Timing belt interval?

[Pablo808]

So I have a 95 300zx N/A with 72k miles. Everything stock. Before my brother owned it he purchased it back in 2014. The previous owner kept it in immaculate condition. By the time my brother purchased it, the mileage that was on the odometer read 31k. If I remember correctly, he said he kept it with scheduled maintenance. Don't know if that means he did the timing belt or not.
Anyways, heard it was a 60k interval change or 5-6 year interval for these cars.
Could I keep going at changing it once it hits 90k? I kinda mind if I have to do it real soon since it looks a big job for these cars, also me having to look at other peoples cars too. I'll try to pop up the top timing cover today to look at.

[NolimitZ32]

Look at it this way: If it pops, your immaculate Z becomes a really pretty paperweight. So is it worth it? If you have the knowledge and experience to be able to look at the belt and tell if it needs changing than do that otherwise you should probably change it.

[Pablo808]

Look at it this way: If it pops, your immaculate Z becomes a really pretty paperweight. So is it worth it? If you have the knowledge and experience to be able to look at the belt and tell if it needs changing than do that otherwise you should probably change it.

Later today. 'll probably pop the top timing cover. Yes I know these are non interference motors. It's been 23 years since 1995 and the previous owner(s) had to change it at least once. Just been avoiding to do another timing belt job since I've got other peoples cars to do.

[Pablo808]

Look at it this way: If it pops, your immaculate Z becomes a really pretty paperweight. So is it worth it? If you have the knowledge and experience to be able to look at the belt and tell if it needs changing than do that otherwise you should probably change it.

I was just asking if it's pretty urgent at 60k to change your timing belt.

[amc49]

FYI, most timing belts changed material around '98-00 to begin to use hypalon in the belts and the typical change times then extended from 60K miles to 120K, the belt materials being much stronger. So, depends kinda on if somebody has changed it since the original one. May already have a much longer lasting one on it.

[Pablo808]

FYI, most timing belts changed material around '98-00 to begin to use hypalon in the belts and the typical change times then extended from 60K miles to 120K, the belt materials being much stronger. So, depends kinda on if somebody has changed it since the original one. May already have a much longer lasting one on it.

Okay, well I just looked at the timing belt. I popped open the top timing cover. I didn't notice any cracks forming yet. I can even still see the smudgedwriting on the belt and the arrow indicator. Still says "Nissan" on it. Don't know if it's the actual belt from 1995 or someone replaced it with a newer OEM one. Thinking that it's already been 23 years since it left the factory, someone had to already change it. I'll look at it again in the next 15-25k miles.

[NolimitZ32]

These engines ARE interference, that's why if the belt pops it results in catastrophic damage. On non-interference engines, its not a big deal.

[Ace2cool]

There's plenty of pics on TT.net of timing belts that looked brand new except for the spot they broke.

[amc49]

In my experience they strip teeth with zero warning and the belt will look perfect right up until it happens. There being absolutely no way to tell how old a belt is by simply looking at it commonly. Many will look almost new except for the missing teeth. Of course once they fray or crack it's past time to do it. Although they can break, they commonly don't and why so many people keep trying to start the cars and just tearing up an interference one more and more doing that.

If the starter starts suddenly sounding like it is cycling faster than normal on a non-starting engine with a rubber timing belt STOP! Your only warning there.

[Pablo808]

In my experience they strip teeth with zero warning and the belt will look perfect right up until it happens. There being absolutely no way to tell how old a belt is by simply looking at it commonly. Many will look almost new except for the missing teeth. Of course once they fray or crack it's past time to do it. Although they can break, they commonly don't and why so many people keep trying to start the cars and just tearing up an interference one more and more doing that.

If the starter starts suddenly sounding like it is cycling faster than normal on a non-starting engine with a rubber timing belt STOP! Your only warning there.

I’ll check again, maybe if my days off. First thing, I popped the top timing cover on the driver side and looked on the top of the timing belt to see if I was still able to read it, and it had smudged writing. Then looked on the teeth to see if it was cracked or ripping, and nothing. Flexed it quite a bit to see if it was loosed or stretched and felt okay. Also looked to see if the sides of the belt was degrading with white rope. I didn’t turn the crank to see if all around the timing belt was okay since I didn’t feel like lifting the car on my grassy hill driveway. I believe someone had to change it at least once since a 23 year old belt wouldn’t be lasted up to now.
But I’ll check again sometime. The top timing cover was pretty tight to work on with me even having small hands lol..
Also yes, I’ve had experience on a friend’s car on what a motor sounds like when you try to crank it with a snapped timing belt. It literally just sounds like a freespinning starter when you bench test it.

[Pablo808]

These engines ARE interference, that's why if the belt pops it results in catastrophic damage. On non-interference engines, its not a big deal.

Yeah, I had a few people telling me this was an inter fear ace motor. I’ll try look again when I have time to spin the crank with he top timing cover open to inspect every part of the belt

[NolimitZ32]

Looking at the top of the belt will tell you nothing, as many have already mentioned sometimes the belts will go without warning. If you're going to inspect a the belt it needs to be done on the toothed side and along the edge, if you don;t know exactly what to look for then just staring at it is useless because you likely wont be able to tell.

[Pablo808]

Looking at the top of the belt will tell you nothing, as many have already mentioned sometimes the belts will go without warning. If you're going to inspect a the belt it needs to be done on the toothed side and along the edge, if you don;t know exactly what to look for then just staring at it is useless because you likely wont be able to tell.

Please read ALL what I typed....

When I popped open the top timing cover. I expected every view I could.
First thing first, I saw the smudged timing belt writing w/ the arrow.
Then I checked to see if the timing belt was stretched. Felt like a normal tensioned belt.
Next, I flipped over to inspect the tooth. No cracks, no missing teeth, looked everywhere I could shine my flashlight.
(I couldn't spin the belt since the fan was in the way, nor did I want to jack up the car on a grassy graded hill. )
After that I checked the sides of the belt to see if there was white worn out material sticking out. It was clean.
I'll check the belt in the next 15k miles.

The previous owner before my brother had kept this car all stock besides the staged clutch and kept it clean/ maintained.
Only reason the guy was selling it was because he had a bad left leg so he needed an automatic car.
He had it at 31k miles and that was back in 2014.
Now it's 72k miles.
I'm just trying to throw out that I don't think this is the original timing belt from the factory since it's been 23 years and that from 98-00 someone of the forum pointed out that better material was used for timing belts.
I know inspecting JUST the top of the belt ain't going to do much, but I checked whatever I could with just that top right cover off.

[NolimitZ32]

Enjoy.

[Pablo808]

Enjoy.

Thanks