The starter on my John Deere LX172 lawn mower finally gave up the ghost. Here is a quick and easy picture guide for replacing the starter on this lawn tractor. I’ve included photos of the steps as well as the socket sizes needed for all the nuts and bolts, I hope this helps make this job go a little quicker for someone out there!

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Tools Used for this Repair:

Required Parts:

How to Replace the Starter on a John Deere Lawn Tractor

Here is a quick summary of the steps, I go into more detail with the photos below, but sometimes it is good to have a summary with the nut and bolt sizes:

  1. Turn the key to the “off” position.
  2. Open the hood of the lawn mower.
  3. Remove the negative battery terminal.
  4. Locate the starter and disconnect the wiring harness by pressing the plastic tab and pulling it off.
  5. Disconnect the battery cable going to the solenoid using a 14mm socket.
  6. Remove the 2 starter mounting bolts (12mm).
  7. Slide the starter off of the engine.
  8. If you are only replacing the solenoid, remove the two 10mm nuts to remove it and swap with the new solenoid.
  9. Put the new starter on by reversing the steps.

Step by Step Instructions for Changing the Starter on a Lawn Mower

The unit I am working on is a John Deere LX172. Here it is with the hood already removed.

John-Deere-LX172-Lawn-Tractor

Turn the key to the ‘off’ position and raise the hood.

Here is a closer view of the Kawasaki engine.

John-Deere-LX172-Lawn-Tractor-Engine

Disconnect the negative battery terminal.

Locate the starter. This is a closer view of the starter location.

John-Deere-LX172-Lawn-Tractor-Starter-Solenoid

Disconnect the plastic wiring harness. It has a clip you should press, then pull it down and off.

Remove the positive battery cable using a 14mm socket or wrench.

John-Deere-Starter-Solenoid-Connections

Remove the two 12mm mounting bolts from the top of the starter. Slide the starter down and away from the engine.

John-Deere-LX172-Lawn-Tractor-Starter-Installation

Here is a picture of the starter once it is removed.

The part number for the new starter is 21163-2073, and here is the link:

Starter & Alternator Replacement For John Deere Lawn Tractors 170, 175, 240, 245, Kawasaki 14HP

John-Deere-LX172-Lawn-Tractor-Starter

Make sure you order the correct starter.

John-Deere-Lawn-Tractor-Starter-Motor

The correct starter for my tractor was the 21163-2073, which is stamped on the original:

John-Deere-Lawn-Tractor-Denso-Model

I mistakenly ordered the wrong on originally. Here is a photo of the original starter (top) alongside the incorrect starter (bottom):

John-Deere-Lawn-Tractor-Starter-Comparison

The starters look the same from the bottom. The main difference is the mounting hole spacing, and the fitment ring which is too big on the lower one in the picture.

For reference, the starter I needed was the 21163-2073.

The incorrect starter for me (bottom one in the picture) was this style.

If you only need to replace the solenoid, remove the two 10mm mounting nuts, and the 14mm grounding nut at the bottom. The correct solenoid is this one:

John Deere Replacement Solenoid

Here are some photos of the solenoid.

John-Deere-Lawn-Tractor-Solenoid

John-Deere-Lawn-Tractor-Solenoid-Connections

The solenoid removed from the starter:

John-Deere-Lawn-Tractor-Solenoid-Engagement

With the rubber shroud:

John-Deere-Lawn-Tractor-Solenoid-Engagement-Rubber

To put on the new starter, reverse the steps described.

I hope this helped save you some time and effort!

Rich

Replacement Parts and Tools: