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Timing chains vs belts

I recently bought a used Nissan Versa from Hertz (THE way to buy a late model used car IMHO) and, perusing the maintenance schedule was nonplussed by the absence of any mention of a timing belt replacement. Come to find out it has a timing chain which is supposed to last as long as the car. Now, I thought that timing chains had gone the way of the do do and it has me wondering why they are not in all cars, saving owners the price of replacement.

Hate to let you in on a little secret,hordes of people have already posted the exact same question,use search, unless you are just “venting” which is OK.

CarTalk is a pretty loose Forum. On other more disciplined forums people get irritated when the same questions are posted over and over.

The short answer is that both timing belts and timing chains have advantages, which rely heavily on the overall design of the engine. Some benefit from the belt, and some benefit from the chain. Do a search using “timing chains” to find a long list of threads dedicated to this issue.

That Ship Just Sailed From Here A Few Weeks Ago. Click The Link And See Our Discussion.

http://community.cartalk.com/posts/list/2126095.page

CSA

Oops! Sorry!

CSA

Chains are better. Every timing belt change is another expensive opportunity for an even more expensive error.

I’ve noticed that manufacturers seem to be returning to chains for 4-bangers. Hopefully they’ll return to all engines, although in DOHC V-style engines the chain has to travel a more convaluted path, adding some complications to controlling the chain at high RPMs. Chains have much more weight, and at high RPMs they want to form a circle. But it really isn’t that big a deal design-wise, it’s more that chains are more expensive to manufacture in than are belts.

Actually I did search before posting, found lots of posts about timing belts and timing chains but not WHY some use one and others the other.

I guess in truth it’s because the department heads of some design groups are more cost-oriented and the department heads of other groups are more robustness-oriented. Belts are cheaper. Chains are more robust.

My understanding is that chains are a bit more expensive than belts and a bit noisier. Personally, I’d prefer a chain because changing a belt on a transversely mounted motor (modern FWD cars) is a PITA if you do it yourself, and expensive if you have it done. For cars with interference engines, I think belts are a fairly dumb idea – especially if the water pump is driven from the timing belt. We had a water pump seize up at 40K miles 500 miles from home on one of our cars. Broke the timing belt of course. Fortunately a non-interference engine.

As a result, I consider an interference engine with a timing belt driven water pump to be a bed enough idea that I won’t buy a car built that way.

You do know that chains are used on high rpm DOHC V-8’s and V-10’s? It sounds like you think belts are better

Generally, it’s purely a manufacturing cost issue. But manufacturers have learned that when a rubber belt breaks and destroys the engine in a customers car, that person is unlikely to buy that make of car again…Also, consumers are demanding maintenance-free cars and rubber timing belts do not fill that need…Cars with a reputation for requiring a lot of expensive maintenance will become impossible to sell.

Chains generally last a lot longer (usually life of the car) and they generally warn of impending failure by developing noise.

Belts are quieter.

I have also heard, but not confirmed, the belts can maintain tighter specs.

I do know that.
Let me reiterate and clarify: chains are better. But belts are used because they’re cheaper to manufacture.

I like chains. Accountants like belts.

While I understand the theory behind the statement that chains are noisier, and I’m familiar with it as “common knowledge”, I’ve never actually heard a chain running that didn’t need replacement. Is the “common knowledge” a holdover from days when tolerances were not what they are today? Should it be relgated to history?

Thoughts? What say you?

There are timing chain set-ups that drive the cam in your 1985 small block and then there are timing chain set-ups that drive you cams(4) all overhead in your BMW V-10 all they share is the name. You cant equate what happens to the GM quality system to the BMW system.

Read a pretty neat article about vriable valve timing from GM for their pushrod V-8’s,breathing a little life into the pushrod system.Check-out “Motor” magazine,it is time well spent to keep you at least a little current.

TSM, Send It To The Trash Bin! My Bonneville’s Engine Is As Quiet As Any Timing Belt Mill. Inside The Car, Even Going Down The Road, It’s As Peaceful And Pleasant As A Library, After It’s Closed!

Seriously though, I have both vehicles with belts and chains and the sound difference is indiscernable. In fact, the Bonneville’s engine is quieter than many timing belt engines.

CSA

Why is somebody resurrecting a 2009 posting?

Maybe that’s the last year Tom & Ray did a new show?

It was me I was searching for a question I had and wanted to put my two cents in.

I’m not much of a mechanic, obviously but I was under the impression than timing chains last longer.

I still like a timing belt for interference engines. After 250k miles timing chains have stretched enough that it may slip. A timing chain slip on a interference engine…same as if a timing belt breaks. Replacing a timing chain is as costly or more then a 3-4 timing belt replacements…plus many decent back-yard mechanics can do a timing belt in 3-4 hours on the weekend.

Personally I’d like to see timing chains and NON-INTERFERENCE engines…That would be my choice…But in either case…it’s NOT a deal breaker…I’d rather buy a car that’s reliable and suits my needs with a timing belt I have to replace every 3 years as opposed to a pos vehicle I have to put thousands of dollars in repairs every year.