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.
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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.
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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.
Are you interested in learning more about Automotive Timing Belts? Contact us today to secure an expert consultation!
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.
Timing is everything. For jokes, music, cooking, dating—even engines! That’s because your car’s engine relies on a timing belt to stay in sync. The timing belt makes sure everything in the engine is operating smoothly, keeping you safe on the road.
Replacing the timing belt is an important maintenance item! So, if you own a car, you should understand how a timing belt works and when to replace it.
Read: The Car Maintenance Checklist Every Driver Needs
Think of a timing belt like a bike chain for your vehicle—it keeps all the internal moving parts of an engine in sync. It also sometimes powers the water pump, oil pump and injection pump.
The timing belt is a rubber belt with hard teeth that interlock with the cogwheels of the crankshaft and the camshafts. It synchronizes the movement of the crankshaft and camshafts. This ensures that the engine intake and exhaust valves open and close in time with the pistons. If the crankshaft and camshafts are not operating in unison, the vehicle will not run correctly.
If the intake valves open too early, there may be too much fuel-air mixture flowing into the engine combustion chamber, leading to poor combustion and power loss. And if the exhaust valves open too early, the combustion chamber will lose pressure and cause a power loss. If the engine components are very out of sync, they might collide and damage each other, resulting in costly repairs.
Depending on your vehicle model, you might have a timing chain instead of a timing belt. A timing chain functions the same as a belt, but it is metal instead of rubber. Because they are lighter and quieter, timing belts became popular to use after they were introduced in the s.
Thanks to design improvements and a long lifespan, many modern cars have returned to using timing chains instead. If your car has a timing chain instead of a timing belt, you may be able to go longer before replacing the timing chain. As always, check your owner’s manual or give us a call to be sure.
It’s important to replace your timing belt at the mileage intervals your vehicle manufacturer recommends. Every manufacturer is different, but typically, it needs to be replaced every 60,000–100,000 miles. The recommended interval for your specific vehicle can be found in your car’s owner’s manual.
Because the timing belt is made of rubber, it will wear down over time and eventually break. When it breaks, the engine will stop running or the components will be out of sync, damaging the engine.
If you don’t replace the timing belt at the recommended time, you could end up with total engine failure, broken or bent valves, cylinder head or camshaft damage, and piston and cylinder wall damage. This is not the type of situation where it’s safe to think: ‘If it’s not broke, don’t fix it.’ Replace the timing belt according to the manufacturer’s maintenance schedule to avoid thousands of dollars repairing or replacing your engine.
Often, there aren’t any warning signs before a timing belt breaks. But here are some possible indicators that it might be time to replace your belt:
While your vehicle is in for service, we recommend also replacing the water pump. The water pump usually has a similar lifespan and is easy to access when the timing belt is off. That way you save money on labor costs.
Read: What Is a Serpentine Belt & When Should You Replace It?
Replacing the timing belt is an expensive service. It is an intricate, labor-intensive process that can take 4–8 hours, depending on the vehicle. But replacing the timing belt before it breaks will prevent engine damage and save you money in the long run. If you’re unsure about your belt needs to be replaced, stop by Virginia Tire & Auto today.
If you are looking for more details, kindly visit Audi Timing Belt Replacement.