2078118 Pulley As-Idler for CAT 966H, 972H, 980C & more
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Description for 2078118 Pulley
▶Specification for 2078118 Pulley
▶Exact Fit Guarantee for 2078118 Pulley
▶| Models | 966H, 972H, 980C, 980K, 980M, 982M, AP555E, BG500E, C11, C13, C7, C9, CX31-C13I, D8N, TH31-E61, TH35-C11I, TH35-C13I, TH35-C13T |
|---|---|
| Dimensions | 3.74x3.74x3.74 |
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Original Review (Spanish)
Si necesitas piezas de repuesto a buen precio para tu m?quina grande y quieres un servicio al cliente atento, esta tienda es una muy buena opci?n.
English Translation
If you need affordable replacement parts for your heavy equipment and want attentive customer service, this store is a very good option. -
When I had questions, they were answered quickly and kindly.
Thank you!! -
rapid response!
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Great Customer Service!
Had some difficulties with the website. Contacted customer service. Once I communicated the issues I was having Steven worked through getting my order processed and making sure I got my receipt and all issues resolved. Perfect! -
Having issue running my credit card, Steven was more than helpful to send me a payment link to complete my transaction!
Frequently Asked Questions
What is the function of the 2078118 idler pulley assembly?
The 2078118 idler pulley assembly helps guide and maintain proper tension on drive belts within engine accessory systems. It ensures belts stay aligned and operate smoothly, which supports consistent performance of components like alternators, pumps, and air conditioning systems.
How do I install the 2078118 idler pulley assembly?
Here’s a general guide for proper installation:
- Turn off the machine and ensure it is safely supported before beginning work.
- Relieve belt tension using the appropriate tool and remove the drive belt from the old pulley.
- Remove bolts or fasteners securing the old idler pulley assembly.
- Clean the mounting surface and inspect for any wear or damage.
- Install the new 2078118 idler pulley assembly and tighten fasteners to the recommended torque.
- Reinstall the belt and adjust tension as needed.
- Start the engine and check to confirm smooth belt operation.
Which machines or systems use the 2078118 idler pulley assembly?
The 2078118 idler pulley assembly is used in a range of heavy equipment engines where this part number is specified for accessory drive systems. Compatibility depends on your machine’s model and setup, so verify fitment using your equipment’s service documentation before ordering. Please reach out to Propel Parts for help verifying fitment.
Does the 2078118 idler pulley assembly meet performance expectations?
Yes, the 2078118 idler pulley assembly is engineered to meet or exceed OEM specifications for strength, durability, and smooth rotational action. When replacing pulley components, choose genuine or high-quality aftermarket parts that meet or exceed OEM expectations to help ensure reliable performance and long service life.
How often should an idler pulley assembly like the 2078118 be inspected or replaced?
Idler pulley assemblies should be checked during routine maintenance or whenever a drive belt is serviced. Inspect for signs of wear, noise, or rough rotation. If the pulley shows bearing noise, wobble, or surface wear, replace it promptly to prevent belt slippage or drive system issues.
What are common signs that the 2078118 idler pulley assembly needs replacement?
Typical indicators include:
- Squealing or chirping noises from the belt area
- Visible wear or grooves on the pulley surface
- Belt misalignment or slipping
- Vibration or wobbling during operation
Why is using a quality idler pulley assembly important for equipment performance?
A quality idler pulley assembly helps maintain proper belt alignment and tension, which supports efficient operation of driven accessories and reduces premature wear. Using genuine or high-quality aftermarket parts that meet or exceed OEM expectations helps enhance reliability, reduce downtime, and extend the life of belts and related components.
This 2078118 Pulley is compatible with the following models:
966H, 972H, 980C, 980K, 980M, 982M, AP555E, BG500E, C11, C13, C7, C9, CX31-C13I, D8N, TH31-E61, TH35-C11I, TH35-C13I, TH35-C13T & more...

We know equipment downtime costs money, so fast and reliable shipping is a priority at Propel Parts. Orders placed on weekdays before 3:00 PM ET typically ship the same day, with expedited delivery options available for many locations when time is critical.
We ship across the U.S., Canada, and over 130 countries worldwide, helping customers keep machines running wherever they operate. Available shipping methods and delivery estimates are shown at checkout so you can select the option that best fits your timeline.
Tracking information is emailed within 24–48 hours after your order is processed, giving you full visibility from dispatch to delivery and peace of mind that your parts are on the way.

Our refund policy is simple. We offer a 30-day, no-hassle return policy, and we make every effort to provide the best service and highest-quality parts possible. If you’re not fully satisfied with your purchase, you may return it within 30 days for a refund. Full details are available on our Returns Policy page.

Buy with confidence. All parts from Propel Parts are covered against material or manufacturer defects for 12 months from the original invoice date. We stand behind every part we sell, so you can count on reliable performance and dependable support. Full details are available on our Warranty Policy page.
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