Do I need a new timing belt?

[SLarsen]

I've just gone over 30,000 miles on my 2002, yellow NSX. The Acura dealer is recommending a new timing belt. Acura recommends replacement at 90,000 miles OR every six (6 years). At ten years old, I'm well past that. My questions are:
1. Has anyone had a timing belt break on an NSX? If yes, under what circumstances? (e.g. mielage, age)
2. When did you change your timing belt? (Again, age and mileage most helpful).
3. While I assume mine will be okay for another 30-40K miles, does the fact that I live in Phoenix (where our air is hell on rubber anything) change that? Is the timing belt exposed to the dry, rubber eating Phoenix air?

Your responses are welcome and appreciated. Obviously, if I can avoid or delay this rather large expense, I would.

Steve Larsen

P.S. Just found the article on the wiki after posting this. It is very helpful. Still curious on anyone's answers to the above, but it looks like I absolutely should replace it.

 

[L_RAO]

An even bigger expense would be to have to replace the entire engine.

I've only seen timing belts go bad on neglected B-series Hondas.

Ride out the current belt at your own risk.

 

[shawn110975]

+1 Agree with L_RAO

a car that is driven Daily can go a lot longer than a car that sits in a garage. now there are a few people on here that just now changed their 1991 NSX TB/WP without naming names and the 20 year old belt with 150K miles looked almost new next to the brand new one.

but to rebuild the whole motor is alot more than a TB/WP job.

"drive at your own risk" statement should sing in your mind while your driving your Dream car.

 

[PHOEN$X]

Hi Steve, below are some more discussions on this subject. Personally, I would error on the side of caution and adhere to the recommended service schedule. I had SOS replace a timing belt on my 97 NSX (among other services) and I was very satisfied with their service. They work on more NSXs than any Acura dealerships, and I wouldn't trust my NSXs to any other shop.

http://www.nsxprime.com/forum/showthread.php?t=120008
http://www.nsxprime.com/forum/showthread.php?t=64568
http://www.nsxprime.com/forum/showthread.php?t=47797
http://www.nsxprime.com/forum/showthread.php?t=1875

By the way, I would recommend getting the crankshaft pulley shield installed at the same time you have the timing belt replaced, since you will have to remove the pulley anyway.

 

[Honcho]

Many threads on this and many different viewpoints, including even at Honda where the JDM and Euro-spec TB maintenence intervals are miles only. Still, I fall in the follow the recommendation group, since a failed belt can be an expensive event.

1. Yes. I have heard of a few from reliable sources, though not very many. I can't remember the details this long after I did the initial research, but I believe most of the cars were in hot climates and run hard with poor maintenence. More likely than a clean break, however, is that the belt will fatigue and stretch, which can cause it to skip a tooth or two. This means bent valves at least.

2. My 1991 had its first one done in 2006 @ 60,000 miles. I will be doing it this winter, since it has been 7 years. Current mileage is 87,000 and probably will be close to 90,000 by the time I do the belt (I daily drive my NSX).

3. Yes. The timing belt is made out of rubber and nylon. It is essentially nylon cords cast in a tooth-shaped rubber mold. The strength of the belt is mostly in the nylon cords, but the rubber provides support and flexibility as well. Heat and low moisture kills rubber. I'm sure you have seen what prolonged heat can do to plastic. The belt is sealed within the timing case by rubber gaskets, but these are simply to keep dirt out of the chamber. The belt however still is exposed to all ambient air and heat, plus engine heat and vibration.

Given the very diverse climates of the USA, this may be why Honda gave us a time interval. Japan simply does not have a climate similar to the desert Southwest, so perhaps Honda felt there was no danger to the belt from heat/dry rot.

I thought the TB service interval for NA2 cars was revised to 7 years?

I've just gone over 30,000 miles on my 2002, yellow NSX. The Acura dealer is recommending a new timing belt. Acura recommends replacement at 90,000 miles OR every six (6 years). At ten years old, I'm well past that. My questions are:
1. Has anyone had a timing belt break on an NSX? If yes, under what circumstances? (e.g. mielage, age)
2. When did you change your timing belt? (Again, age and mileage most helpful).
3. While I assume mine will be okay for another 30-40K miles, does the fact that I live in Phoenix (where our air is hell on rubber anything) change that? Is the timing belt exposed to the dry, rubber eating Phoenix air?

Your responses are welcome and appreciated. Obviously, if I can avoid or delay this rather large expense, I would.

Steve Larsen

P.S. Just found the article on the wiki after posting this. It is very helpful. Still curious on anyone's answers to the above, but it looks like I absolutely should replace it.

 

[A.S. Motorsport]

Replace it!
Seriously you don't want to see a NSX engine that snapped the belt at any rpm, I've a piston some where that has a valve welded on to it!

shawn110975,
Completely right! driving a car is MUCH better than letting it sit in a garage even a nice garage!

Honcho,
As far i know it remained 6 years.
EDM norm is also 6 years.

 

[tabasco]

Did my 2000 with 12300 miles last fall. $1,900 at Acura dealer.

 

[nsxtasy]

Honcho,
As far i know it remained 6 years.

Not true. Beginning in 1997, Honda changed the recommendation for the timing belt service interval to 105K miles or 7 years, whichever comes first. This applies to all 1997-2005 NSXs, including NA1 and NA2 models.

Some people have claimed that this means the 1991-1996 NSX can also go with the longer mileage. For all I know, they may be right. Personally, I think the people who get in trouble are not going to be the ones who let theirs go to 105K miles or 7 years, but rather, the ones who let theirs go beyond either of those numbers.

There are two things to keep in mind when considering whether or not you want to exceed Honda's recommendation for changing the timing belt. (1) How much will you benefit by extending the interval? If a timing belt change costs $1800, changing it every 7 years instead of every 9 years means a savings averaging $57 per year, i.e. $257/year vs $200/year. (2) How much extra will you pay if you extend the interval and the timing belt fails? If that happens, chances are that you will need to replace or rebuild your engine. I spent around $10K total to replace my 3.0-liter engine with a used one of similar mileage. (It wasn't because I waited too long to change the timing belt, it had another cause, but the net effect was the same.) So, do you really want to risk spending $10K in order to save $57 per year?

Personally, IMO, replacing a ten-year-old timing belt on a car kept in Phoenix is a no-brainer. Just do it. But it's your car and your money, your decision, and you'll have to live with the consequences. If you want to take the risk, that's up to you.

When changing the timing belt, the water pump is usually changed, because it's all the same labor to do either, and water pumps do fail. Note that the coolant is flushed when changing the water pump, so that resets the interval for changing the coolant. (On a '91-96, that would mean you don't need to do it for another 30K miles or 2 years, whichever comes first; I don't know whether the '97-05 recommendation is the same.) I would recommend replacing two other items at the same time. It's good preventive maintenance to replace the cooling system hoses at this time - the two big ones at a minimum, and perhaps all 22-23 of them. Old cooling system hoses do fail, and replacing them on a preventive basis could prevent you from being stranded somewhere. Also, doing it at the same time as the water pump means savings in coolant and labor. Finally, consider replacing the harmonic balancer (crankshaft) pulley at this time, as old ones can come apart and wear into and through the timing belt cover, causing the timing belt to break. (THAT'S what happened to my car.)

 

[blvnhim]

Question: When you buy timing belt, comes with a little wrapper ----part #, made in japan, etc. How do you know when that belt was made. In relation to other posts, could that belt have been made in say '05, been on warehouse shelf and be no better than the supposed one on a car "in a nice garage" ? Are they still making them today for NSX? Who has the info? Thanx

 

[comtec]

Had it replaced on my 2002 this year at 29,000.

Mike

 

[davidf]

Question: When you buy timing belt, comes with a little wrapper ----part #, made in japan, etc. How do you know when that belt was made. In relation to other posts, could that belt have been made in say '05, been on warehouse shelf and be no better than the supposed one on a car "in a nice garage" ? Are they still making them today for NSX? Who has the info? Thanx

I don't think TB's have a shelf life expiration date. Their sealed in their factory wrapper keeping moisture and elements out.

 

[Meeyatch1]

I am curious how many times this same question has to be asked and answered before people will take the time to find and read the dozens of other posts about this exact same topic?

 

[surferX]

I would replace it and you won't have to worry about it for another 7 years. I replaced mine at 8 years with 80k miles. I've had friends that pushed it with other cars and blew up their motors. I wouldn't push it on the NSX. Once a mechanic recommended it, I had it done. IMHO, the risk is not worth the reward as you are going to have to do it at some point anyway and your car is 10 years old.

 

[SLarsen]

Thank you all for the highly valuable information. I'd read the stuff on the wiki, but its great to get such good, new, updated information. [Is there an easy way to add this thread to the wiki?]

I want to especially thank PHOEN$X for the reference to Science of Speed. I'd forgotten that was an option and sounds like a very good one. Honcho, your info on the makeup of the belt was really useful, thank you. Nsxtasy, not sure I agree with you math, but I get the point - cheap insurance.
So, I'm going to go ahead and do this, sell another story or two, and make it happen somehow.
Oh, and for whomever it was that wondered about garage car or daily driver, the NSX is my daily driver.
Thank you all again!
Steve

 

[jond]

2. When did you change your timing belt? (Again, age and mileage most helpful).

I changed it the first week I got the car. It had 40,000 on the belt, but was 9 years old.
Changed it again after 80,000 miles(120,000 on car, 80,000 since last change).

I'm not going to try to save a dollar and blow up a $30,000 engine.

 

[tbnsxt]

I changed it the first week I got the car. It had 40,000 on the belt, but was 9 years old.
Changed it again after 80,000 miles(120,000 on car, 80,000 since last change).

I'm not going to try to save a dollar and blow up a $30,000 engine.

Well you would be saving about 1300 dollars.

As said earlier even an "old" timing belt looks brand new when compared to the new one. The timing belt is in a sealed compartment keeping it safe from the elements. It is not like the ac compressor belt that is just hanging out in the open. I would say since you live in a super dry area where dry rotting is a problem your 30k mile belt may be worse than say some one who lives in a humid area with a 60k belt. This is where I could see age of the belt being more of a concern. You can ride it out longer at your own risk but you can't go wrong with replacing it.

 

[jond]

Well you would be saving about 1300 dollars.

As said earlier even an "old" timing belt looks brand new when compared to the new one. The timing belt is in a sealed compartment keeping it safe from the elements.

Actually my bill was $3,300, but I had a bunch of preventive stuff done at the same time.
I had the timing belt break on my Ford ranger beater last year. There wasn't even 100,000 on the belt. Luckily with that engine, you can't hurt it, there's no valve overlap(or horsepower). Blow the belt on the NSX, and it's going to cost you. Scratch the cylinder wall and you're going to pay $$$.

 

[1991NSX]

Yea, 7 yrs is VERY reasonable for a sportscar/exotic for the TB interval. AND $1,900 ish isn't too bad for all that they'll do to the car.

 

[Hugh]

Shit! You're supposed to change the timing belt?

 

[jaybird]

OK - I've got a 2001 with 11k miles on her - and will get the TB work done. So, question is, what else should I have done at this time? This car is like brand new - but, while they are doing the TB, I might as well have them to anything else that is advised. Much appreciate the advice! Thanks, Jay

 

[Honcho]

OK - I've got a 2001 with 11k miles on her - and will get the TB work done. So, question is, what else should I have done at this time? This car is like brand new - but, while they are doing the TB, I might as well have them to anything else that is advised. Much appreciate the advice! Thanks, Jay

Jay-

The components being 10 years old, you should think about doing some other stuff that will save labor costs down the road. Here is what I am having done this winter in addition to the TB/WP service, but note that many of my components are 20+ years old.

Crankshaft pulley
All rubber seals (valve covers, spool valves, oil cooler, head dowels, etc)
Two cooling hoses near oil cooler (car overheated at track- recommended by Acura to replace)
Timing belt tensioner, spring and bolt
Drive belts
Rear main and crank seals
Cam plugs and seals
Spark plugs
Thermostat (car overheated at track- recommended by Acura to replace)
SoS LMA kit
Valve adjust (sometimes included with TB service)
Fuel filter
Air filter
Oil change

The recommended interval on the pulley is every other TB job, so if you have your original pulley, I would replace it. It is a known failure point. Same interval with the cooling hoses. So if you have your original hoses, it's time to change them. I doubt your valves have gone out of spec with only 11K miles, but you can have them checked.

 

[clr1024]

Jay-

The components being 10 years old, you should think about doing some other stuff that will save labor costs down the road. Here is what I am having done this winter in addition to the TB/WP service, but note that many of my components are 20+ years old.

Crankshaft pulley
All rubber seals (valve covers, spool valves, oil cooler, head dowels, etc)
Two cooling hoses near oil cooler (car overheated at track- recommended by Acura to replace)
Timing belt tensioner, spring and bolt
Drive belts
Rear main and crank seals
Cam plugs and seals
Spark plugs
Thermostat (car overheated at track- recommended by Acura to replace)
SoS LMA kit
Valve adjust (sometimes included with TB service)
Fuel filter
Air filter
Oil change

The recommended interval on the pulley is every other TB job, so if you have your original pulley, I would replace it. It is a known failure point. Same interval with the cooling hoses. So if you have your original hoses, it's time to change them. I doubt your valves have gone out of spec with only 11K miles, but you can have them checked.

Are you changing the LMA's because your think your's are worn, or you just want the updated design with less ticking?

 

[Honcho]

Are you changing the LMA's because your think your's are worn, or you just want the updated design with less ticking?

My car is sounding a little tappy, but that could be the valves, which have about 20k on them since the last adjustment. I am mostly replacing because the LMA issue is a "when" not "if" failure. As the head will be opened up during the TB service, it just makes sense to replace them now rather than have to pay labor again to replace them when they finally fail. I got to examine a bad LMA at the NSXPO tech sessions and now that I understand the nature of the flaw, it made a lot of sense to get the kit and never worry about it again. I daily drive and track my NSX, so I need 100% reliability at all times in all conditions.

 

[clr1024]

My car is sounding a little tappy, but that could be the valves, which have about 20k on them since the last adjustment. I am mostly replacing because the LMA issue is a "when" not "if" failure. As the head will be opened up during the TB service, it just makes sense to replace them now rather than have to pay labor again to replace them when they finally fail. I got to examine a bad LMA at the NSXPO tech sessions and now that I understand the nature of the flaw, it made a lot of sense to get the kit and never worry about it again. I daily drive and track my NSX, so I need 100% reliability at all times in all conditions.

I didn't realize the LMA's were prone to failure just that the newer ones were a better and quieter design. I also did realize it was a when not if failure. How common are LMA failures?

 

[Larry Bastanza]

I didn't realize the LMA's were prone to failure just that the newer ones were a better and quieter design. I also did realize it was a when not if failure. How common are LMA failures?

Not very.... Replaced three sets in 9 years, all high mileage abused engines.

When I do replace them, the SoS parts are great.

Regards,
LarryB