Replace Your Timing Chain

February 22, 2014

What is a Timing Belt and When Should it Be Replaced?

We all do the best we can to protect our vehicles and we all make sure to keep them maintained against all possible threats and dangers. However, it should not be surprising to learn that one of the greatest dangers to high mileage cars is also one of the least well known. While we expect and try to prevent cases of engine or transmission failure, the death of many older or high mileage cars is nothing other than a failure of the timing belt. However, in order to understand what makes the timing belt so important and how we can prevent it from failing, we first need to learn a little bit about what it does and what we should expect from specific car models when it comes to life expectancy of the belt.

The timing belt serves a very important part when it comes to making your engine run. Namely, the timing belt is the belt that controls the camshafts in your engine and keeps the entire operation running smoothly. Note that timing belts are present in engines with overhead cams, and are essential to keep these cams turning at the right time in order to keep the engine running. Remember that a camshaft is the shaft that opens and loses the intake and exhaust valves in your engine, both letting air in to create combustion, and venting the exhaust that comes from those explosions. A timing belt must be properly calibrated in order to move in time with the motion of the pistons.

When it comes to engines, the two most important terms to remember when talking about timing belts are “interference” engines and “non-interference” engines. Interference engines have a very, very small amount of space between the valves and pistons, while non-interference engines tend to have a lot more room.

The different types of engines make a major difference when figuring out how bad a timing belt failure can be for your engine. In an interference engine, with little space between the valves and pistons, a slip or break in the belt can send a piston flying into an open valve. When this happens, it is similar to the engine self-destructing, as it will soon become nothing more than an unusable mess of metal. This is not to say, however, that a timing belt failure in a non-interference engine will not be damaging, as it can still cause a great deal of damage to many engine components. Generally speaking, however, a timing belt failure in a non-interference engine will not cripple the motor.

Regardless of what type of motor is present in your car, a failure in the timing belt will cause the engine to suddenly stop. This means that your car will suddenly stop running and you will not be able to get it started again. In all cases, this means calling a tow truck to come pick up your now non-running vehicle.

If all of this sounds like a nightmare, that’s because it can really urn out to be one. Luckily though, timing belt failure is somewhat easy to prevent, and although it may not be the cheapest or easiest operation in the world, it is definitely a better option that purchasing either a new car or a new engine.

Of course, checking to see when your timing belt was last changed is not always the easiest task either. If you have owned your car, and have ever had it replaced in the past, you should have the mileage written down as to when it was changed. If, though, you purchased your car used, there may be a sticker located under the hood of your car that gives the mileage of the last change. If you cannot find this sticker, than it may be better to have the belt changed, just to be on the safe side. If you have the owners manual for your vehicle, it should detail when the belt should be changed.

If you have trouble finding out when exactly the belt should be changed; you could consult either a local mechanic or contact a dealership for the exact number. A good general rule of thumb is that a timing belt should be changed every 60,000 to 75,000 miles, although some belts are designed to last up to 100,000 miles before requiring a change. Regardless though, it is best not to let a belt go more than 80,000 miles or so, even if the recommended change point is a lot higher. Changing your belt early is definitely a lot safer for your engine, and a little money out of pocket can save you a lot of money and a new car in the long run.

Remember, even though you may get your oil changed every 3,000 miles, and do all of your scheduled repair services, nothing can save you from a timing belt failure. Make sure to get your timing belt replaced regularly and by a certified mechanic. It can mean the different between a good running car and useless piece of metal.

April 27, 2012

When To Replace Your Timing Belt

Timing belt replacement is the “must-do” service operation which every car owner should know about. Along with that knowledge, we should be aware of whether our engine is considered an interference engine or not. These two bits of information can, at a minimum, save us from unexpected breakdown and in the extreme can help us avoid thousands of dollars in repairs.
Without getting too technical, the synchronization between two internal engine parts (the crank and cam shafts) is accomplished with the help of the timing belt. In the process of these two parts moving the valves open and close in close proximity to the pistons. This constitutes an interference engine, because if the timing belt jumps a tooth on the sprocket on which it rides or the belt fails altogether the valves and pistons will “interfere” with each other.

This collision will cause major damage to the engine. The repair bill will, on older vehicles, often exceed the value of the car. On the other hand, a car whose engine is not configured this way will simply lose power or will not start. While this might be more desirable than facing huge repair costs, it is something that is better avoided if possible.

The motivation for preemptive replacement of the timing belt is obvious. But how do you know when to replace it? There is always the owner’s manual which will indicate mileage of anywhere from 50,000 to 90,000 miles. For a comprehensive list of timing belt service intervals and the type of engine (interference or not) check out About.com.

Some other considerations relative to timing belt replacement are:

1) Is the vehicle leaking any type of fluid that might degrade the belt, if so disregard the suggested replacement interval and replace the belt ASAP as well as repair the leak;

2) Do you know the repair history of the vehicle if it is not verifiable err on the side of safety and replace the belt;

3) Timing belt replacement can be labor intensive. Since the water pump is usually accessed in the same operation you might consider replacing the pump at the same time even if it doesn’t leak. You will save on labor and possibly prevent a pump replacement later on that will also necessitate the belt to be replaced again;

4) To avoid subsequent failure consider replacing sprockets and tensioners that are part of the timing belt system. All components are sometimes sold as a kit and can be less expensive than purchasing them individually.

All service intervals should be followed in order to protect your investment and maintain the integrity of your warranty. In the case of the timing belt, it just makes sense.

April 24, 2012

What you will need:

1. Combination Wrenches
2. A Socket Set
3. Torque Wrench
3. A Harmonic Balancer Puller
5. A Three-jaw Gear Puller
6. Screwdrivers
7. Hammer and Punch
8. Gasket Scraper
9. Timing Light
10. Tube of Silicone Sealer
11. Timing Chain Cover Gasket Set
12. New Timing Chain and Gears
13. Drain Pan
14. Antifreeze
15. Jack
16. Jack stands

Before You Start:

Follow these instructions carefully. Read and be sure you understand them before you begin.
Gather together all of your tools and supplies before you begin.
Allow plenty of time to do the job so you don’t have to hurry.
Remember that these are general instructions. For more detailed instructions pertaining to your specific vehicle, consult an appropriate repair manual.
Safety is important whenever you’re working around machinery. Beware of hot objects, sharp instruments and hazardous materials.
Don’t substitute tools unless you’re sure you won’t compromise either your safety or the performance of your vehicle.
Never work on a vehicle that is only supported by a jack. Use jack stands to support the vehicle while you work. Work on a solid, level surface. Never jack a car up on dirt or grass.
Why Replace Your Timing Chain?

Over time, wear on internal working parts of your engine will spell the need for replacement. One of the internal working parts that wear is the timing chain and timing sprockets. The timing chain and sprockets are the connecting line between the crankshaft and the camshaft. As the crankshaft turns, via the timing chain, it drives the camshaft that operates the engine’s valves via the lifters, push rods and rocker arm assemblies The timing of the valves opening and closing at precise intervals is crucial for proper engine operation. As the timing chain and sprockets wear, this precise timing of the valves gradually changes, eventually to a point where replacement is necessary.

Telltale signs of worn out timing chains are:

Rough idle.
Sluggish performance and poor economy.
Sudden engine performance change including the inability to start the engine.
Intermittent backfire through the intake manifold.
Inconsistent ignition timing or a clattering noise coming from the front of the engine.
Before starting the disassembly procedures, I would suggest cleaning the engine with an engine degreaser. A clean engine is easier to work on and helps prevent dirt or contamination from entering the engine during disassembly.