Superficial cracks on timing belt? (1 Viewer)

[wvrx]

I’ve wanted a 100 series rig for a couple of years now...finally got a 2001 model with 210k miles, I have a carfax documenting a timing belt replacement at 90k miles in 2007. The guy I purchased it from said his parents had water pump issues and thinks the timing belt was replaced ~150k miles or 4-5 years ago, but has no paperwork to back it up.

Truck runs great, I pulled a cam cover to look at the belt and found hairline cracks on the outside surface. Has anyone seen their belt look like this? In my many Honda’s that I’ve done a TB in, they’ve all looked fairly new and I’ve never come across a belt with visible cracks.

That being said, would you consider this a ticking time bomb, or drive for another 10-20k miles and change it? Financially I can’t swing the TB until a couple of months from now, but would appreciate any thoughts you may have since you guys are much more experienced in land cruisers than I.

 

[TXLX007]

Send it.

 

[nukegoat]

Its probably fine but def old

 

[gatormark91]

Nothing in life is guaranteed, but there have been photos of way worse belts on here. I'd not worry, if it were my truck, but I'd not push it any farther than I had to.

 

[Sandroad]

Good work actually looking at the belt. Based on what I see, I’ll guess it’s the belt that was installed in 2007 at 90k. It does not look like a 4 year old belt with 60k. My OEM belt had no cracks when I replaced it at 100k. Since we don’t know anything else about the belt and tensioner, get it replaced as soon as you can afford it. Couple of months should be fine, so long as the tensioner and pulleys and water pump are quiet.

 

[2001LC]

FWIW, It's easier to pull RH cam cover to get better look. Turning crank, inspecting total length of belt, would be good idea. By "most" accounts in mud, a T-belt break of non VVT engine won't interfere (piston to valve), just leave you needing a tow. A break usually happens under-load, so drive with lite foot.

 

[wvrx]

Great thanks for weighing in! I’ll plan to change it when I can do it right the first time and use Aisin parts.

I was tightening my valve covers when I randomly figured i’d pull a couple of 10mm bolts and take a look...will go from the passenger side next time!

 

[97 AZ LC]

By "most" accounts in mud, a T-belt break of non VVT engine won't interfere (piston to valve), just leave you needing a tow.

Most? I would have said it was all. Can you point to a non-VVT that interfered? Here or elsewhere.

 

[2001LC]

Some with non VVT have said engine blew when belt broke, but never showed prof. So I say by "most" accounts.

With respect to the VVT engine being interference. A service manager at Toyota Dealership, that impressed me with his knowledge of the 2UZ. Told me of a VVT engine the Dealership had to replace (buy for the client), due to tech error. He said tech used the "T" mark to set cams druing timing belt job. Very few service manager have enough knowledge of these engine to even know about the "T" mark. So his story rang true, as did all info he gave me.

This may by due to slight change in piston. The VVT has 10:1 as opposed to 9.6:1 compression of non.

 

[Travis Bickle]

Should be fine but change it sooner than later.

 

[97 AZ LC]

Some with non VVT have said engine blew when belt broke, but never showed prof. So I say by "most" accounts.

With respect to the VVT engine being interference. A service manager at Toyota Dealership, that impressed me with his knowledge of the 2UZ. Told me of a VVT engine the Dealership had to replace (buy for the client), due to tech error. He said tech used the "T" mark to set cams druing timing belt job. Very few service manager have enough knowledge of these engine to even know about the "T" mark. So his story rang true, as did all info he gave me.

This may by due to slight change in piston. The VVT has 10:1 as opposed to 9.6:1 compression of non.

I have not seen even unsupported or hearsay claims of damage on a non-VVT which is not to say they're not out there. I was just looking for a documented example.

 

[2001LC]

I have not seen even unsupported or hearsay claims of damage on a non-VVT which is not to say they're not out there. I was just looking for a documented example.

I have.

One being local Rising Sun member. He was selling a 2000 with blown engine due to timing belt. He told me the engine was frozen and would not turn over due to timing belt break. I asked if he'd scoped it to see interference damage, he said no. I explained there are other things that may interfere with being able to turn crank. He sold and I never heard outcome.

We've also seen claims in mud over the years of engines locked up or blown due to suspect timing belt break. These were cases where they did not come back and give final us out come in mud. If you search hard and long enough you'll find them!

That said, we've seen in mud, those that though engine blew. But found by installing a new belt all was fine, that did report back.

 

[97 AZ LC]

That said, we've seen in mud, those that though engine blew. But found by installing a new belt all was fine, that did report back.

It seems like I've seen at least a dozen of those non-interference events, and several at high speed/RPM. I'm still seeking a documented interference event - and if/when I find one I'll then manage the risk of a blown engine versus the risk of a tow because they're very different risks.

 

[2000_land_cruiser]

Here are pics of my two 100 series before I changed them Both had the original belt and had 220k and 240k on them. Take it with a grain of salt but it could be fine for another 50k but you never know ...

 

[wvrx]

Thanks for providing a visual frame of reference...I definitely think my belt is the one from 120k miles ago. But it seems that the outside surface cracks don’t mean a whole lot as the teeth on your belts posted look to be in decent shape.

If anything it’s the water pump that would cause more issues...I’ve done my fair share of reading and several people have mentioned snapped belts due to a seized water pump.

Is there a good way to inspect the pump without tearing it all apart?

 

[2001LC]

Water pump will leak 99 out of 100 times before taking out a belt. Which can be seen at weep hole. Bad bearings in idlers will also take out the belt as will a weak tensioner. The bearings can be heard, but extremely difficult to isolate sound. The tensioner can be pulled and inspected.

 

[abuck99]

The T belts are fiber reinforced adding tensile strength but the cracking is an indication of weakening of the composite rubber. When the belt breaks it can destroy covers, connectors and wires, or get jammed and create other unforseen damage. Why wait?

The parts cost of replacing the belt and related tensioner, tensioner pulley, idler and waterpump is stupid cheap - under $200. You can and should do some other things while your in there adding a little extra cost, but I dont get the reason for this debate discussion that its fine to put it off 20-50+ thousand miles- it’s not worth the jellyfish effect on the other components.

Either do it reasonably soon, or just wait and chance a failure: the belt, one of the idlers or waterpump seizes and leaves you stranded. Ive read of two broken belts this month from seized idlers or water pump.

 

[wvrx]

I have a tiny garage that the LC doesn’t fit in unless the tires are completely flat and roof rack is off, and even then I can’t close the door once it’s inside...plus all of my tools are in another state so I would be doing the job illegally parked in the back alley with basic hand tools (maybe justify buying a battery operated impact).

Looks to be more labor intensive than your average DIY in a day job, so I would like to have my resources (time and tools) ready before tackling it, and if the belt is in passable condition, I can focus on getting the rest of the rig baseline’d first.

 

[batcon]

Here are pics of my two 100 series before I changed them Both had the original belt and had 220k and 240k on them. Take it with a grain of salt but it could be fine for another 50k but you never know ...

View attachment 1863396

View attachment 1863397

This is exactly how my belt looked with 234,000 miles when I swapped it out.

 

[abuck99]

I have a tiny garage that the LC doesn’t fit in unless the tires are completely flat and roof rack is off, and even then I can’t close the door once it’s inside...plus all of my tools are in another state so I would be doing the job illegally parked in the back alley with basic hand tools (maybe justify buying a battery operated impact).

Looks to be more labor intensive than your average DIY in a day job, so I would like to have my resources (time and tools) ready before tackling it, and if the belt is in passable condition, I can focus on getting the rest of the rig baseline’d first.

Fair enough-having a usable work space and the right tools on hand makes a big difference. Fwiw if you’re not doing other maint at the same time it is easily a 1 day job.

I wouldnt bank on anyones opinion looking at a picture of the belt could objectively suggest it will last 5k or 50k. There have been several posts of belts here with high miles 150k + plus service intervals or original and others breaking belts in the same mile range. You are at 120k on the belt and 11~12years of service, and based on forum experience of belt failure you may have a little safety margin (Im surprised at the cracks at this age and miles though), but if you dont know if the waterpump, tensioner or the idlers was done at the same time then its more reason to do it sooner than later as those are more likely to cause issue before a belt failure. Another note; while its customary to also change waterpump, tensioner and pulleys at the 90k service, some people decline doing so. I found this to be the case on my truck. With out knowing for sure ( work order notes), you can just use your own best judgement as to the priority of getting this knocked out.

BTW, have you pulled the Toyota service history to confirm?