Horizon
Treadmill

Model #QUANTUM II Horizon treadmill

Here are the diagrams and repair parts for Horizon QUANTUM-II treadmill, as well as links to manuals and error code tables, if available.


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Showing 10 of 143 parts

Deck Exten

#B55

Treadmill assembly Diagram

Deck exten

Part #000819-00
?
Manufacturer substitution
This part replaces MB0603001. Substitute parts can look different from the original.
This part replaces MB0603001
This item is not returnable
$2.16

In Stock

Nylon Nut

#L09

Treadmill assembly Diagram

Nylon nut

Part #004949-00
?
Manufacturer substitution
This part replaces ME0204034. Substitute parts can look different from the original.
This part replaces ME0204034
This item is not returnable
$2.16

In Stock

Belt Guide

#B34

Treadmill assembly Diagram

Belt guide

Part #007526-D
?
Manufacturer substitution
This part replaces MJ1060004C. Substitute parts can look different from the original.
This part replaces MJ1060004C
This item is not returnable
$3.47

In Stock

Bolt

#B41

Treadmill assembly Diagram

Bolt

Part #008609-00
?
Manufacturer substitution
This part replaces MJ3011001. Substitute parts can look different from the original.
This part replaces MJ3011001
This item is not returnable
$5.93

In Stock

Bolt

#C08

Treadmill assembly Diagram

Bolt

Part #MZE0112072

The manufacturer no longer makes this part, and there's no substitute part

Exercise Equipment Retainer Clip

#N43

Treadmill assembly Diagram

Exercise equipment retainer clip

Part #005330-00
?
Manufacturer substitution
This part replaces MZE0701001. Substitute parts can look different from the original.
This part replaces MZE0701001
This item is not returnable
$2.16

In Stock

Washer

#B46

Treadmill assembly Diagram

Washer

Part #MZE0502054

The manufacturer no longer makes this part, and there's no substitute part

Exercise Equipment Screw

#R04

Treadmill assembly Diagram

Exercise equipment screw

Part #004486-00
?
Manufacturer substitution
This part replaces MZE0104203. Substitute parts can look different from the original.
This part replaces MZE0104203
This item is not returnable
$3.07

In Stock

Screw

#B36

Treadmill assembly Diagram

Screw

Part #MZE0105013

The manufacturer no longer makes this part, and there's no substitute part

Exercise Equipment Washer

#K11

Treadmill assembly Diagram

Exercise equipment washer

Part #000491-B
?
Manufacturer substitution
This part replaces MB0302002. Substitute parts can look different from the original.
This part replaces MB0302002
This item is not returnable
$2.55

In Stock

Symptoms for treadmills

Choose a symptom to see related treadmill repairs.

Main causes: damaged walking belt, improper belt tension, lack of belt lubricant, bad drive motor
Main causes: faulty sensors, wiring failure, bad control console
Main causes: missing safety key, bad control console, wiring failure, faulty motor control board, bad drive motor
Main causes: rear roller out of alignment, damaged walking belt, bad roller
Main causes: no power, bad power cord, tripped or faulty overload switch, bad power switch, wiring failure, bad motor control board
Main causes: bad control console, wiring failure, bad motor control board
Main causes: damaged walking belt, improper belt tension, bad roller bearing

Repair guides for treadmills

These step-by-step repair guides will help you safely fix what’s broken on your treadmill.

June 1, 2015
By Lyle Weischwill
How to replace a treadmill drive motor

A defective drive motor won't run when activated by the motor controller. Replace the treadmill drive motor if it doesn't run.

Repair difficulty
Time required
 15 minutes or less
June 1, 2015
By Lyle Weischwill
How to replace a treadmill motor controller

Your treadmill motor won't run with a defective motor controller. Replace the motor controller if it doesn't operate the motor correctly.

Repair difficulty
Time required
 15 minutes or less
June 1, 2015
By Lyle Weischwill
How to replace a treadmill walking board

A worn-out walking board creates friction with the walking belt and causes the belt to slow down during use. Replace the walking board if it's worn or damaged.

Repair difficulty
Time required
 30 minutes or less

Articles and videos for treadmills

Use the advice and tips in these articles and videos to get the most out of your treadmill.

January 18, 2016

How to use a multimeter to test electrical parts video

By Sears PartsDirect staff

Learn how to use a multimeter to check for wiring problems in an appliance that's not working

June 29, 2015

Easy DIY treadmill repairs

By Sears PartsDirect staff

Learn about treadmill repairs that you can easily do yourself.

June 1, 2015

Treadmill common questions

By Sears PartsDirect staff

These answers to common questions can help you make the most of your treadmill.