Early timing belt failure

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tmils470

10 Year
Joined
Feb 3, 2014
Threads
17
Messages
87
Location
Walnut Creek CA
1 Timing belt skipped a tooth and shows shedding at 66,000 miles after changing it.
Any ideas what to look for as the cause?
Tensioners?
Rails?
Are tensioners hydraulic or just spring loaded?
Work was done by an avid LC shop so I'm really surprised and disappointed with the failure.
Car is far from the LC shop so I'm getting it repaired by my local shop and want to know any causes to look for so this does not happen again.
166000 Miles on motor
Basically a soccer mom vacation rig usage. No mods.
First problem with this car. Always been super dependable with meticulous maintenance.
 
I heard from OverlandBound that there is Top Shop Auto in Layfatte (seems like they moved to Walnut Creek according to their website) where Michael (founder of OB) brings his 80 series in for everything. May be worth giving them a call if it's close enough.
 
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Check all t-belt components, but be sure there isn't another odd failure (like a cam seizing) that precipitated this failure.
 
I have seen very few (Actual) belt failures in the 30 plus years of wrenching, It is not uncommon for something to take out a TB at that mileage most belt could last over a 100k as long other components are in good shape. Timing belt will only skip if belt is really stretched or a collapsed tensioner (Hydraulic) or other components breaking up. My question to you is when they did the timing belt was every component replaced? What brand is the parts that were installed?
 
vipergrhd said:
I have seen very few (Actual) belt failures in the 30 plus years of wrenching, It is not uncommon for something to take out a TB at that mileage most belt could last over a 100k as long other components are in good shape. Timing belt will only skip if belt is really stretched or a collapsed tensioner (Hydraulic) or other components breaking up. My question to you is when they did the timing belt was every component replaced? What brand is the parts that were installed?
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I was told that all components were replaced, not just the timing belt. They were ASIN parts.
If the tensioners are hydraulic, could low oil pressure at start up cause this combined with a leaky tensioner that is not holding residual pressure after the car is sitting unused for a week?
The engine always made some noise at cold start that would go away within seconds. Could that have been the delay in the tensioners pressure build up causing a momentary rattling noise?
 
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SteveH said:
Check all t-belt components, but be sure there isn't another odd failure (like a cam seizing) that precipitated this failure.
Click to expand...
Thanks. Are there other components that fail that could cause this? Trying to figure out what to look for and what is most likely the cause.
The car was running so cam is not seized.
 
tmils470 said:
I was told that all components were replaced, not just the timing belt. They were ASIN parts.
If the tensioners are hydraulic, could low oil pressure at start up cause this combined with a leaky tensioner that is not holding residual pressure after the car is sitting unused for a week?
The engine always made some noise at cold start that would go away within seconds. Could that have been the delay in the tensioners pressure build up causing a momentary rattling noise?
Click to expand...
The tensioner is a sealed unit, you need to have a shop do a teardown and see why it failed so early. Noise on cold start up could be anything from bearing noise or even exhaust leak. If the job is still under warranty why not have it towed to the shop that did the work?
 
I contacted the original shop and they could not look at it until JUL 15. (5 weeks from start of problem)
I was going with rodent wiring problems as most likely so I brought it to a local trusted mechanic but not an LC shop.
We eliminated any electrical, rodent issues and found the failed timing belt. Still not completely torn down to discover possible contributing mechanical problems.
OG LC shop still not stepping up to take the job but are interested to find out what happened?!
 
newbielx470 said:
I heard from OverlandBound that there is Top Shop Auto in Layfatte (seems like they moved to Walnut Creek according to their website) where Michael (founder of OB) brings his 80 series in for everything. May be worth giving them a call if it's close enough.
Click to expand...
Thanks I'll check them out.
 
vipergrhd said:
The tensioner is a sealed unit, you need to have a shop do a teardown and see why it failed so early. Noise on cold start up could be anything from bearing noise or even exhaust leak. If the job is still under warranty why not have it towed to the shop that did the work?
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Is the tensioner normally changed when the TB is changed?
 
“Timing belt failures” are usually not the belt failing, but one of the other components in the system like an idler pulley, tensioner, or water pump. These items can add stress to the belt or flat out strip the teeth off if they seize.

The 2UZ has a belt, tensioner, two idler pulleys, and a water pump as part of the system. All should be replaced at the same time, but its common that shops or people dont.
 
Rhetoric said:
“Timing belt failures” are usually not the belt failing, but one of the other components in the system like an idler pulley, tensioner, or water pump. These items can add stress to the belt or flat out strip the teeth off if they seize.

The 2UZ has a belt, tensioner, two idler pulleys, and a water pump as part of the system. All should be replaced at the same time, but its common that shops or people dont.
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tmils470 said:
1 Timing belt skipped a tooth and shows shedding at 66,000 miles after changing it.
Any ideas what to look for as the cause?
Tensioners?
Rails?
Are tensioners hydraulic or just spring loaded?
Work was done by an avid LC shop so I'm really surprised and disappointed with the failure.
Car is far from the LC shop so I'm getting it repaired by my local shop and want to know any causes to look for so this does not happen again.
166000 Miles on motor
Basically a soccer mom vacation rig usage. No mods.
First problem with this car. Always been super dependable with meticulous maintenance.
Click to expand...



Thanks for all the responses.
Seems that it was a bad belt. Interesting thing about the belt is that it was Toyota Brand part MADE IN USA.
All parts are changed and hopefully I will get the full useful life out of this belt.
Really glad it did not bend a valve or have some other catastrophic event.
 
A "Toyota" belt? You said Aisin kit all components changed. Which Aisin kit T-belt, does not say Toyota on the belt..

Likely a bootleg Aisin kit.
 
A Toyota belt with “made in USA” on it seems incredibly suspect. I doubt even US made 2UZs ever had a USA made timing belt on them.

OP: if you installed a new belt without touching any other components I would watch it very carefully. Something else in your timing path could be shredding it.
 
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Rhetoric said:
A Toyota belt with “made in USA” on it seems incredibly suspect. I doubt even US made 2UZs ever had a USA made timing belt on them.

OP: if you installed a new belt without touching any other components I would watch it very carefully. Something else in your timing path could be shredding it.
Click to expand...
Yes we installed all new parts that come with the entire kit.
 
2001LC said:
A "Toyota" belt? You said Aisin kit all components changed. Which Aisin kit T-belt, does not say Toyota on the belt..

Likely a bootleg Aisin kit.
Click to expand...
I was told Asin kit
 
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