Timing Chain vs. Timing Belt

[WyrTwister]

The timing system on my 289 has a cam gear / sprocket with plastic / nylon teeth . As a typical teenager of the time ., I had flogged it many times . The system was so worn I removed the chain before I removed the gears / sprockets . Had to go down to the parts house and purchase a puller to remove the sprocket / gear from the cam .

So much slack on the slack side of the chain , it had been rubbing on the front cover .

Buick 3.8l Timing chain , cam sprocket , tensioner $ 210.37 + freight RockAuto.com

Sonic 1.8l Timing belt , tensioner , idler $ 127.79 + freight RockAuto.com ( not including water pump which is not under the plastic covers and can be services independently

The whole timing belt system can be accessed with out going " inside " the engine .

The kit for the 66 model 289 , 2 barrel engine is $ 20.54 + freight from RockAuto.com . Reverse progress ?

Wyr
God bless


[/quote]

I had a 289 in a 1965 Mustang and it had a timing chain and the chain had a very simple path, from the crankshaft up to the
cam shaft. The engine had push rods. I rebuilt the 289 in my Mustang at age 17 and learned a lot about engines.

Today's engines with a timing chain have a much more complex path for the chain with over head cams, idlers. [/quote]

 

[MarkM66]

Originally Posted by aquariuscsm
I always thought chains were a lifetime part and belts were a maintenance item. I never once heard of timing chain failure until Ford's 5.0.


Google GM 3.6 . Cadillac, Traverse, Acadia, etc. Late 2000's especially.

 

[DerbyDave]

Originally Posted by Ifixyawata
Originally Posted by Trav
(some new ones do run in oil)



Belts in oil? Sounds like it would normally be a recipe for disaster.

I know it's not a car engine but my mower has a Honda GCV160 small engine with a timing belt that runs in oil. Considering there are probably millions of those engines out there you would think if there was a problem it would be pretty well known by now.

 

[talest]

Originally Posted by oldhp
Originally Posted by benjamming
Interference or non-interference is what you really need to know.


^^^^^This^^^^^^


In a non-interference engine, the belt can snap or come slightly loose to make a tooth or two jump and you will be okay.

 

[slacktide_bitog]

Easy, chains. They don't need to be replaced

Timing chain noise is not a problem. Any noise the chain makes is drowned out by the fuel injectors anyway

 

[exranger06]

Originally Posted by aquariuscsm
I always thought chains were a lifetime part and belts were a maintenance item. I never once heard of timing chain failure until Ford's 5.0.

Chains ARE a lifetime part and usually don't need to be replaced, like most of the parts of a car. But sometimes, stuff happens and things break unexpectedly. Some engines are known to have common timing chain issues, just like some engines are known to have head gasket issues, intake manifold issues, ignition coil issues, etc. It doesn't mean those parts aren't lifetime parts either.

I prefer chains since it's one less thing to deal with maintenance-wise. I replaced the timing belt on my Accord 2 years/12k miles ago and I'm glad I don't have to think about that again for a long while. The rest of my cars have chains. My Ranger has the 4.0 SOHC V6 which was infamous for timing chain tensioner issues, but I have a 2006 which has the updated parts from the factory and should be OK. I have 79k miles and no issues so far. Time will tell but I'm not losing sleep over it.

 

[Anduril]

Originally Posted by slacktide_bitog
Easy, chains. They don't need to be replaced

Unless you own a VQ35/40. Or a GM 3.6.

 

[supton]

I like chains, but only if they last "forever". TBH I haven't owned anything that long, 300k was the longest and I kinda doubt I'll ever do that again, so chain is probably best. Avoiding problematic versions, that is.

Originally Posted by Trav
Originally Posted by vwmaniaman
I prefer neither belt or chain. I like the old fashioned gear on gear drive bathed in oil. They never fail for the life of the motor. My old VW's are my example.


That is the best but a bit tricky with modern higher output DOHC V engines, it has been done though. Duesenberg DOHC with gears, it looks like the top 3 could be eliminated on a modern engine but the physical size of the block may pose issues.

Edit: The sound from that drive must be amazing.

 

[PandaBear]

Belt on a FWD 4 cylinder cost about $250-300 labor, last 60-90k miles usually, and you replace the accessory belt and water pump at the same time as preventive maintenance (parts are likely only $50 for belts and $80 for pump).

Chain on a FWD 4 cylinder cost about $1000 or so labor (I assume, please correct), last 150k to retirement, and you replace accessory belt and water pump when they leak.

I would prefer a chain if it is a reputable engine that doesn't have stretching or guide wear problem, but these days it is hard to know ahead of time if you are buying new.

 

[atikovi]

Originally Posted by aquariuscsm
I always thought chains were a lifetime part


50 years ago they were when most cars didn't go much over 100,000 miles. Today most people expect to get 200,000 or 300,000 miles from an engine but the chains are a wear item and can't be expected nor are they designed to go that long. Could they be designed to? Sure. Double or triple row chains to reduce wear on each chain, but don't expect any manufacturer to go that route these days.

 

[DejaVue]

Originally Posted by atikovi
Belts generally much easier than chains. In the last 2 months I've done a Honda V6 belt, VW 1.4L belt, and GM 3.6L chains. The GM takes 3 chains, a bunch of guides and tensioners and a dealer would charge over $2,000 for the job.

And that 3-chain GM setup is/was garbage with plenty of 50,000 miles fails.

A thing about chains is the chain may last but the plastic guides may break, so you wind up replacing it all anyway. Still, chains are generally lower maintenance than belts.

 

[slacktide_bitog]

Originally Posted by atikovi


50 years ago they were when most cars didn't go much over 100,000 miles. Today most people expect to get 200,000 or 300,000 miles from an engine but the chains are a wear item and can't be expected nor are they designed to go that long. Could they be designed to? Sure. Double or triple row chains to reduce wear on each chain, but don't expect any manufacturer to go that route these days.


My car has almost 300k on the original timing chain

 

[kschachn]

Originally Posted by slacktide_bitog
Originally Posted by atikovi
50 years ago they were when most cars didn't go much over 100,000 miles. Today most people expect to get 200,000 or 300,000 miles from an engine but the chains are a wear item and can't be expected nor are they designed to go that long. Could they be designed to? Sure. Double or triple row chains to reduce wear on each chain, but don't expect any manufacturer to go that route these days.
My car has almost 300k on the original timing chain

Yep, same here on my single-row 1NZ-FE.

Also my BMW @ 240K but that has two rows which must explain the longevity

 

[ARCOgraphite]

My '98 m roadster timing system was toast at 58K miles. Of course I bought it at 58K miles.

That M was the Best sports car I've driven other than a Nissan Z32 (300ZX) - and thats more of a GT.
Still struts in the bimmer = weak point. Front suspension in the Nissan is worlds better.

 

[Patman]

I'm pretty happy knowing my Civic's R18 engine has a timing chain instead of a belt, and I have not heard of any issues with the chain on these engines even on those with very high mileage.

 

[DGXR]

Timing chains are designed to last the life of the engine. People talking about changing timing chains... that is only necessary in very high mileage engines, when a failure occurs (rare), or when a design flaw makes the chain or guide(s) wear out prematurely. So I would choose a timing chain over a belt all day long... just choose a make/model with a reputation for quality (not a Chevy HHR lol), find an example in good condition, then take care of it... stay on top of the service intervals and don't abuse it. Never had a timing set problem and never had to replace a belt.
It's interesting to note that some manufacturers started out with timing chains, then switched to belts when they became popular, and then went back to chains after numerous issues. Belts don't fail often, but by what I have seen, it happens much more often than a timing chain failure. An interference engine with a timing belt is just a disaster waiting to happen, not sure if this combo was ever produced but I sure hope not.

 

[exranger06]

Originally Posted by DGXR
Timing chains are designed to last the life of the engine. People talking about changing timing chains... that is only necessary in very high mileage engines, when a failure occurs (rare), or when a design flaw makes the chain or guide(s) wear out prematurely. So I would choose a timing chain over a belt all day long... just choose a make/model with a reputation for quality (not a Chevy HHR lol), find an example in good condition, then take care of it... stay on top of the service intervals and don't abuse it. Never had a timing set problem and never had to replace a belt.
It's interesting to note that some manufacturers started out with timing chains, then switched to belts when they became popular, and then went back to chains after numerous issues. Belts don't fail often, but by what I have seen, it happens much more often than a timing chain failure. An interference engine with a timing belt is just a disaster waiting to happen, not sure if this combo was ever produced but I sure hope not.

Belts USUALLY only fail when the owner neglects to change it at the manufacturer recommended interval. A typical interval is every 90k miles or every 7 years, whichever comes first. The problem is, many non-car-savvy people don't even know what a timing belt is or that you're supposed to change it every so often. So they have a belt that's 10+ years old and has 150k+ miles on it, and one day, it snaps without any warning. You're supposed to change them LONG before that happens, while the engine is still running fine. And yes, interference engines with timing belts are VERY common. Many engines have suffered valve damage from people who didn't change their belts on time. As long as you change the belt AND replace the other wear items driven by the belt (tensioner and idler pulleys, water pump) according to the recommended interval, you shouldn't have anything to worry about.

 

[zzyzzx]

Originally Posted by WyrTwister
Only timing chain I have ever done was in the 70's on a 66 Mercury Comet 289 , 2 barrel manual .

We purchased a new 2015 Chevy Sonic 1.8l automatic , June 2015 . It has a belt .

At first , I was miffed . The more I read , it seems replacing a timing belt is probably easier and possably cheaper than an equivelent timing chain ? What say yea ?


I think on that particular engine it's supposed to be relatively easy to change the timing belt yes.

 

[Eddie]

I preferred T belt when I could do the work to change the belt but, when I got too old to do belts, I prefer a chain. You ask why? Because dealers seem to love high dollar maintenance jobs. Ed

 

[Trav]

That can be true, gravy work that pays good book. The first time I ran into a timing belt was on a 67 Pontiac Lemans 6 cyl SOHC, even back then they lasted a long time and were easy to do