Timing belts

Both my 2004 Sonata and 2005 Elantra are at 60000 miles meaning the warranty demands timing belt replacement. My question is how much over the stated mileage can I go with out worrying about belt failure. In California it isn't even required because of state requirements and I assume I have the same factory belt.

 

Not sure of the safety factor, but you risk damaging the engine should one break. Not sure if your engines qualify, but one some, when the belt breaks, valve and pistons intermingle, not good. It has nothing to do with emissions, it has to do with being stranded on the side of the road. Hondas are 90K.

 

Just Bill has the scoop on this pretty much.

What he was referring to is what is called an "interference" engine. What that means is if the belt should break, or even get slopy enough to allow the cam timing to get out of whack, the pistons can be driven right through the top of the pistons, or other damage.

How far can you go without worrying? are you a gambler?

Do it at your earliest opportunity. Things could happen today, they may not happen for years. No way to to tell.

That is why I asked; are you a gambler?

 

I'de like to see that happen.

Nap, you may need some of this after that comment...

http://kalecoauto.com/index.php?main...&products_id=6

 

I checked the Gates site and they are both interference engines (aka valve-benders).

FWIW, if I owned a valve-bender and it recommended 60,000 mile replacement I would do it at 50,000.

My $.02 worth.

 

I like that. Have you ever heard that radio show where they called this girl and were selling her all sorts of things like this> Hilarious.

from http://www.leemyles.com/articles/int...ing-belts.html



fromhttp://www.enginebuilder.ca/InterferenceEngines.htm



granted, most of the time you end up with bent valves but it can break a piston or even bend a conn rod.

The point is; it is better to change the belt before you have a problem. It can be very expensive if you wait until after.

 

60,000 isn't very much my 1999 Acura CL 3.0 calls for replacement at 105,000 I changed it at 104,500 and it was in perfect condition.

 

For anybody driving a car with an interference engine (aka valve-bender) who wants to roll the dice that the belt won't break by delaying the replacement until at or beyond the recommended interval I say, "Go for it!". BUT, you're not allowed to whine and complain when the bill for replacing the belt ($300) turns into a bill for replacing the head ($1500) - OR for my tow bill.

 

Are these belts based on mileage or is time a factor? My dealer toldl me it had to be replaced at 60,000 miles or 4 years.

 

Mostly mileage, but your dealer has a point

As for getting more than the recommended mileage out of a timing belt, of course you can
That mileage (60K or whatever) is recommended because it's highly unlikely it'll need replacing before then
You could get twice that*

But with an interference engine, you are taking a huge risk as TowGuy points out
*(before destroying your engine)


Interestingly enough, some manufacturers with non-interference engines do not have a recommended replacement schedule....they say "when it breaks"

As it never breaks at the dealers or the service station, or in your driveway, it's always when you are on a long trip or in front of the Post Office on Saturday morning, or when you absolutely, positively can't be late and/or don't have the extra cash for a tow and replacement...I'd strongly suggest doing it anyway

 

git R Done.........

 

age is probably just as hard on the belt as mileage but it probably isnt a factor for most people that drive atleat 10k a year, personaly I would not be to concerned about driving one 70k even if its an interference engine as they usually do not fail until over 70k or more miles.

 

Do any of you think a timing belt might last longer if you never use the "passing gear"?

 

It's possible the life could be extended some. Ditto if you did a lot of driving long distance where the number of start cycles is lessened. Cruising along at 70 miles an hour puts less strain on the belt than when you turn the key on a cold engine.

 

What is an interference engine? Never heard that term before.

I have a 1991 Plymouth Acclaim that I just replaced the timing belt on. It had about 143,000 miles on it. The belt had been making an obnoxious noise for a long time. I finally took it to a shop to find out what the noise was. Till now, I always thought timing belts were chains. This was rubber.

 

In an interference engine the design allows for the valves and the piston to move through the same space, but not at the same time. If the timing belt breaks, the valves stop moving and any that are "open" can be struck by the moving pistons. If you go here:

http://www.gates.com/downloads/downl...older=brochure

And click on "Free running or interference engine", you'll get a good description and diagram.

 

Thanks for that link. I Googled interference engines, but didn’t come up with anything as good as that. Paints a very good picture. Makes a guy wonder why they would design something like that. Also, makes me wonder if I’ve sustained some damage to the valves by running such a loose timing belt for so long. The belt made a horrible noise. It’s replaced, and running quiet now.

 

According to the chart, yours is not an interference engine; you could theoretically run it until the belt broke without damage.

Plenty of discussion on the pros & cons of the design, but I don't like the concept. With a timing CHAIN, maybe; but not with a belt.

 

So, a rubber timing belt is not an indication of interference engine? Thanks for that info. I couldn’t find that info as to whether it was an interference engine or not, but now see it.

 

No. I'm not sure what % of engines with belts or chains are interference, but it's not an indicator. Some manufacturers using interference designs have switched from belt to chain, presumeably for reliability.

 

Well, I’ve learned something here. That’s what I like about these forums. Something to make sure I don’t get the next time I’m shopping for a car. Don’t get an interference engine.

That chart says to replace the timing belt at 60,000 miles. I got 140,000 out of it. More than twice the recommended milage. I was probably lucky.

About 20 years ago, I bought a new motorcycle. With less than 1,500 miles on it, I had to take it back to have the timing belt replaced, and it was a chain.

 

A lot of people simply drive their car until the belt breaks, either intentionally putting it off or through ignorance - big surprise when they've never heard of the interference engine ramifications. I HATE going out on a call to pick up an older Honda (many models with interference engines) from the side of the road where the description is, "it just died" and the car has like 125,000 miles on. I try to avoid answering technical questions so I don't have to be the one to tell them they might be in for a $1500 repair.