AfterMarketNews Auto Care Pro AutoProJobs Auto-Video.com Brake&Frontend BodyShopBusiness Counterman EngineBuilder Fleet Equipment ImportCar Motorcycle & Powersports News Servicio Automotriz Shop Owner Tire Review Tech Shop Tomorrow's Tech Underhood Service

Second-rate parts mean second-rate results

When it comes to diagnosing a problem, one of the biggest mistakes is thinking that the problem is gone after you’ve installed a new part. I’ve had vehicles brought in countless times with the same old story attached to them. The customer will say:...

Read more...

GearWrench Launches Street Team, a New Mobile Driver Program

GearWrench, a premier hand tool brand from Apex Tool Group, has announced Street Team, a new program that gives independent mobile distributors the support of an established tool brand without the restrictions of a franchise. "Response to the program...

Read more...

AUTO 7 Named Approved Vendor For Automotive Parts Associates

Steven Kruss, president of Auto 7, which supplies Korean-made, OEM-quality automotive parts to distributors across North America, announced that Auto 7 has been named an approved vendor of Automotive Parts Associates (APA), one of the nation’s...

Read more...

Internal Engine Oil Consumption Diagnostics

Due to the variables in engine design and ­operating conditions, internal engine oil ­consumption complaints are often the most difficult to solve. In some cases, oil consumption might be more severe under low-speed operation, in other cases, high-speed...

Read more...

Hyundai Fuel System, Emissions Diagnostics

Hyundai has done a good job of improving its ­offerings over the years from both an aesthetic and mechanical viewpoint. Complemented by a strong warranty and good value, the carmaker has been able to increase its market share year over year. If you aren’t...

Read more...

Curing Volvo Manual Transmission Rattle

In an effort to increase fuel efficiency, today’s engines produce more torque so they can be ­driven at extremely low rpm. ­Reduced viscosity engine and gearbox oils, less vehicle weight and improved aerodynamics also contribute to better fuel economy....

Read more...

Servicing The Electronically Adjustable Shocks Of Full-Sized GM Trucks

Since the 2000 model year, GM has offered electronically adjustable suspension as an option on Chevy, Cadillac and GMC full-size trucks. The system actuates the valving in the shocks to control ­suspension position and body attitude. The electronic...

Read more...

Diagnosing Clutch Assembly Noises

Noise can resonate from many areas of a ­vehicle’s driveline. There are several types of noises associated with the clutch assembly. The release bearing is most often blamed for being the cause of noise when, in many cases, it is not the release...

Read more...

Making Sense Of Steering Angle Sensor Input And Data

Measuring the­ ­position angle, rate of turn and force of the steering wheel is critical for Electronic Stability Control (ESC) systems. Scan tools call these Steering Angle Sensors (SAS) and typically display the information in degrees. The SAS...

Read more...

Talk To All Available Modules With Autel's MaxiDiag Elite MD802

Derived from Autel’s Professional Series tool, the MaxiDAS DS708, the MaxiDiag Elite MD802 enables the user to not only get into the OE enhanced OBD II system with mode 6 access and live data graphing, but it also allows a technician to scan the...

Read more...

Reflashing & Reprogramming Tools

In the first half of 2014, NHTSA has issued more than 15 recalls where the fix was to reflash a module on a vehicle. In the same time frame, more than 100 TSBs have also been issued where the solution is to reflash a module. These recalls and TSBs...

Read more...

Pulling Codes: An Advanced Misfire Story The Story of P0301

This article will document code P0301 — Misfire Activity on Cylinder No. 1 — a code many of you have run into, but sometimes we have case studies that are worthy of mention. Our subject vehicle is a 2007 Mercury Mountaineer. The vehicle has...

Read more...

Home News Ford Timing Belts & Chains

Print Print Email Email

Timing belt and chain replacement is one service that isn’t going away any time soon. Most Ford engines with overhead cam timing belts have a recommended replacement interval of 60,000 miles to 120,000 miles depending on the application (see the chart on page 54). So if a customer is driving a vehicle that is more than 5 or 6 years old, he may be driving on borrowed time if the timing belt has not been replaced. The risk of belt failure goes up sharply once a belt surpasses its recommended replacement interval, which for most Ford applications (except the Taurus SHO) is 60,000 miles. The recommended replacement interval for the timing belt in the 3.0L and 3.2L V6 Taurus SHO is 100,000 miles and 120,000 miles for Focus.

The consequences of a timing belt failure on a Ford depend on the application. Fortunately for many Ford owners, there is enough clearance between the valves and the pistons so no harm will come to the engine if the belt snaps. But on older Escorts (up to 1985) with 1.6L engines as well as 1989 and up Probes with 2.0L or 2.2L four cylinder engines, a timing belt failure will usually bend a bunch of valves. The same goes for the Mazda-built 3.0L V6 in the Mercury Villager. On the older cars, the cost to repair the damage may be more than the vehicle is worth – which means your customer has to make a painful decision either way.

The main thing to keep in mind about timing belts is that belt failures often happen with no warning whatsoever. As a belt ages, the reinforcing cords that hold the belt together weaken. The belt may still look good as new on the outside but inside the cords have lost tensile strength and may be on the verge of failure.

There is usually no noise or other symptoms to warn a motorist that their timing belt has reached the end of the road. One minute the engine is running fine and the next it is deader than a dodo bird. The only sound they hear is the frustrating wheezes from an engine that cranks but won’t start because it has no compression. If the car is a Probe or an older Escort with an interference engine, the engine won’t even crank because the valves will be smack up against the pistons.

The rest of Ford’s powerplants rely on timing chains to keep the camshaft and valves moving. This includes everything from the older 289/302/351 pushrod V8s to the latest OHC 4.6L and 5.4L V8s. Chains are longer lived than most timing belts, and there are no recommended chain replacement intervals published by Ford for these engines. Even so, timing chains do stretch with age and may cause noise, retarded valve timing and/or ignition timing. Timing chain noise can also be caused by other problems as well.

CROWN VIC TIMING CHAIN NOISE

A case in point is grinding noise coming from the timing chain cover area in 2000 to 2003 Ford Crown Victoria and Mercury Grand Marquis with the 4.6L V8. According to Ford Technical Service Bulletin 03-15-7, excessive wear in the timing chain tensioner arms can cause a noisy condition. The tension arm has an aluminum base with a nylon surface. So if you find nylon and/or aluminum particles in the engine oil, it probably means the tensioner, tensioner arms, timing chains and gear set all need to be replaced.

The Ford part numbers for the 2000 model year tensioners are F6AZ-6L266-DA (RH) and F6AZ-6L266-CA (LH). For the 2001 to 2003 model years, the tensioner part numbers are 1L3Z-6L266-AA (RH) and XL1Z-6L266-AA (LH). The tension arms are 1L2Z-6L253-AA (RH) 1L2Z-6L253-AA (LH).

Ford also recommends changing the oil and filter to flush any nylon and aluminum particles from the crankcase. If the timing chain has worn through the tensioner arm into the tensioner piston, remove the oil pan from the engine and clean the debris from the oil pickup tube.

FORD CONTOUR TIMING CHAIN CLATTER

Ford TSB 97-2-8 describes a clattering noise at engine start-up after the engine has sit overnight that may be heard on 1995 Ford Contour and Mercury Mystique models with a DOHC 2.5L V6. Oil leaking out of the chain tensioners causes the timing chain to momentarily rub against the tensioner ratchet when the engine is first started. The noise only lasts a couple of seconds and goes away as soon as the engine builds up oil pressure.

The cure, says Ford, is to replace the original chain tensioner components with redesigned parts. These include two timing chain tensioners F5RZ-6L266-CA, the left hand tensioner adapter F5RZ-6C275-BA, the right hand tensioner adapter F5RZ-6C275-AA, the left hand chain tensioner arm F6RZ-6L253-AA and the right hand chain tensioner arm F6RZ-6L253-BA. The two DOHC timing chains and guide assemblies should also be replaced at the same time.

TIMING CHAIN TIPS

When replacing a timing chain on any Ford engine, always replace the chain, camshaft and crankshaft sprockets. Don’t reuse the old sprockets to save time or money. All three components wear as a system and should be replaced as a matched three-piece set. Some OHC kits also include chain guides and/or tensioners. These “extra” parts play a vital role in supporting the chain and keeping it tight and should also be replaced at the same time.

TIMING BELT REPLACEMENT

Labor times for replacing Ford timing belts obviously vary depending on the application, but typically run about two hours for the easier ones, and up to three or more hours on the more challenging applications. Should you ever encounter a 1984-86 Ford Escort or Tempo with a 2.0L diesel engine (which are very scarce, fortunately), be warned that step one of the timing belt replacement procedure is to remove the engine from the vehicle! It’s a six-hour job to change a timing belt on one of these little beasts!

On Ford Probe with a 2.0L or 2.2L four-cylinder engine, the job will probably take you three to four hours. The biggest obstacle to replacing the timing belt is the right hand (passenger side) motor mount. There is almost no accessibility to a couple of the bolts that attach the mount to engine.

Though Ford hasn’t made the Probe for several years, there are still a lot of them on the road and many have well over 100,000 miles on the original timing belt. The four-cylinder engines are interference engines so it’s important to change the belt before it fails. So here is the basic procedure for doing just that on a Probe:

  1. Remove the right front wheel.
  2. Remove the inner fender panel.
  3. Remove the accessory drive belts from the engine.
  4. Support the engine and remove the right motor mount. The two bolts that hold the mount to the engine are recessed in the mount and there is almost no clearance between the mount and inner frame rail. Raising the engine up slightly helps but you’ll need a very short socket and plenty of leverage. Good luck!
  5. Remove the six crankshaft pulley bolts and pulley.
  6. Remove the upper and lower timing belt covers.
  7. Rotate the crankshaft so the No. 1 piston is at TDC with the timing marks aligned.
  8. Make sure the No. 1 timing mark on the camshaft sprocket is aligned with mark on the cylinder head.
  9. Loosen the belt tensioner bolt, push the tensioner away from the belt, temporarily retighten the tensioner bolt to hold it in place, then remove the timing belt.
  10. It is a good idea to inspect and/or replace the water pump before installing the new belt. Why? Because the service life of the water pump shaft seals and bearings are about the same as the belt. Some water pumps will go 100,000 miles or more without a drip. Others may start to leak at 60,000 miles or less. Replacing the water pump now can save your customer the labor cost of having to replace the pump later should it start to leak.
  11. Replacing the belt tensioner and idler pulleys with new ones is also a good idea, especially if the engine has over 100,000 miles on the original pulleys. If the tensioner and/or idler pulley bearings are loose or making noise, these parts must be replaced.

  12. Position the new timing belt on the pulleys, make sure all the timing marks are aligned and that the belt is taut between the two sprockets on the non-tensioned side.
  13. Loosen the tensioner bolt so the spring will pull it tight against the belt. Tighten the tensioner bolt to 27-38 lb.-ft. (37-52 Nm) and check to see that there is about 0.3″ (7 to 8 mm) of belt deflection between the crankshaft pulley and the tensioner. You don’t want the belt to be too loose otherwise it might jump timing, and you don’t want it too tight otherwise it may overload the water pump bearings and shorten the life of the pump.
  14. Rotate the crankshaft two complete revolutions to make sure the timing marks realign properly.
  15. Reassemble everything in reverse order, and make sure you install the crankshaft sprocket baffle with the curved outer lip facing outward (if it faces inward it will rub against the belt).
  16. Lastly, install a sticker on the timing cover indicating the date and mileage the belt was replaced. This will help the next technician or vehicle owner determine if the belt has ever been replaced, and if so when it was replaced.

TIMING BELT TENSIONERS & IDLER PULLEYS

Tensioner and idler pulley bearings are “sealed for life” and are not serviceable. So there’s no way to clean, inspect or relubricate the bearings when you change the timing belt. Over time, the grease inside the bearings breaks down and oxidizes, accelerating bearing wear and increasing the risk of a bearing failure or seizure. And the hotter the operating environment, the shorter the lifespan of the grease and the bearings. The location of the tensioner and idler pulley under the timing belt cover prevents them from receiving much cooling, so they tend to run quite hot.

When a tensioner or idler bearing seal fails, dirt and humidity enter the bearing and grease leaks out. The bearing is doomed and will eventually fail. The first symptom is usually noise. If ignored long enough, the next symptom may be jumped timing as the belt loses tension, or belt failure.

If a new tensioner and idler pulley are not included with a timing belt kit, you should order them separately.

TIMING BELT SERVICE TIPS

Any belt that shows obvious damage such as frayed or exposed cords, damaged teeth, hunks of rubber missing, deep cracks, excessive surface cracking or severe glazing should be replaced – without delay! Small surface cracks on the ribbing is considered normal. But extensive cracking or deep cracks are not.

If you find a belt with stripped cogs, it would tell you something in the cam drive system has jammed or stuck, overloading the belt and causing it to shear teeth or jump time. The most likely culprit is the camshaft, which may have seized due to engine overheating or lack of lubrication (low oil level or loss of oil pressure). Check the coolant level, oil level and maintenance records of the vehicle.

When OHC cylinder heads get too hot, they usually swell up in the middle causing the cam to bend or bind. In some cases, this may break the cam, snap the timing belt or shear the cam drive sprocket off the end of the cam.

Make sure the replacement belt is identical to the original. Belt length, width, tooth profile and pitch must be the same, and the material must be the same or better. Do not substitute a less expensive neoprene belt for one made of HSN (Highly Saturated Nitrile). Use a quality brand of belt because some no-name brands use inferior materials that won’t last as long as the OEM belt or a quality aftermarket belt.

When changing a belt, never attempt to “stretch” a belt over a pulley. Belts, remember, do not stretch and forcing one to do so will likely damage the cords and cause it to fail.

Also, never pound on a sprocket to force it into place. If it isn’t sliding into place, check alignment and fit.

Misalignment problems in the cam drive can also occur if the cam sprocket is installed backwards, the wrong thickness of washer is used (incorrect end play), a thrust button is forgotten or the crank sprocket is not positioned properly on its keyway.

Belt tension is critical to belt longevity. Adjust to the recommended specifications (always refer to the manual because the amount of recommended play can vary depending on the application). If the belt is too tight, it won’t last. If the belt too loose, it may jump time.

Belt replacement is recommended any time the cylinder head has to come off of the engine, or when replacing a water pump that is driven off the timing belt. In both cases, the belt has to be removed anyway to make the other repairs so there’s no extra labor required to change the belt – and it will save your customer the cost of having the belt replaced later on.

REVISED TIMING BELT & TENSION SETUP ON 2.0L

Shop manuals are indispensable tools for looking up disassembly/ installation procedures, specifications, diagnostic and service information. But sometimes errors occur in printed manuals, which makes life interesting for the poor guy who doesn’t know the manual is incorrect. An example here is the timing belt and tensioner setup procedure that Ford originally published for the 1998-2000 Contour, Escort ZX2, 2000 Focus, 1998-2000 Mercury Mystique and 1999-2000 Mercury Cougar with 2.0L engine. Ford TSB 99-25-4 provides the following corrected information:

To achieve proper timing belt tension on this engine, Ford says the camshaft sprocket bolts should be loosened enough to permit the sprockets to turn freely on the camshafts. Once this has been done, rotate the crankshaft clockwise so cylinder No. 1 is at top dead center. Then, install the camshaft alignment tool in the camshaft slots to hold the cams in place.

  1. Back out the tensioner bolt four full turns and position the tensioner so the locating tab is at approximately the 4 o’clock position. Line up the hex key slot in the tensioner-adjusting washer with the pointer that is located behind the pulley.
  2. Working counterclockwise from the crank sprocket, install the timing belt.
  3. Rotate the tensioner locating tab counterclockwise and insert the locating tab into the slot in the rear timing cover.
  4. Position the hex key slot in the tensioner-adjusting washer to the 4 o’clock position.
  5. p>

  6. Tighten the attaching bolt enough to seat the tensioner firmly against the rear timing cover, but still allow the tensioner adjusting washer to be rotated using a 6 mm hex key.
  7. Using the hex key, rotate the adjusting washer counterclockwise until the notch in the pointer is centered over the index line on the locating tab. (The pointer will move in a clockwise direction during adjustment).
  8. While holding the adjusting washer in position, torque the attaching bolt to 18 lb-ft (25 N.m).
  9. Note: If the pointer does not remain centered over the index line during final tightening, loosen the bolt and repeat the procedure beginning with step 4.

FORD OHC TIMING BELT REPLACEMENT RECOMMENDATIONS

  • 1.3L Aspire – 60,000 miles
  • 1.6L*, 1.8L, 1.9L Escort – 60,000 miles
  • 2.0L diesel (1984-’87) – 60,000 miles
  • 2.0L SOHC Escort & Tracer (1999) – 120,000 miles
  • 2.0L SOHC Focus (2000 & up) – 120,000 miles
  • 2.0L Contour – 60,000 miles
  • 2.0L* Probe (1989-’97)- 60,000 miles
  • 2.0L* DOHC (1999 & up all models) – 120,000 miles
  • 2.0L 4-cyl Ranger pickup – 60,000 miles
  • 2.2L* Probe – 60,000 miles
  • 2.3L 4-cyl Ranger pickup – 60,000 miles
  • 2.3L Mustang & T-Bird – 60,000 miles
  • 2.5L 4-cyl Ranger pickup – 60,000 miles
  • 2.5L V6 Probe – 60,000 miles
  • 3.0L* V6 Mercury Villager (1993) – 60,000 miles
  • 3.0L* V6 Mercury Villager (1994-2000) – 105,000 miles
  • 3.0L V6 Taurus – 100,000 miles
  • 3.2L V6 Taurus SHO – 100,000 miles

(*) – Indicates an interference engine that will suffer valve damage if the timing belt fails.

The following two tabs change content below.

Larry Carley

Larry Carley has more than 30 years of experience in the automotive aftermarket, including experience as an ASE-certified technician, and has won numerous awards for his articles. He has written 12 automotive-related books and developed automotive training software, available at www.carleysoftware.com.
Advertisement
Advertisement
Advertisement
Advertisement
Latest articles from our other sites:

Beck/Arnley Launches TRUE|Friction Brake Pad Series

Beck/Arnley has launched a new brake pad series that using the same type of material recommended by the vehicle’s manufacturer. TRUE|Friction pads are specifically designed to match the most current...More

TRW's Premium Chassis Program Tops 3,000 Mark

TRW’s North American (NA) Aftermarket Group has extended its all makes premium chassis program by an addition 527 SKUs. The total number of SKUs available from TRW now exceeds 3,000. Mark Thorpe,...More

Internal Engine Oil Consumption Diagnostics

Due to the variables in engine design and ­operating conditions, internal engine oil ­consumption complaints are often the most difficult to solve. In some cases, oil consumption might be more severe...More

Hyundai Fuel System, Emissions Diagnostics

Hyundai has done a good job of improving its ­offerings over the years from both an aesthetic and mechanical viewpoint. Complemented by a strong warranty and good value, the carmaker has been able to...More

Avoid The 'Warped Rotors' Trap, Find True Pulsation Cause

The expression “warped rotors” still seems prevalent in the brake service community. According to common lore, a warped rotor is the usual cause for pedal pulsation or vibration in the car or steering...More

Getting An Accurate Toyota Tire Pressure

Ambient temperature changes can dramatically alter tire pressure, which could cause a tire pressure monitoring system (TPMS) warning light to illuminate. The TPMS must be initialized based on the tire’s...More

Ernst Offers Socket Boss Universal Twist Lock Socket Tray

Versatility is a must for organizing any socket set. Capitalize on maximum configuration possibilities with the new Universal Twist-Lock Socket Tray from Ernst. Individual rails can be removed or switched...More

Ranger Introduces New Automatic Leverless Tire Changer

Ranger Products, a division of BendPak Inc., is bringing another new tire changer to market. Its latest R80DTXF tire changer features an automatic bead lifter, variable speed turntable and bilateral bead...More