the bolts and tighten with the wrench and socket.
21
Set the mower upright and support it then replace the washers, gears and snap rings onto the transmission shaft.
22
Reinstall the two rear wheels by first inserting the bolts and positioning the debris shields.
23
Then align the bolts with the mounting brackets and thread the bolts into place.
24
Tighten them with the socket.
25
Remove the support and set the mower back on its side.
26
Thread the belt onto the pulley then replace the transmission bracket and secure the screws.
27
Rotate the transmission into place and reattach the spring end of the traction cable to the transmission bracket.
28
Align the belt shield with the rear baffle and reinstall by securing the bolts.
29
Make sure to readjust the wheels to the desired position.
30
Now, align the key on the blade driver with the keyway in the shaft and slide the driver into place.
31
Thread the belt and reposition the belt guide.
32
Reinstall the upper bolt and tighten the lower one.
33
Next, insert the bolt and washer through the blade adapter and blade.
34
Position the assembly onto the blade driver and use the support to hold the blade in place.
35
Thread the bolt and torque the bolt to 60 foot pounds. Be aware this may require some effort.
36
Remove the support and carefully set the mower upright.
37
With the repair complete, you can now reattach the spark plug wire and boot.

Applicable Product Model

Parts Needed
Recommended Tools and Accessories
Fuel Tank
Fuel Tank
$29.18
Fuel Tank
Fuel Tank
$46.58
Total$0.00

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