Changing a Machine Serpentine Belt

With the right tools, irresolute a drive belt is easier than yous think!

Time

An hour or less

Complexity

Beginner

Toll

$51–100

Introduction

Automated belt tensioners, standard in almost cars now, make changing a serpentine belt a elementary DIY repair. Follow the clear photos and step-by-step instructions and yous'll exist washed in 15 minutes.

Tools Required

Materials Required

  • Premium serpentine chugalug
  • Tensioner (if needed)

Overview: Fan belt replacement

If you're quondam enough to remember the good old days when you inverse your own fan belts, then y'all can likewise recall the bruised knuckles and cursing that went forth with information technology. And to make matters worse, there were ofttimes 2 or iii belts to modify.

Now, instead of separate belts for each component, most cars today utilize a single wider, multigrooved "serpentine" belt (aka every bit serp belt), named for the way information technology snakes effectually multiple pulleys.

Serpentine belt replacement is easy because today'south automatic drive belt tensioners eliminate the need to loosen bolts or pry components into position for retensioning. Just rotate the tensioner, remove the old belt and install a new one. When the belt ribs are seated into the pulley grooves, release the tensioner and yous're washed.

Project step-by-stride (11)

Step 1

Fan belt replacement: Check the tensioner first

tensioner

Check for excessive movement

A "good" tensioner arm should exhibit just a slight vibration with virtually ane/32 in. or less of arm movement. And the belt should run smoothly with no visible vibration. If the tensioner arm exhibits a jerky vibrating move, the belt vibrates, or the tensioning arm moves i/four in., the tensioner is bad.

How Many MPGs Are You lot Losing Running the Automobile Air conditioning?

Footstep 2

Check for polish rotation with a serpentine belt tool

Snap a long-handled ratchet or a serpentine belt tool into the foursquare 1/ii-in.-drive or 3/viii-in.-drive opening. Or use a socket on the hex-shaped protruding nut. Slowly rotate the tensioner arm as far equally it volition plough. Then release the tension. Experience for bounden and creaking in both directions.

100 Super-Simple Motorcar Repairs You Don't Need to Go to the Shop For

Step three

Check the pulley/roller

roller

Rotate the tensioner and slide the drive belt off the pulley/roller. Then turn the pulley/roller and feel for resistance, bounden and roughness. Then spin it and listen for rumbling. If information technology doesn't spin spin smoothly or has a rough surface, replace information technology.

If your tensioner is bad and it's i of the more than hard styles to supplant, you won't want to waste matter your time changing the belt. The shop would merely take to remove the belt again to supersede the tensioner. Then check the tensioner first with these three tests.

The showtime test is a visual inspection with the engine running to assess the dampening feature of the tensioner. Popular the hood, showtime the engine and turn on the AC. Then smooth a light on the belt tensioner and observe the tensioner arm roller for excessive move (Photo ane). If it passes the visual exam, motility on to the "creepo" test (Photograph 2). The tensioner arm should rotate smoothly during creepo and release with no binding. If the travel isn't smooth, replace the entire tensioner. Adjacent, check the condition of the tensioner arm pulley/roller (Photo 3). If the pulley or roller exhibits any roughness, binding or noise, that is also crusade to replace the entire tensioner.

Many tensioners are readily attainable and attach to the engine with a single commodities. To replace that way, just remove the serp belt and then the retaining bolt. Pull off the one-time tensioner, noting the location of the locking pivot on the back. Then slide the new unit into identify, lining up the locking pin with the pigsty in the engine. Hand-tighten the bolt so tighten it with a torque wrench to the mill specifications shown in your shop manual.

Step 4

How to tell if you lot need to exercise serpentine belt replacement

Measure out article of clothing with a guess

Press the gauge into a belt groove. As long as the estimate sits in a higher place the ribs, the belt is good. If information technology slides downwardly and so it's even with the rib, the serp chugalug is worn and must be replaced.

15 Machine Problems You Can Diagnose (and Set up!) Yourself

Pace 5

Measure wear with an app

Draw a line on the belt ribs with a silver permanent marker. So shoot a photograph with your smartphone. The app will tell y'all if the serp belt is good or bad.

First-generation serpentine belts were made from a nitrile chemical compound that cracked with utilize. If your drive belt has cracks in three or more adjacent ribs within a 1-in. span, or has four or more cracks per inch on a single rib, it's fourth dimension to replace it. You lot also need a new belt if you find whatever of these atmospheric condition: chunks missing from the rib area, torn or frayed fabric, glazing on the chugalug's back side or droppings trapped in the ribs.

Starting with the 2000 models, carmakers switched from nitrile to ethylene propylene diene monomer (EPDM) belts. EPDM belts last much longer and don't crack or lose chunks the way nitrile belts do. Only they exercise wearable, and that wearable is much harder to detect. You can measure EPDM belt wear with a approximate or a smartphone app. Both products are available for costless from Gates Corp. (go to gatesprograms.com/beltwear and click on either tool).

In most cases, you'll want to utilise the plastic judge to measure your belt, as shown in a higher place. However, if you have a smartphone and enough maneuvering room to shoot a close-up photo (engine off), let technology practise the work for yous. The app works past analyzing the width of the ribs compared with the width of the grooves.

Always buy premium belts instead of economy grade—y'all'll get almost twice the mileage.

100 Motorcar Maintenance Tasks You Can Exercise on Your Own

Footstep 6

The correct tools go far a practice-it-yourself projection

Follow the chugalug routing diagram

Examine the decal that shows the belt routing. If yours doesn't accept one, draw i earlier you lot first the job.

15 All-time Automotive Tools at Harbor Freight

Step 9

Place the new belt

belt

Using the serp belt placement tool, route the new belt effectually the belt path. Rotate the tensioner again while you load the chugalug around it. Wrap the new belt around the crankshaft caster, and then around the grooved pulleys. End the job past sliding the belt onto a rounded, non-grooved roller. Double-check to make certain the belt is aligned with all the pulleys and that information technology follows the correct path. Slowly release the tensioner.

xvi Things Your Mechanic Wants You to Stop Doing

Step 11

Serpentine belt tool and chugalug placement tool

tool

Cheap specialty tools greatly simplify changing the serpentine chugalug. You tin supersede a serpentine belt with ordinary hand tools. Simply we don't recommend it. The spaces are often tight and the chugalug-driven devices difficult to reach. Using a serpentine belt tool to loosen the tensioner and a belt placement tool to position the chugalug, we completed the unabridged job in less than 15 minutes, without breaking a sweat (or a knuckle). The serpentine belt tool comes with an array of sockets, making it the perfect choice for all the cars in your family. The two extension bars can be configured to reach the tensioner at the proper angle, and the extra-long handle provides maximum leverage and then you tin release the pressure easily. The belt placement tool allowed united states to remove and properly place the new belt without reaching downwards into the pulley surface area.

Note: If your motorcar requires the removal of an engine mount in order to remove the serpentine belt, or the chugalug'southward just nigh incommunicable to get at, we recommend you leave the task to a professional.

46 DIY Auto Detailing Tips That Volition Save You Money

Originally Published: May thirteen, 2019