Timing Belts?

[Pathfinder76]

How often do they really go?

Most guys I know never have them changed. Growing up my dad had a Nissan truck he put near a million KM's on and a Pathfinder with over 600k. Lots of guys I know with 350k on vehicles with no change. Of course it is recommended, but someone is making a buck off of it. Thoughts?

[omega50]

My buddy buys and flips certain SUV's that have had timing belt failure. Repairs or drops in a motor and flips for good money. Often with less than 150K km. Generally buys otherwise great condition vehicles for under a grand. They are everywhere.
Generally very high mileage vehicles are chain driven

[fishtank]

Just change it at the recommended mileage ...for a piece of mind . It's going to cost you a lot more then that ,when it goes while you are driving on a highway. Or middle of nowhere .

[CaberTosser]

Depending on the engine it can be a real annoyance if you forego the preventive maintenance and the belt breaks. In my case I've had it happen twice, but not from negligence on the maintenance end (once from well-intentioned incompetence though!). In most VW 16V & 20V engines made for the past couple of decades the engines are what is referred to as a 'contact engine', the definition being that the pistons and valves have some overlap in regards to real estate that they occupy. When a timing belt breaks on a contact engine then the valves contact the pistons and invariably something has to give, typically its a row of bent valve stems and the resulting total loss of compression/ engine function. I presently have a Passat Wagon that I have to replace the cylinder head on, I bought the car used and had the misfortune for the timing belt to break before I had even gone through the second tank of fuel . I had been planning the maintenance job and even accumulating parts already based on not knowing the cars maintenance history but fate had other plans for me.... Otherwise the car is in great shape but I need to accomplish some other priorities before tackling that job.

On another previous VW I had changed the timing belt but it was the first time I had done so. Apparently tightening the belt tensioner until you can just turn the belt 90 degrees is a bad rule of thumb, mine was overtightened and snapped. On the other hand I got to do a pretty sweet port job on the head and port-matched all of the manifolds as well.

[blacknorthernjk]

If it's a non interference fit engine and the belt breaks...which yes they do... it's likely to be just an inconvenience for you until repaired. But if it's a cheap interference design engine you're likely to have catastrophic engine failure. Hyundais were the worst for that for a while, 4 years or 80k kms almost like clock work. And often it's just the teeth that sheer off the belt

[ESOXangler]

Originally Posted by blacknorthernjk

If it's a non interference fit engine and the belt breaks...which yes they do... it's likely to be just an inconvenience for you until repaired. But if it's a cheap interference design engine you're likely to have catastrophic engine failure. Hyundais were the worst for that for a while, 4 years or 80k kms almost like clock work. And often it's just the teeth that sheer off the belt

Yup exactly! If she's an interference follow the rules. I changed my Subaru at 90k when I bought it and it showed a lot of cracking and wear! Learn to do it yourself. Subarus aren't that complicated IMO.

[saskbooknut]

Subaru Forester has had a timing chain since 2011.
My previous vehicle, a Nissan X-trail also had a timing chain rather than a belt.
Just plain intelligent design, as is a non-interference engine.

[artie]

I have looked at a few pistons that have had valves driven into them when the belt breaks. I always thought it was the manufactures cheaping out by putting on timing belts and not chains.

[elkhunter11]

A hunting partner had a Mazda that he used to commute about 1000km/week.Ower more than 700,000km he changed the belt several times. To start with he changed the belt as recommended, but after a few years, he decided to run it until it failed, to see how far it would go. He found that the belt would fail at around 115,000 to 120,000km if run to failure.

[JB_AOL]

Originally Posted by saskbooknut

Subaru Forester has had a timing chain since 2011.

interesting.. (I own a 2014 forester and didn't know that.) Guess I can stop saving for that belt swap..lol.

[Bushrat]

Can anybody tell me the advantage of or why they use belts in the first place other than built in failure.

[liar]

chains fail also . they stretch and jump teeth . belt are maintenance free , quieter , lighter . bikes have also gone to belts and dropped chains years ago .

[JB_AOL]

Originally Posted by Bushrat

Can anybody tell me the advantage of or why they use belts in the first place other than built in failure.

Depends on the engine, but chains would cause more drag, so on a "lower" HP engine a chain could affect power delivery.

And the big one, belts are cheaper.

[couleefolk]

On our 83 sunbird 1.8l we have lost 2 timing belts. Reason was probably that I didn't do the front seal the first time it went and the belt got soaked full of oil again after a couple of years. No damage to the motor, and the belts are super easy to swap out. The timing belts are pretty durable, as our belt cover on our sunbird was broken when we bought the car, and didn't replace the cover till the second belt blew, and we drive a lot of gravel. On a newer car I would get it replaced before the time they are known to fail.

[elkhunter11]

Originally Posted by liar

chains fail also . they stretch and jump teeth . belt are maintenance free , quieter , lighter . bikes have also gone to belts and dropped chains years ago .

Modern chains last several hundreds of thousands of miles and the vehicle manufacturers have been phasing out belts in the new engine designs.Many companies no longer use timing belts in any of their engines. Some motorcycles use drive belts, but the highest performance bikes, and off road bikes use chains.

[Bushrat]

Was just curious. Constantly hear of timing belt failure but rarely hear of timing chain failure on modern engines.

[6MT]

If it's an interference engine, do you really want to risk a failure? At a catastrophic failure at high revs? I've seen many cylinder head jobs (very lucrative for us) where time and mileage were ignored only to have a high rev belt failure. Then, get the wallet out, baby!!

My advice? Pay attention to the recommended intervals.

Chains? Different matter.

[titegroup]

Originally Posted by Bushrat

Was just curious. Constantly hear of timing belt failure but rarely hear of timing chain failure on modern engines.

One ex -mechanic from a Toyota dealership told me that Tacoma's & Tundra's pretty much need timing belts every 130.00k to 150,00k like clockwork, that would get old in a hurry--$!. A fellow a week ago that has owned a 09" Titan since new with over 450,000k on it told me he hasn't had any major issues with it except normal maintenance things as you would normally expect for a truck with those K's on it & is looking towards a new one. Kudo's to Nissan, by the way they have timing chains/dual overhead cam's/ 32 valves- 5,6 Litre.

[Lefty-Canuck]

I did one in a Pathfinder, one in a VW Jetta TDI and one in an F-150 (chain)

I believe the most critical of all three was the VW, the others were done while in doing other work.

LC

[elkhunter11]

Originally Posted by titegroup

One ex -mechanic from a Toyota dealership told me that Tacoma's & Tundra's pretty much need timing belts every 130.00k to 150,00k like clockwork, that would get old in a hurry--$!. A fellow a week ago that has owned a 09" Titan since new with over 450,000k on it told me he hasn't had any major issues with it except normal maintenance things as you would normally expect for a truck with those K's on it & is looking towards a new one. Kudo's to Nissan, by the way they have timing chains/dual overhead cam's/ 32 valves- 5,6 Litre.

Toyota doesn't use timing belts in the Tundra engines anymore, they haven't used timing belts since they stopped using the 4.7l. The 4.6l and the 5.7l have always used chains. .Toyota started phasing out timing belts over a decade ago.

[titegroup]

Originally Posted by elkhunter11

Toyota doesn't use timing belts in the Tundra engines anymore, they haven't used timing belts since they stopped using the 4.7l. The 4.6l and the 5.7l have always used chains. .Toyota started phasing out timing belts over a decade ago.

That's good to know, you're up on your tech-more than me on Toyota's.

[sako1]

Originally Posted by elkhunter11

Modern chains last several hundreds of thousands of miles and the vehicle manufacturers have been phasing out belts in the new engine designs.Many companies no longer use timing belts in any of their engines. Some motorcycles use drive belts, but the highest performance bikes, and off road bikes use chains.

Many newer timing chain systems cause huge problems fairly early on. Ford trucks for example. Numerous others are stretching early and causing timing issues as well as misfires. Part of the problem is people are extending their oil change intervals,not necessarily their fault because of how the vehicles oil life monitor works.

[elkhunter11]

Originally Posted by sako1

Many newer timing chain systems cause huge problems fairly early on. Ford trucks for example. Numerous others are stretching early and causing timing issues as well as misfires. Part of the problem is people are extending their oil change intervals,not necessarily their fault because of how the vehicles oil life monitor works.

And some people simply reset the oil change monitor to make the alarm go away, and then they forget and run the oil way longer than they should. I know someone that put over 20,000km on a brand new vehicle without changing the oil, when the recommended interval was 8,000km.

[sako1]

Originally Posted by elkhunter11

And some people simply reset the oil change monitor to make the alarm go away, and then they forget and run the oil way longer than they should. I know someone that put over 20,000km on a brand new vehicle without changing the oil, when the recommended interval was 8,000km.

Most of the time it's not people reseting the monitor,but the monitor itself. Depending on driving style ect, many monitors don't reach 0% oil life until 15 000km +

[elkhunter11]

Originally Posted by sako1

Most of the time it's not people reseting the monitor,but the monitor itself. Depending on driving style ect, many monitors don't reach 0% oil life until 15 000km +

And if a premium synthetic oil, and a high capacity oil filter were being used, it likely wouldn't be an issue, but many people either have no clue about oil or oil filters, and they really don't care, they just want the cheapest oil change possible.

[ren008]

Just changed out the belt on gfs V6 Sportage. Tough job but with water pump replacement took about 7 hours, will be way quicker next time. Reccommended interval was 96k and hers had just over 100k. Belt was seriously scary looking cracked and teeth starting to go.... Dont ignore it!!

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