Timing Belt replacement

[kkim]

I am doing research about buying a NSX in the future and I've read of the caution of having the timing belt changed due to mileage and time. I know it's a scheduled maintenance to prevent failure, but how long do these belts last before failing?

My main concern is... Has anyone had a timing belt actually fail and under what conditions? If you have had them fail(sorry to hear that, btw) and, gulp... what was the repair cost?

thanks for any info you can provide.

 

[matteni]

I had mine replaced well after the time limit but less then 1/2 of the mile limit.

I would be interested to hear of any belt on an NSX (or any other Honda) that failed after a time limit but before the mileage limit.

I suspect there has not been any failures attributable to timing belt time and that Honda publishes the dates just so they don't have to test anything. They have no vested interest in making the maintenance schedule just based on mileage and not time. Just like the stock market there are 2 drivers for automotive maintenance: fear and greed.

There has been a lot of hearsay but I have not seen any evidence to the fact. Think about it - if it were that important there would be "born on dating" or "expiration dating" on the parts packaging! BTW - before anyone gets their dander up on this - remember Honda is no better or worse then anyone else in this respect and we haven't seen any evidence that an NSX timing belt failed by age alone OR that Honda destroys new parts voluntarily based on age alone.

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Nick M

91' Red/Black with Many Mods
99' Honda Odyssey with Many Kids

 

[Jimbo]

There have been timing belt failures and I've read them here. You may wish to do a search. There have also been other timing belt failures with other cars that use a similar belt design.

In general, I suspect these belts have a factor of 2X with their safety recommendations. This would accomodate variabilities due to climate and usage.

There is absolutely no reason, IMHO, to push the recommendation. The potential cost of engine replacement significantly outweighs the cost of belt replacement.

Since it's a rubber, composite component, it's hard to make a definitive prediction on life. It depends on the raw materials used in a certain batch of belts, it depends on climate (humidity, temp), how dirty or dusty the environment is, how hard you drive it and many other variables.

Bottom line...

If it's due, change the belt.

-Jim

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1992 NSX Red/Blk 5 spd #0330
1991 NSX Blk/Blk Auto #3070 (Sold)
1974 Vette 454 4 spd Wht/Blk
1976 Honda Accord 5 spd, 3 door Blue/Blue
1977 Honda Accord - Custom - Under Construction
2003 MINI Cooper S - On Order - All Black
1986 Chevy Suburban
http://homepage.mac.com/jimanders/PhotoAlbum1.html

 

[nsxtasy]

Originally posted by kkim:
how long do these belts last before failing?

For belts where the mileage has not reached the change interval, I'm sure there is no way to predict exactly how long any particular belt lasts, that it will follow a probability distribution. Honda probably has an expectation for how long they might last. Some might start to fail at, say, eight years old, and others might last ten or twelve or longer. They won't all fail at the same time.

Originally posted by kkim:
Has anyone had a timing belt actually fail and under what conditions?

Mark Basch has seen several timing belt failures.

Originally posted by kkim:
If you have had them fail(sorry to hear that, btw) and, gulp... what was the repair cost?

I don't know, but I am sure it is much, much more than the cost of the timing belt replacement. For example, a new 3.0-liter engine costs around $18K and even a used one generally runs around $5K or so. Plus labor, of course.

While you can speculate on the reasons for it, Honda's recommendation is quite clear: 90K miles or 6 years for the '91-96 NSX, 105K miles or 7 years for the '97+ NSX. If you're going to continue driving beyond their recommended replacement interval, you are taking a risk. In order to save the $1200 cost of a timing belt replacement, you are risking a failure that could cost you $6-20K. How would you feel if you suddenly found yourself facing a repair bill that high?

The chance of a failure goes up over time. At what point is this risk no longer worth taking? Honda says that a timing belt will last six years. Do you want to drive one until it's eight years old? Ten years old? Twelve to thirteen years old (the age of the original belt in any '91)? As Clint Eastwood said in Dirty Harry, "you've got to ask yourself a question--Do I feel lucky?" Your engine, your money, your choice.

[This message has been edited by nsxtasy (edited 04 February 2003).]

 

[kkim]

Thank you all for your replies so far. I appreciate you taking the time to answer my basic newbie stuff.

However, I understand the need for the scheduled maintenance and the recommendations that Honda/Acura makes in regards to this engine.

My original question was for belts that have actually failed and under what conditions. I'm just trying to get a feel as to what is reasonable and prudent to expect from the life expectancy of a crucial rubber belt based on actual failures. Like anyone else, I don't want to end up with a destroyed engine, but on the other hand, how critical/acurate is the mileage/time recommendations that is spelled out by the service manual.

I've heard of timing belts for e30 BMWs fail at 35k miles. For Toyota Camrys, they don't have recommendations for ever changing the belts under normal usage. I'm sure the truth for the NSX lies somewhere between these 2 extremes. I'm just trying to figure out where that truth is based on actual incidents of failures.

I did a search, but was unable to came up with posts of any actual timing belt failures.

 

[Nsx Service Girl]

Have I seen Acura timingbelt failures? You betcha. On an NSX? Nope. My NSX clients are much too saavy for that. These cars have interference engines, and several of these components drive off of each other. I've encountered failures from the waterpump locking up and "throwing" the belt, or the distributor seizing and doing the same. Also from the belt breaking because it was just too darn worn, old or cracked. The resulting damages have varied from just installing a new belt, to bent intake and exhaust valves.
Appears the rate of speed the car was going when the belt brokes does play a part in the amount of damage sustained. In every instance, the cars had to be towed in (not convienent). Originally we were replacing belts at 60K, now we have models that aren't recommended for replacement until 105K. I'd say that mother Honda IS doing her homework!

 

[kkim]

Nsx Service Girl- Thanks for your input. You bring up a related question, though... now that the intervals have been upped to 105k, what is the reason? newer belt design and if so, if I were to replace a timing belt on a 91-92 NSX, would it be good for 60k or 105k?

If it's a design update, can the newer design belts work on the older cars?

 

[Vytas]

Woodwork had mentioned that the belt may not always break. The teeth on the belt can sheer off as well.

 

[Tony Montoya]

I would like to know if an NSX belt has failed with less than 30k miles on it.

 

[Jimbo]

Tony,

You mean regardless of mileage?

Keep in mind that for rubber (or more precisely, elastomeric) components, time can be just as important as usage for gauging lifetime.

I don't think I've ever heard of a NSX timing belt failure that was within the prescribed time/mileage limits. Perhaps MB or someone else has?

This topic comes up from time to time and I'm always at a loss to understand why. I think we all realize that the belts have to be replaced at some point. It's not like you're really going to save $1200, you're only going to potentially defer that expense to a later time. Unless, of course, you want to buy and NSX, drive it for a year and then sell it.

If you plan to keep the car for a long time the savings are nil. A long term NSX owner might have replace the belts 2 or 4 times during their ownership. Where's the gain in pushing it?

When I bought my first NSX, the first thing I did was to schedule an appt and have the car gone over and the TB and WP done (along with other things). There's a certain peace of mind in knowing that you don't have to worry about it. I sold the car after a year or so, but I don't regret the expense.

When I bought my 2nd NSX (a 92 with about 9K orig miles), I did the same thing and was happy to do so. I replaced the timing belt and water pump. It wasn't like I didn't drive it until I did it, but as soon as I reasonably could, I changed it.

Could I have went a few more years? I'm sure I could have. But, I also know it would have made me crazy. Every time I would redline or push the car, it would have been in the back of my mind. It's just not worth it.

The NSX is very reasonable in maintenance costs considering the type of car and the level of performance you get, and if the cost of the timing belt replacement is on your mind anymore than the cost of changing the oil and filter every 3K miles, then clearly this isn't the car for you.

Regards,
Jim



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1992 NSX Red/Blk 5 spd #0330
1991 NSX Blk/Blk Auto #3070 (Sold)
1974 Vette 454 4 spd Wht/Blk
1976 Honda Accord 5 spd, 3 door Blue/Blue
1977 Honda Accord - Custom - Under Construction
2003 MINI Cooper S - On Order - All Black
1986 Chevy Suburban
http://homepage.mac.com/jimanders/PhotoAlbum1.html