Timing belt question

As I understand it a broken timing belt will not mean pistons and valves crashing into each other but I'm unsure if other sorts of damage can be caused.

Have you considered doing the job yourself? It could make the job pretty cheap and you will feel pretty good afterwards for having done it your self (I know I do after having done stuff like that).

Kind regards Bruno

WOW, You have a great job potential ahead of you if you can look at a timming belt "on the car" and tell if it is going to fail. (I don't know of anyone that can do that.) Go to Mazda as soon as you can. I'm sure they can use you as soon as you can start. :-) As far as damage, if you don't count damage to your pocket book, the chance that the belt may destroy the front plastic belt covers and the guy that hits you in the rear end when you are in the center lane of a freeway and youe car stops and they are going 70 MPH and following too close. Not too much damage at all. :-)

Bruce Bing '03 LS

Bruce, Do you think maybe he's looking at the fan belt and thinking it's the timing belt?

Yes I guess I am... and as a new Miata owner I am kind of in wonder of the unsuspected ex-prize who left the previous message. Rather than give any helpful insight he decided to make a joke at my expense. I could see the joke and then pointing me in the right direction... whatever. Is the timing belt something I can do? I used to work on BMW motorcycles quite a bit but am not familiar with the Miata... so far. myself?

There is a bit of stuff to remove, but it isn't rocket science. Take a look at

. I managed to do mine, but then I would never get the fan belt mixed up with the timing belt.

My 1995 Mazda 626 has 152,000 miles and the belt has never been replaced. YMMV.

The previous owner of my 1992 said the belt broke around 120,000 miles.

The best guess I've gathered from people here and elsewhere is that the belt is *PROBABLY* good for 100,000 miles and that Mazda's recommendation is *PROBABLY* conservative. As always, YMMV.

Mazda's recommendation is definitely conservative. Let's say the belt breaks at 80,000 miles.

If the manufacturer recommends 60K, then the owner feels guilty for not changing it according to the recommendation.

If the manufacturer recommends 100K, the owner is outraged that the %^$%$^%$ timing belt broke, even though he followed the maintenance schedule.

Still, you should still change the belt at *around* 60K.

When I first started reading this group I remember this subject coming up. It was said that the water pumps often start to fail near 100k and all the same stuff has to come off, so do the belt and the water pump between 80k and 100k.

(No experience myself with this, just remembered it as sounding sensible.)

miker

One would think that Mazda would want the probability of failure before 60k miles to be almost zero. It would have to be VERY conservative for that to be true. I did replace it at 60k but I'm not inclined to at 130k. Any experiences with Miatas?

Why?

zenmartini wrote: >

Ideally if money's no object you want to go with the suggested maintenance schedule, but broke as I am, I'll probably wait until

100,000 miles. Why? Because in California, the exact same timing belt that Mazda says you should replace at 60,000 miles in the other 49 states, they say is good until 105,000 miles there. This has something to do with California's elaborate car regulations, but the fact remains that Mazda wouldn't ship Miatas with a timing belt that they'd expect to fail prior to the manual's scheduled replacement date.

I bought a used '93 and the previous owner had never changed the timing belt. In 2004, at over 100K miles, the radiator sprung a leak. I figured since I was paying for the labor to take the radiator out anyway, I'd finally replace the timing belt and the water pump too. The old belt looked surprisingly good, even after 11-12 years. I was actually more worried about the water pump, and when they had it exposed and the belt off, you could wiggle the shaft laterally so you could tell that water pump would probably have failed pretty soon.

So that's the other suggestion; when you finally do get the timing belt done, while you're in there, replace the water pump too; it's only about a $75 part, but if it fails it'd cost an additional $150-$200 in labor to take off the stuff you need to to get at it, not to mention you might ruin the cylinder head if it overheats.

Yours WDK - snipped-for-privacy@ij.net

Based on my own VERY limited experience (one Miata) and reading collected input of this group and Miata.net, I will personally change timing belt, V belts, Crank seal, Cam seals, water pump and idlers every 100,000 miles. As always, YMMV

Someone said that to conform to California rules, Mazda changed the recommendation in California to 100,000 miles, does anyone know if that's true or not?

I suspect the California belt is the same part number, isn't it?

Sorry, I posted before reading W. Kiernan's excellent post on the topic.

Actually, I understand from Miata magazine that while California requires the belt must last 100 kmi, Mazda still requires the belt to be *inspected* after 60 kmi. They felt that if they go through that trouble, a mechanic might as well replace it.

I do not remember seeing any posts here reporting a belt breaking before

100 kmi though. All the ones I remember were over 100 kmi.

Of course, not replacing at 60 kmi has the disadvantage that you cannot blame Mazda for the chain collision you caused having your belt go out at 70 kmi in the middle of a busy freeway in front of that SUV that was not on the cell phone at the time. The legal responsibility will be all yours. :)

Leon

Because I'm not fond of the idea of waiting for the belt to break, leaving me stranded God knows where or when. And yes, the Miata is a non interference engine, but that doesn't mean that a flailing belt can't cause other damage.

Personally I changed my belt at 75K. (I boutght the car with 68K and the original belt) It looked fine and would probably have gone another 25K, but now I don't have to worry about it for another 75K.

Also on NBs the valve clearances should be checked at 60K and if any need changing you might as well do the belt then since a lot of the work overlaps.

Dunno how things work over there in "The land of the free", but over here if you run into the back of another vehicle, you are almost certainly in the wrong. (possible exceptions are if the driver in front is drunk, driving unlicensed, reversing, or deliboratly attempting to cause an accident). Some idiot talking on a mobile driving into the back of a your car when if broke down would be in the wrong.

Loosing power while accellerating into a small gap in traffic, or crossing lanes could see you in the wrong. Also breaking down in the middle of nowhere, or the middle of somewhere bad would not be fun.

True, but if you're driving a Miata and he's driving an 18 wheeler does him being wrong make up for you being dead?

Here, and I suspect where you are also, people tend to follow much too closely so if you're driving at speed and the timming belt breaks you do have a very real possibility of being hit from behind.

Since we're driving Miatas, it's an almost sure thing the other guy will be bigger and heavier and, right or wrong, we'll sustain the greater injuries.