Video & Articles: Appliance & Equipment RepairKohler Twin-Cylinder Small Engine Flywheel Key #X-42-15-S

Kohler Twin-Cylinder Small Engine Flywheel Key #X-42-15-S

07:09
This video provides step-by-step instructions for replacing the flywheel key on single cylinder Kohler Command small engines, commonly found on riding lawn mowers, riding tractors, zero-turn radius mowers, and commercial walk-behind mowers. The most common reasons for replacing the flywheel key are when the engine won’t start or is hard to start and the flywheel key is damaged.

All of the information in this flywheel key replacement video is applicable to the following brands: Kohler, Exmark, Toro, John Deere

Tools used: socket wrench, strap wrench, hammer, puller

Step By Step Instructions

1
Before you begin this repair, make sure the engine has cooled remove the wire and boot from the spark plug or plugs
2
Then disconnect the cables from the battery; black first, then red.
3
Now loosen the cover knob securing the air filter cover and pull the cover off.
4
Remove the screws to release the regulator/rectifier.
5
Now remove the retaining bolts securing the blower housing and pull the housing off.
6
Next, unsnap the grass shield and remove.
7
Use a socket to remove the screws securing the fan assembly and pull the assembly off.
8
Next, you will need to stabilize the flywheel. You can use a strap wrench to do this.
9
Have an assistant hold the flywheel in place then position a socket on the retaining bolt and strike it with a hammer to loosen. This will probably require some effort.
10
Remove the bolt and washer.
11
Now use a puller to detach the flywheel from the shaft.
12
Remove the puller and the strap wrench.
13
You will now need to remove the ignition coil.
14
Remove the bolts securing the coil and move the coil out of the way.
15
Now lift the flywheel off.
16
If still intact, remove what’s left of the old flywheel key.
17
Install the new flywheel key by inserting it into the crankshaft and tapping it into place.
18
Reposition the flywheel by aligning the slot in the flywheel with the new key and sliding it onto the crankshaft.
19
Reinsert the retaining bolt and washer then torque the bolt to manufacturer specifications.
20
Now reposition the ignition coil and insert the mounting bolts.
21
Pull the coil back and tighten the bolts.
22
Now, rotate the flywheel so the magnets align with the coil.
23
Insert a business card and loosen the bolts to align the coil the correct distance from the flywheel.
24
Re-tighten the bolts and remove the business card.
25
Replace the fan assembly and secure the screws.
26
Snap the grass shield back into place.
27
Reposition the blower housing and secure the retaining bolts.
28
Align the regulator/rectifier on the blower housing along with the grounding wire if applicable and secure with the mounting screws.
29
Replace the air filter cover and tighten the cover knob.
30
You can now reconnect the battery cables red first, then black.
31
Finally, reattach the wire and boot to the spark plug or plugs.
Description
This video provides step-by-step instructions for replacing the flywheel key on single cylinder Kohler Command small engines, commonly found on riding lawn mowers, riding tractors, zero-turn radius mowers, and commercial walk-behind mowers. The most common reasons for replacing the flywheel key are when the engine won’t start or is hard to start and the flywheel key is damaged.

All of the information in this flywheel key replacement video is applicable to the following brands: Kohler, Exmark, Toro, John Deere

Tools used: socket wrench, strap wrench, hammer, puller
Step-By-Step Instructions
1
Before you begin this repair, make sure the engine has cooled remove the wire and boot from the spark plug or plugs
2
Then disconnect the cables from the battery; black first, then red.
3
Now loosen the cover knob securing the air filter cover and pull the cover off.
4
Remove the screws to release the regulator/rectifier.
5
Now remove the retaining bolts securing the blower housing and pull the housing off.
6
Next, unsnap the grass shield and remove.
7
Use a socket to remove the screws securing the fan assembly and pull the assembly off.
8
Next, you will need to stabilize the flywheel. You can use a strap wrench to do this.
9
Have an assistant hold the flywheel in place then position a socket on the retaining bolt and strike it with a hammer to loosen. This will probably require some effort.
10
Remove the bolt and washer.
11
Now use a puller to detach the flywheel from the shaft.
12
Remove the puller and the strap wrench.
13
You will now need to remove the ignition coil.
14
Remove the bolts securing the coil and move the coil out of the way.
15
Now lift the flywheel off.
16
If still intact, remove what’s left of the old flywheel key.
17
Install the new flywheel key by inserting it into the crankshaft and tapping it into place.
18
Reposition the flywheel by aligning the slot in the flywheel with the new key and sliding it onto the crankshaft.
19
Reinsert the retaining bolt and washer then torque the bolt to manufacturer specifications.
20
Now reposition the ignition coil and insert the mounting bolts.
21
Pull the coil back and tighten the bolts.
22
Now, rotate the flywheel so the magnets align with the coil.
23
Insert a business card and loosen the bolts to align the coil the correct distance from the flywheel.
24
Re-tighten the bolts and remove the business card.
25
Replace the fan assembly and secure the screws.
26
Snap the grass shield back into place.
27
Reposition the blower housing and secure the retaining bolts.
28
Align the regulator/rectifier on the blower housing along with the grounding wire if applicable and secure with the mounting screws.
29
Replace the air filter cover and tighten the cover knob.
30
You can now reconnect the battery cables red first, then black.
31
Finally, reattach the wire and boot to the spark plug or plugs.

Applicable Product Model

Parts Needed
Recommended Tools and Accessories
Fuel Tank
Fuel Tank
$31.52
Fuel Tank
Fuel Tank
$54.38
Total$0.00

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