The timing belt is one of the most critical components of your car's engine, and it must be inspected regularly for signs of wear or potential replacement. The importance of the timing belt lies in its ability to keep the crankshaft and camshaft synchronised, ensuring that the engine's combustion process occurs at precisely the right moment. By keeping these components 'in-time,' the timing belt ensures that fuel and air enter the cylinders just as the pistons are in the correct position for ignition. If the timing is off, the engine may lose power or stop running smoothly. To better understand its function, let's take a closer look at the timing belt's purpose and its role within the engine.
SBT supply professional and honest service.
Depending on the age and model of your vehicle, the timing mechanism may either be a belt or a chain. Older cars, as well as some newer V-8 engines, are equipped with a timing chain. The chain is typically located at the front of the engine, housed within a protective cover. To inspect the timing chain, the cover, cooling fan, and sometimes even the radiator needs to be removed, making it less accessible than a timing belt.
Like a timing belt, the chain helps keep the crankshaft and camshaft synchronised. However, the key difference is that the chain is made of metal, which makes it more durable but also more susceptible to causing internal damage if it breaks. A snapped timing chain can result in significant damage to engine components, leaving you stranded and facing costly repairs.
In contrast, most modern cars, particularly those with smaller engines, are equipped with a rubber timing belt. The timing belt is often located just below or beside the accessory belt, and it may be behind a protective cover. This belt operates in much the same way as a timing chain, maintaining the alignment of the crankshaft and camshaft, but it is generally easier to inspect and replace during regular servicing. By having the belt inspected regularly, you can avoid sudden failures and keep your car running smoothly.
The timing of the engine is crucial for efficient operation. When the crankshaft and camshaft are synchronised, the engine's pistons are in the correct position when the spark plugs ignite the fuel and air mixture. This precise timing ensures that the engine produces maximum power and operates efficiently. If the timing belt or chain slips or breaks, the engine will fall out of time, leading to a range of issues such as:
Timing belts are usually made from reinforced rubber, but like all rubber components, they wear out over time. Most manufacturers recommend replacing the timing belt every 100,000 to 150,000 kilometres, but this can vary depending on your vehicle's make and model. During regular servicing, your mechanic will check the condition of the timing belt for signs of wear, cracks, or fraying.
Replacing the timing belt involves aligning the crankshaft and camshaft to ensure they are synchronised. Many modern cars are equipped with computer-controlled systems that help maintain this alignment, but when the belt is replaced, it's essential to align the painted dots on both the crankshaft and camshaft properly. If the alignment is off, the engine may not start or run properly, causing rough idling or poor performance.
In older vehicles, the process of replacing a timing belt or chain can be more manual. Mechanics must adjust the rotor in the distributor to ensure the engine's timing is correct. Once aligned, the car will run smoothly, but improper installation can lead to immediate issues.
While timing belts require periodic replacement, timing chains are typically designed to last the lifetime of the vehicle. However, they are not immune to wear. A worn timing chain may begin to rattle or make noise, signalling the need for inspection or replacement. Because timing chains are more durable, they can often last longer without maintenance, but the consequences of a failed chain are far more severe than a broken timing belt.
It's important to stay alert for signs that your timing belt is wearing out. Some common indicators include:
The timing belt plays a vital role in your car's engine, ensuring that the crankshaft and camshaft remain synchronised, and that the combustion process happens smoothly. Regular inspection and timely replacement of the timing belt can prevent sudden breakdowns and costly engine damage. Whether your car uses a timing belt or chain, staying aware of its condition and addressing any signs of wear will help keep your engine running smoothly for years to come.
I always hear about the disadvantages of a timing belt and how it is a $300 job every few years or so, depending on miles driven. Other disadvantages include you being stranded with a non-running engine until the belt is replaced or the worst case of an essentially trashed engine from the valves crashing into the pistons or vice versa.
Are there any real advantages to these compared to timing gears or chains? Are they better for fuel economy due to a lighter mass or is there any other practical reason for them besides getting you into the shop for a replacement or worst case a new car if you neglect them?
Conor
Not In My Opinion, Not To The Car's Owner, Although Some Will Be Offered Here, I'm Sure.
I quit buying cars with timing belts several years ago, right after I wrestled my last one into my 3.5L Intrepid V-6, out in the driveway over a couple of days, purchased and home-made special tools and all.
They're silly, really.
CSA
This topic has been beaten to death, and the consensus is that if there is an advantage, it really isn't worth it.
Want more information on Automotive Timing Belts? Feel free to contact us.
Please see http://community.cartalk.com/search?cx=partner-pub-%3A2yk2yg-lkla&cof=FORID%3A11&ie=ISO--1&q=timing+belt+advantage&sa=Search
I think I am the only person to make a case for the advantages of a belt, and even I realize calling these items 'advantages' is a stretch. In the end, the only real advantage is that replacing your water pump at the same time as the timing belt means your water pump will never get a chance to fail, and if you're lucky, your mechanic might find and repair other items that might otherwise fail or cost you more money as a separate job, like a leaky gasket or seal inside the timing belt housing.
BTW, if you can really find someone who will do a full timing belt job for $300 (with the whole kit, not just replacing the belt), take advantage of that opportunity and thank your lucky stars. On many vehicles, timing belt jobs range from $450 (on my Civic) to $900 (on some minivans). You really should get the whole kit, which includes the tensioner pulley and sometimes other important items, depending on the model.
I see. I have heard timing belts slapping covers before as well as chains on the early 's Dodge 3.9L V6 engine commonly used in the Dakota. Those Dodge engines all clack loudly at idle and I was driving a friends to get some parts at AutoZone. The AutoZone manager told me that I had a knock like a wrist pin or rod. I told them that they all sound like this and I don't recall many of these engines catastrophically failing. That can't be said for other Dodge engines such as the 2.7L used in Intrepids and similar. I am not a huge MOPAR person overall.
I got home and looked it up. There is some defect where the chains on the 3.9L slap against the inside of the timing cover and clack at idle/no load. They solved in the later '90's and you can refit the older trucks with a timing set from the newer models if you like but most people just drive them.
Anyway, I am all for the chains myself as they seem to last the life of the vehicle. I was curious if the lower rotating mass of a belt might have increased response or mileage.
Conor
I've heard people say they're quieter, but never the manufacturers. Usually it's someone offering an explanation for why they're used.
Bottom line; they're cheaper. Fortunately, I think customer dissatisfaction has led to manufacturers not using them as frequently. It seems that everything new has chains.
Cwatkin, your comment about the greater mass is insightful. It's true that lower mass needs less fuel to get moving, and since engines accelerate often in normal driving that would make sense.
Its purely cost. When they were first used, new car buyers kept their cars about 3-4 years and the belt would last 4 years, so belt replacement was not a concern to the new car buyer. The manufacturer doesn't make any money off the second owner so they are not concerned.
A first owners started keeping their cars longer, the manufacturers began increasing the life span of the belts through better materials. As long as the initial purchaser traded the car before the belt change was due, it was not a concern for the manufacturer.
It finally became a concern for the manufacturers when their customers began to hold onto the car for 10 years. Belts can be made to last that long by using more composite materials and silicone rubber, but it appears that it is cheaper to use a chain rather than upgrade the belt materials.
I have heard the 'quieter' argument in relation to timing gears. My parents had a Pontiac LeMans V-8 that had nylon timing gears. The timing gears failed and steel replacemetn gears were installed. I couldn't hear any difference in the engine sound. The Chevrolet my dad owned had some kind of fiber composition for the timing gears. Again, the argument was that these fiber composition timing gears were quieter. Chevrolets of this vintage with the 'Stovebolt' 6 engines were known to have timing gear failure. Fortunately, these engines were not interference engines. The tappets in these old Chevrolet engines were often so noisy that any noise of the timing gears was drowned out anyway. r
Both the Toyota 4Runner V-6 we own and the Toyata Sienna V-6 we own have timing chains and I haven't been bothered by noise from this set up.
I recently got a Geo Metro 1.0L 3cyl for gas mileage and it has a timing belt. The job on this takes like 1-2 hours to do by myself. That is a $35 kit with Gates belt, new timing seals, a tensioner/idler, etc. I went ahead and replaced the water pump which was also $35 at the same time.
Now these little cars are essentially the modern day VW bug if you can consider something 20-30 years old 'modern' and are super easy to work on. Everyone says, 'I bet that is a pain to work on with lots of small/tight spaces.' It is actually like working on an old pickup under the hood as it is easy to do just about anything. I can change an entire engine by myself in like 4 hours without a hoist. All I need is a car jack and a metric socket set!
Conor
A timing belt has its drawbacks but also some great benefits. A V engine with overhead cams, especially dual overhead cams, is much cheaper to manufacture but it is also much cheaper and simpler to repair than the chain drive model. Ford Windsor V 8s were notorious for tossing chains at 80,000 miles with manual transmission and 120,000 with automatics and even that simple, non interference engine required longer to replace the chain than a Hyundai, Mazda, Toyota or Nissan V-6 T-belt. And a Mazda 929 was an easy 2 hour job.
And let a Toyota R-22 chain slip while the head is off. That slip will cost you dearly. And BTW, check the flat rate time to replace the timing chains on a Jaguar 4.2L or Mercedes V-8.
For more Audi Timing Belt Replacementinformation, please contact us. We will provide professional answers.