Timing belt replacement

 

The right time to timing belt replacement

Timing Belt Replacement

Timing belts are considered wear items and should be checked according to the manufacturer’s recommended service schedule. Most manufacturers suggest replacing the belt between 60.000 to 90.000 miles. Check your owner's manual to determine timing belt replacement schedule for your particular model. Otherwise, without any prior alert about the upcoming failure, the costs of repair may be thousands of dollars. In case of some older cars the repair may turn out to be completely uneconomical in such a scenario. A complete engine overhaul virtually means the death of the car. The older the vehicle, the more often timing belts should be replaced. Occasionally, timing chains may last for the whole lifetime of the car, but this depends on a specific model. Some chains need replacing along with the sprockets after several hundred thousand miles. Rollers and tensioners require more frequent replacement.

 

 

Timing belt replacement is not the end. There are other components interacting parts:
- timing belt rollers,
- camshaft and crankshaft seals,
- tensioner

If the water pump is driven by the timing belt, it should be checked as well. It will often need need replacing, too.

It is also important that the car mechanic carefully checks for oil leaks from the engine, especially in older cards, where the oil often tends to leak out. If the shafts are not properly sealed at this point, the timing belt will wear out quicker.

This is why car mechanics emphasize the need for replacing the timing belt after the purchase of a used vehicle, unless you get a service book from the previous owner with the date of the last replacement and, more importantly, the mileage at that time. The seller might also produce the invoice for the replacement instead of the service book.

The lifetime of the timing belt depends on many factors. The most important ones include the style of driving and exploitation conditions. Frequent acceleration and braking when driving in city traffic results in increased tensions and promotes quicker wear of the belt. What’s more , when you’re stuck  in a traffic jam, the engine keeps running even though the mileage does not increase. Besides, the timing belt will naturally age over time, so even if the mileage is low, it should be replaced every three to five years at the latest.

Admittedly, the mechanic could say the belt is in a good condition. But the problem is that even a nice looking belt might be so worn out that it will break just after you drive out of the repair shop. No repair man could possibly guarantee otherwise by visual inspection alone.
Never save on good mechanics. The timing belt replacement will be crucial for the life span of your engine and the long-term costs of using the car, so leave this task to someone experienced. Remember that it takes not only a general repair experience, but also an acquaintance with your car’s specific make. Otherwise, the repairman might be unable to properly assess the condition of all the engine components cooperating with the timing belt. Many of them are replaced based on the mechanic’s intuition rather than specific recommendations of the manufacturer.

Never save on parts, either. With the timing drive system, be extremely careful about cheap substitutes. It doesn’t really makes sense to save a couple of hundreds dollars if you’re going to spend thousands in case of a serious failure.

A failure of the timing belt gives almost no symptoms in most cases, unless there has been some damage to the water pump or one of the rollers: then you will notice the wooing or roaring sound. If the engine suddenly stops and starts making some strange sounds, it is always the best solution to stop it and call a car breakdown recovery service or tow the car to a repair shop. If the engine has stopped and you suspect the timing belt might have been broken, don’t try to start it again or the damage could become even more serious!

Keep in mind that push-starting or tow-starting your car might end up badly. If your timing drive system employs a timing belt, the valve timing could go out of sync , and in extreme cases, the timing belt might break. This in turn directly leads to a major failure and a complete engine overhaul. The risk is much lower if your engine runs on a timing chain.

Automobile engines can be classified as either Free-Running or Interference, depending on what occurs if piston/valve synchronization is lost.
As illustrated below, in the free-running engine with the crankshaft still moving, there is enough clearance between the valve and piston, even if the cam stops with a valve fully open.
However, interference engines usually sustain damage if synchronization is lost. As illustrated, disrupted synchronization allows the piston and valve to collide causing damage and very expensive repairs for the vehicle owner. Damage can occur to valves, pistons, or heads, and in some cases, completely ruin the engine. Most import (with higher compression engines) and most car and light truck diesel engines are interference. To avoid costly engine repairs, follow the auto manufacturers’ mileage replacement recommendations or we recommend timing belt replacement at around 60,000 miles.

Timing belt exchange
Since timing belts are inside the engine they tend to be an out-of-sight, out-of-mind item and are seldom thought of as a part of routine maintenance. Here are some questions to ask customers that will help sell belts and protect the customer from expensive repairs:

1. Did you buy the car new? If yes, they’ll know if the belt has ever been replaced.
2. Did you buy the car used? If so, they won’t know if the belt has been replaced. This is a flag for the customer to get the belt checked, replaced or at least be aware that he has a timing belt.
3. How many miles are on the vehicle? Generally belts should be replaced at around 60,000 miles or less.
4. Have you ever replaced the timing belt? If the answer is yes or no (and the customer knows the mileage) you can determine where the vehicle is in the replacement cycle.

Here’s a helpful hint for customers with vehicles within a few thousand miles of the recommended replacement interval. If they are having any engine repair done, have the timing belt checked. If it needs replacing, do it along with the other repairs and save time and money.

 

Automotive drive elements guarantee operating safety and optimal timing belt life provided the following advice is followed:
- The pulleys should be correctly aligned.
- Before assembly the drive centre distance is to be reduced so that the belts can be fitted without undue force.
- Subsequently the drive elements are to be tensioned in according to recommendations.
- Fan belts for drives with multiple grooves should normally be supplied in sets.
- Timing belts are to be fitted according to the car manufacturer's instructions.